AGRICULTURE NOTES

Soil Fertility ll

(Inorganic Fertilizers)

Introduction

Plant nutrients occur in the soil in form of soluble substances.

 These substances are taken in by the plants in different quantities depending on their roles in
the plant tissues.

Essential Elements

These are nutrients needed by plants for various uses.

They are divided into two broad categories namely:

 > Macronutrients
 > micronutrients.

Macro-nutrients

 These are also referred to as major nutrients.

 They are required by the plant in large quantities.

They include;

 carbon,
 hydrogen,
 oxygen,
 nitrogen,
 phophorus,
 potassium,
 sulphur,
 calcium
 magnesium.

> Nitrogen, phosphorus and potassium are referred to as fertilizer elements,

> Calcium, magnesium and sulphur, are referred to as liming elements.

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Role of Macro nutrients in Plants

Nitrogen (N03,NH4“)

Sources

 Artificial fertilizers
 Organic matter
 Atmospheric fixation by lightning
 Nitrogen fixing bacteria.

Role of Nitrogen in Plants

 Vegetative growth
 Chlorophyll formation
 Build up of protoplasm.
 Improves leaf quality in leafy crops such as tea and cabbages

Deficiency Symptoms

 I Yellowing of the leaves/chlorosis.

 I Stunted growth.
 Premature ripening.
 Premature shedding of the leaves.
 Light seeds.

Effect of Excess Nitrogen

 Scorching of the leaves.

 Delayed maturity.

Loss of Nitrogen From the Soil:

 Soil erosion.
 Leaching.
 Volatilization.
 Crop removal.
 Used by microorganisms.

Phosphorus (H, P04, HPO"4 P105)

Sources:

 Organic manures
 Commercial fertilizers

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 Phosphate rocks

Role of Phosphorus

 Encourages fast growth of the roots.

 Improves the quality of the plant.
 Hastens maturity of the crops.
 Influences cell division.
 Stimulates nodule formation in legumes.

Deficiency symptoms

 Growth of the plant is slow.

 Maturity is delayed.
 Leaves become grey, purple in colour.
 Yield of grains, fruits and seed is lowered.

Loss of Phosphorus From the Soil

 Soil erosion.
 Leaching
 Crop removal
 Fixation by iron and aluminium oxide.

Potasium (K„, K20)

Sources;

 Crop residue and organic manures.

 Commercial fertilizers
 Potassium bearing minerals e.g. feldspar and mica.

Role of Potassium in Plants

 Increases plant vigour and disease resistance.

 Increases the size of grains and seeds.
 Reduces the ill-effects due to excess nitrogen.
 Prevents too rapid maturation due to phosphorus.

Deficiency Symptoms

 Plants have short joints and poor growth.

 Plants lodge before maturing.
 Leaves develop a burnt appearance on the margin.
 Leaves at the lower end of the plant become mottled, spotted or streaked.
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 In maize, grains and grasses firing starts at the tip of the leaf and proceeds from the edge
usually leaving the midrib green.

Loss of Potassium From the Soil

 Crop removal.
 Leaching.
 Soil erosion.
 Fixation in the soil.

Calcium (Ca2+)

Source:

 Crop residues and organic manures.

 Commercial fertilizers.
 weathering of soil minerals.
 Agricultural limes for example dolomite, limestone.

Role of Calcium in Plants

 Improves the vigour and stiffness of straw.

 Neutralizes the poisonous secretions of the plants.
 Helps in grain and seed formation.
 Improves the soil structure.
 Promotes bacterial activity in the soil.
 Corrects the soil acidity.

Deficiency symptoms

 Young leaves remain closed.

 There are light green bands along the margins of the leaves.
 Leaves in the terminal bud become hooked in appearance there is a die-back at the tip and
along the margins.

Loss of Calcium

 Crop removal
 Leaching
 Soil erosion

Magnesium (Mg2+)

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Sources:

 Crop residues and organic manures

 Commercial fertilizers
 Weathering of soil minerals.
 Agricultural limes.

Role of Magnesium in Plants

 Forms part of chlorophyll.

 Promotes the growth of the soil bacteria and enhances the nitrogen fixing power of the
legumes.
 Activates the production and transport of carbohydrates and proteins in the growing plant.

Deficiency symptoms

 Loss in green colour which starts from the bottom leaves and gradually moves upwards.
 The veins remain green.
 Leaves curve upwards along the margins.
 Stalks become weak and the plant develops long branched roots.
 The leaves become streaked.

Sulphur (S04 2' ,SO,)

Sources:

 Commercial fertilizers.
 Soil mineral containing sulphides
 Atmospheric sulphur from industries.
 Rain water

Role of Sulphur in Plants

 Formation and activation of coenzyme-A.

 Sulphur is a constituent of amino acids.
 Influence plant physiological processes.

Deficiency Symptoms

 Small plants/stunted growth.

 Poor nodulation in legumes.
 Light green to yellowish leaves/ chlorosis.
 Delayed maturity.

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Micro-nutrients

 Also referred to as trace or minor nutrients.

 They are required in small quantities/traces.
 They are essential for proper growth and development of plants.

They include;

 Iron,
 Manganese,
 Copper
 Boron,
 Molybdenum
 Chlorine.

Role of Micronutrients and Their Deficiency Symptoms

 Copper

> Role in oxidation-reduction reactions.

> Respiration and utilization of iron

> Deficiency symptoms-yellowing of young leaves.

 Iron

> Synthesis of proteins.

> Takes part in oxidation-reduction reactions.

> Deficiency symptoms - leaf chlorosis

 Molybdenum

> Nitrogen transformation in plants.

> Metabolization of nitrates to amino acids and proteins

> Deficiency symptoms -leaf curl and scathing.

 Manganese - Same as molybdenum.

 Zinc

> Formation of growth hormone.

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> Reproduction process

> Deficiency symptoms - white bud formation.

 Boron

> Absorption of water.

> Translocation of sugar

Inorganic Fertilizers

 These are chemically produced substances added to the soil to improve fertility Classification
According to:
 Nutrients contained

> Straight - contain only one macronutrient.

> Compound fertilizers - contain more than one macronutrient

 Time of application

Some applied when planting.

Top dressing after crop emergence

 Effects on the soil pH.

> Acidic fertilizers.

> Neutral fertilizers.

> Basic fertilizers.

Properties and Identification of Fertilizers

Nitrogenous Fertilizers

Characteristics

 Highly soluble in water.

 Highly mobile in the soil hence it is applied as a top dress.
 Easily leached because of the high solubility hence does not have residual effect on the soil.
 Has scorching effect on young crops during wet seasons.
 Easy to volatilize during hot season.

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 They have a tendency to cake under moist conditions.

 They are hygroscopic hence should be stored in dry conditions.

Examples:

 Sulphate of Ammonia (NH4) 2 SO4-

Physical appearance:

> white crystals,

> Has acidic effect,

> Contains 20% N.

 Ammonium Sulphate Nitrate [(NH4),SO4+ NH4 NO;]

> Colour: granules which appear yellow orange,

> less acidic,

> contains 26% N.

 Calcium Ammonium Nitrate (CAN)

> Colour: greyish granules,

> neutral in nature,

> contains 21 % N.

 Urea

> Colour: small whitish granules

> Easily leached or volatilized,

> contains 45- 46%N.

Phosphate Fertilizers

 Has low solubility and immobile.

 Non-scorching.
 Has a high residual effect hence benefit the next season's crop.
 Easy to store because they are not hygroscopic.

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Examples;

 Single super-phosphate

> Appearance: whitish, creamy white granules,

> contains 20-21 % P,O5

 Double super-phosphate

> Appearance: dark greyish granules,

> Contains 40-42% P205

 Triple super-phosphate

> Appearance: small greyish granules,

> Contain 44-48% P205

Potassic Fertilizers

Characteristics:

 Has moderate scorching effect.

 Moderately soluble in water.
 Most Kenyan soils have sufficient potassium.

Examples;

 Muriate of Potash (KCI)

> Contain 60 - 62% K10

> Slightly hygroscopic.

> Appearance amorphous white.

 Sulphate of Potash (50% K10)

Compound or Mixed Fertilizers

 These are fertilizers which supply 2 or more of the macronutrients.

Examples;

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 Mono ammonium phosphate.

 Di-ammonium phosphate
 20:20:20, 23:23:23

Advantages of application of compound fertilizers

 Saves time and money.

 Mixture gives improved storage properties and better handling.

Disadvantages of compound fertilizers application

 Expensive.
 Wasteful.
 Mixing may not be thorough.
 Incompatibility of the individual fertilizers.

Methods of fertilizer application

 Broadcasting - random scattering of the fertilizers on the ground.

 Placement method - application of fertilizers in the planting holes.
 Side dressing - fertilizer is placed at the side of the plant within the root zone, in bands or
spot-rings.
 Foliar spraying - specially formulated fertilizer solution applied on the foliage in spray form.
 Drip method - applied through irrigation water.

Determination of Fertilizer Rates

Contents of fertilizers are expressed as fertilizer grade or fertilizer analysis.

 Fertilizer grade indicate the guaranteed minimum of the active ingredients (N, P205, K 20) in
the mixture.
 It is expressed as a percentage on a weight to weight basis or percentage by weigh

Example 10:20:o means for every 10kg of the mixture there are 10kg of nitrogen, 20kg of P10 5
and okg of K20.

Example

A farmer was asked to apply fertilizers as follows:

 60 kg/ha nitrogen (top dressing)

 60 kg/ha P205 (in planting hole).
 60 kg/ha K20. How much sulphate of ammonia (20%) would be required per hectare? How
much double super-phosphate (40%) P2O5would be required per hectare? How much muriate of
potash (50% K20) would be required per hectare?

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Answer/Solution

 Sulphate of ammonia (SA) which gives 60kg/ha N

60/20 x 100 = 300 kg SA

 Double super phosphate (40% P2O5)which gives 60kg/ha P205

60/12 x 100 = 150 kg DSP

 Muriate of potash (60% K20) which gives 60kg/hK2O

=60/60 x 100 = 100 kg muriate of potash

Example

A farmer was asked to apply fertilizers as follows:

 200kg/ha of DSP (40% P205

 150kg/ha of muriate of potash (60% K20)
 150kg/ha of sulphate of ammonia (20% N)

How much P205 did the farmer apply per acre?

How much K20 did the farmer apply per hectare?

How much N did the farmer apply per hectare?

Solution/Answer

 P205 applied per hectare from 200kg of DSP 40/100 x 200 = 80 kg/ha P205
 K205 applied per hectare from 150 kg of muriate of potash = 60/100 x 150 = 90 kg/ha K20
 N applied per hectare from 150 kg/ha sulphate of ammonia 20/100 x 150: 30 kg/ha N

Soil Sampling

 Refers to obtaining of small quantity of soil that is representative in all aspects of the entire
farm.

Soil Sampling Procedures

 Clear the vegetation over the site.

 Dig out soil at depths of 15-25cm.
 Place the dug out soil in a clean container.
 Mix thoroughly the soil in the container.

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 Take a sample and send it to National Agricultural Laboratory for analysis.

 The container carrying the sample should be properly labeled as follows:

> Name of the farmer,

> Location,

> District

> Address of the farmer.

Sites to Avoid

 Dead furrows, ditches.

 Swamps
 Near manure heaps.
 Recently fertilized fields
 Ant hills.
 Under big trees.
 Near fence lines or foot paths.
 Do not put them in containers which are contaminated with fertilizers or other chemical
containers.

Methods Of Soil Sampling:

 Zigzag method
 Traverse method

Soil Testing

 Soil testing is the analyzing of the soil sample to determine certain qualities of the soil.

Importance of Soil testing:

 To determine the value of the soil hence determine the crop to grow.
 To determine the nutrient content hence find out the type of fertilizer to apply.
 To determine whether it is necessary to modify the soil pH for a crop.

How Soil pH affects Crop Production

 Influences the physical and chemical properties of the soil.

 Affects the availability of nutrients.
 Influences the incidences of soil borne diseases.
 Determine the type of crop to be grown at a given area.

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Methods of pH Testing

 Universal indicator solution

 pH meter

> Know the course of action to be taken in the event of a disease and maintenance of good
health.

> Know the prevalent diseases.

> Calculate the cost of treatment.

 Marketing Records show commodities sold, quantities and value of all the sales.

Labour Records - show labour utilization and labour costs.

Crop production ii

(Planting)

 Planting is the placement of the planting material in the soil for the purpose of regeneration in
order to produce more of the plant species.

Types of planting materials

Seeds

 Seeds are produced by flowering after pollination and fertilization. They contain the part of the
plant that germinates and subsequently grows in to new plants. Advantages of using seeds as
planting materials.
 Seeds are easily treated against soil borne pests and diseases.
 They are not bulky therefore storage is easy.
 They are easy to handle during planting making operation easy.
 When planting seeds, it is easy to use machines like seed planters and drillers.
 It is easy to apply manures and fertilizers together with seeds during planting.
 Fertilizers and manures application can be easily mechanized.
 It is possible to develop new crop varieties due to cross pollination.

Disadvantages of using seeds as planting materials.

 Some seeds have long dormancy and they may need special treatment in order to germinate.
 Plants raised from seeds have variations from the mother plant due to cross pollination,
 This may introduce undesirable characteristics.
 Soil borne pests may damage seeds if left for sometime in the soil before rain falls.
 Some seeds may lose viability if stored for a long time. This leads to gaps in the farm.

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1. Vegetative materials.

 These are plant parts which have the ability to produce roots, they grow and develop in to new
plants.
 Plant parts such as leaves, roots or stems can be used for planting as long as they are capable
of rooting. Advantages of using vegetative materials for planting.
 Crops originating from vegetative materials matures fasterthan those from seeds.
 The crops shows uniformity in such qualities as disease resistance, seed size, colour, keeping
or storing quality and chemical composition.
 It is possible to produce many varieties of compatible crops on the same root stock.
 Use of the vegetative materials is easier and faster, especially where seeds show prolonged
dormancy.
 The resulting plant has desired shape and size for ease of harvesting and spraying.
 It facilitates the propagation of crops which are seedless or those that produce seeds which are
not viable or have a long dormancy period.
 Such crops include sugar-cane, bananas, Napier grass and others.

Disadvantages.

 Vegetative propagation does not result in new crop varieties.

 Keeping the materials free of diseases is difficult.
 Materials cannot be stored for long.
 The materials are bulky and there fore difficult to store and transport.

Plant parts used for vegetative propagation.

i) Bulbils.

 These are tiny sisal plants produced in the inflorescence almost at the end of the plant growth
cycle.
 They resemble the mother plant except that they are smaller in size.
 They are produced by the branches of the sisal pole.
 When manure they mature they develop rudimentary roots and fall off to the ground just
below the pole.
 They are the collected and raised in the nurseries before they are transplanted t\o the main
field.
 One sisal pole may produce as many as 3,000 bulbils. They are usually 10cm long. They make
good planting materials and are better than sucke

ii) Splits

 These are plantlets divided from the existing mother plant with complete with complete leaves
and rooting system.
 They are used to propagate most pasture grasses and pyrethrum.
 Pyrethrum splits are raised first in nursery and then transplanted to the field.

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iii) Crowns and slips

 These are materials used to propagate pineapples

 Crowns are born on top of the fruits and are broken off and prepared for planting.
 They are more preferred to suckers because they give uniform growth and take two years to
reach maturity.
 Slips are borne to the base of the pineapple fruits.
 They are cut and prepared for plantings.
 Their growth rate is faster than for crowns giving average uniformity.
 They take 22 months from planting to maturity.
 Crowns and slips are planted in the nurseries first before transplanting to the main seed bed.

iv) Suckers

 These are small plants that grow from the base of the main stem.
 They have adventitious roots which grow quickly when planted to form a new plant.
 They are used to propagate bananas, sisal, and pineapples.
 When planted, suckers give uneven growth leading to maturity at different times.
 They should be planted when they are young.

v) Tubers

 These are underground food storage organs which are short and thick.
 They are used as vegetative propagation materials because they sprout and produce roots for
growth.
 There are mainly two types of tubers, the stem and root tubers.
 Root tubers develop from the thickening of the adventitious roots.
 Root tubers are not commonly used for propagation since they produce weak stems.
 A good example of a root tuber is the sweet potato.
 On the other hand stem tubers have some auxiliary buds which are sometimes referred to as
‘eyes’.
 These eyes sprout to produce stems which grow into plants. Stem tubers are therefore swollen
stems with scales leaves.
 A good example of a stem tuber is Irish potato.

vi) Vines.

 These are soft wood cuttings which produce roots easily upon planting to give rise to new
plants.
 They are cut from the mother plants and planted directly into the field.
 Soft wood cuttings (vines) are taken from rapidly growing shoots.
 The soft upper parts of the shoots are preferred.
 When preparing the cuttings, some leaves and nodes are included.
 Roots are produced from the nodes.

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vii) Cuttings and setts

 Cuttings are portion of plants parts which are cut and then planted.
 They may be from stems, roots or leaves.
 A stem cutting must have a bud which develops into shoot.
 The root cutting must have an eye. Cutting must have an eye.
 Cuttings must produce leaves as soon as possible so that they can start making their own food.
 Sometimes cuttings are induced to produce roots by use of rooting hormones.
 Once the cuttings have developed roots, they give rise to new plants.
 In some crops, the cuttings are big enough to be planted directly to the main seedbed whereas
there are some plants whose cuttings are first raised in special nurseries before they are
transplanted to the seedbed.
 The cuttings of Napier grass and sugar-cane are planted directly on the seedbed but those of
tea; have to be raised in special nursery before they are transferred to the seed bed.
 Examples of crops which are propagated by use of stem cuttings include: tea, cassava, and
sugar-cane and Napier grass.
 The stem cuttings used to propagate sugar-cane are known as ‘setts’. Setts are stem cuttings
which have 3-5 nodes are usually 30-45 cm long.

Factors affecting rooting of cuttings.

 Temperature: for the cuttings to produce roots warm temperatures are required around the
root zone while cool temperatures are important for the aerial part of the cuttings. For most
species optimum day and light temperatures for rooting are 22 -27°c and 15-21° c respectively.

a) Relative humidity: Proper rooting of cuttings requires high humidity which lower the
transpiration rate. it also increases and maintains leaf turgidity all the time. As such, cuttings
should be rooted in green houses or under shady conditions, where relative humidity can be
regulated. Sometimes the propagation area can be sprayed with water to keep it moist.

b) Light intensity: soft wood cuttings need high intensity light to produce roots. This is because
light promotes the production of roots since it affects the rate of photosynthesis. Hard wood
cuttings do well in dark conditions since they have high amount of stored carbohydrates and
therefore rooting is excellent in darkness.

c) Oxygen supply: plentiful supply of oxygen is required for root formation. The rooting
medium used must therefore be capable of allowing proper aeration.

d) Chemical treatment: these rooting hormones which promote the production of roots in
cuttings. The common ones include [AA (indoleacetic acid).

e) Leaf area: Soft woods cuttings require a lot of leaves for photosynthesis while hardwood
cuttings will produce roots better without leaves.

Selection of planting materials

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When selecting materials for planting the following factors must be considered:

 Suitability to the ecological conditions — the selected planting materials should be well
adapted to the soil conditions, temperatures and amount of rainfall in the area. There are many
varieties of maize, for example, which are suitable to different ecological conditions. Hybrid
622f or example is mainly for the high altitudes areas of Kenya 513 for the medium altitudes and
the Katumani composites for the low rainfall areas while the coast composites are suitable for the
coastal conditions each variety will grow well and produce high yields if grown under the correct
conditions
 Purity of the materials - planting materials should be pure and not mixed with other off types
the percentage purity of planting materials will affect the seed while higher seeds rates are used
for impure seeds.
 Germination percentage - This is a measure of the germination potential of seeds it is
expressed as a percentage for example a germination percentage of 80 means that for every 10
seeds planted 80 of them are expected to germinate. Germination percentage helps to determine
the seed rates of crops lower seed rates are used for crops with higher germination percentage
while higher seed rates are used for those with lower germination percentage.
 Certified seeds - These are seeds which have been tested and proven to have 100 germination
potential and free from diseases and pests they give high yields after the first planting but the
subsequent yields decline if replaced therefore in this case it is always advisable to buy new
seeds which are certified every time planting is done In Kenya certified seeds are produced by
the Kenya seed company(KSC) and distributed by Kenya Farmers Association (KFA) and other
agents.

Preparation of planting materials.

After the planting materials are selected they are prepared in different ways before they are
planted. Some of the methods used to prepare planting materials include the following:

(a)Breaking the seed dormancy.

Some seeds undergo a dormancy period between maturity and the time they sprout. The
dormancy period is the stage whereby a seed cannot germinate, the stage of inhibited growth of
seed. it should be broken before the seed is planted.

Methods of breaking seed dormancy.

The following methods are used to break seed dormancy:

(i) Mechanical method: This is a method which aims at scratching the seed coat to make it
permeable to water. Scarification is done by rubbing small sized seeds against hard surface such
as sand paper, while filling or nicking the seed coat with a knife is done to large sized seeds such
as croton seeds.

(ii) Heat treatment: this involves the use of hot water or burning the seeds lightly. It softens the
seed coat making it permeable to water and thus is able to germinate. The seeds are soaked in hot

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water about 80’c for 3-4 minutes after which the water is allowed to drain off. Example of seeds
treated in this way include: leucean 7a2 + 32 = 22 calliadra and acacia.

Light burning also serves the same purpose as hot watertreatment. In this case trash is spread
over the seeds which are already covered with a thin layer of soil. The trash is burned, after
which the seeds are retrieved and planted. Examples include acacia and wattle tree seeds.
Overheating should be avoided as this will cook the seeds.

(iii)Chemical treatment: seeds are dipped in specific chemicals such as concentrated sulphuric
acid, for two minutes and then removed. The chemical wears off the seed coat making it
permeable to water. Care should be taken not to leave the seeds in the chemicals for too long as
this will kill the embryo. Cotton seeds are normally treated with chemicals to remove the lint or
fibres.

iv) Soaking in water: seeds are soaked in water for a period of between 24 — 48 hours until
they swell. They are then removed and planted immediately. The seeds treated thus germinate
very fast. Pre-germinated seeds are used when raising rice in the nurseries.

b) Seed dressing

This is the coating of seeds with fungicides or an insecticide or a combination of the two
chemicals. This is particularly common with cereals, sugar-cane and legumes. The chemicals
protect the seedlings from soil-borne diseases and pests. Certified seeds which are sold by seed
merchants in Kenya have been dressed with these chemicals. Farmers can also buy the chemicals
and dress their own seeds.

c) Seed inoculation

In areas where soils are deficient in nitrogen, legumes such as beans, clovers and peas should be
coated with an inoculant. An innoculant is a preparation which contains the right strain of
Rhizobium depending on the type of legume and encourages nodulation, hence nitrogen fixation.
Below is a table showing different legume crops and their right strain of Rhizobium.

Crop inoculation group

 Lucerne
 Clover
 Pea
 Bean
 Lupin
 soyabean

Rhizobium Species

 R.melioti
 R.trifoli

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 R.leguminosarum
 R.phaseoli
 R.lupini
 R.japonicum

When handling inoculated seeds, care should be taken to prevent them from coming in contact
with chemicals. This means that inoculated seeds should not be dressed with chemicals as these
will kill the bacterium. They should also be planted when the soil is moist to avoid dehydration
which kills the bacterium.

d) Chitting

This practice is also referred to as sprouting. The selected seed potatoes ‘setts’ which are used as
planting materials are sprouted before planting to break their dormancy. The setts of about 3-6
cm in diameter are arranged in layers of 2 or 3 tubers deep in a partially darkened room. The
setts should be arranged with the rose» end facing upwards and the heel-end downwards.
Diffused light encourages the production of short, green and healthy sprouts.

If Chitting is done in complete darkness, long, pale thin sprouts develop which break easily
during planting. During Chitting potato aphids and tuber months should be controlled by dusting
or spraying the sett with dimethoate.

Sometimes a chemical known as Rendite is used to break dormancy, thus inducing sprouting.
Chitting is done mainly to make sure that growth commences immediately the seed is planted so
as to make maximum use of rains for high yields.

Time of planting

The timing of planting or sowing is influenced by the type of crop to be planted and the
environmental conditions of the area.

Factors to consider in timing planting.

 The rainfall pattern/moisture condition of the soil.

 Type of crop to be planted.
 Soil type.
 Market demand.
 Prevalence of pests and diseases.
 Weed control.
 Timely planting is necessary and should be done at the onset of rains. in some areas where
rainfall is scare dry planting is recommended.

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Advantages of timely planting.

 Crops make maximum use of rainfall and suitable soil temperature, leading to vigorous
growth.
 Crops usually escape serious pests and diseases attack.
 Crops benefit from nitrogen flush which is available at the beginning of the rain.
 For horticultural crops, proper timing ensures that the produce is marketed when prices are
high.
 Crops establish earlier than the weeds, hence smothering them.

Methods of planting.

There are two main methods of planting :-

 Broadcasting.
 Row planting.

Broadcasting.

This method involves scattering the seeds allover the field in a random manner. It is commonly
adapted for light tiny seeds such as those of pasture grasses.

It is easier, quicker and cheaper than row planting. However, it uses more seeds than row
planting and the seeds are spread unevenly leading to crowding of plants in some places.

This results in poor performance due to competition. Broadcasting gives a good ground cover,
but weeding cannot be mechanized. For good results, the seedbed should be weed-free, firm and
have a fine tilth.

Row planting.

The seeds or other planting materials are placed in holes, drills or furrows in rows. The distance
between one row to the other and from one hole to the otheris known.

In Kenya, both large and small — scale farmers practice row planting. It is practiced when
planting many types of crops, especially perennial, annual and root crops.

Advantages of row planting.

 Machines can be used easily between the rows.

 It is easy to establish the correct plant population.
 Lower seed rate is used than if broadcasting is adopted.
 It is easy to carry out cultural practices such as weeding, spraying and harvesting.

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 AGRICULTURE NOTES

Disadvantages of row planting.

 It does not provide an ample foliage cover. Thus the soil is liable to being eroded by wind and
water.
 It is more expensive than broadcasting because of consuming a lot of labour and time.
 It requires some skill in measuringthe distances between and within the rows.

Seeds can also be planted by dibbling where the planting holes are dug by use of pangas or
jembe, or by a dibbling stick (dibbler). Most of the dibbling is done randomly although rows can
also be used when using a planting line.

Random dibbling is not popular in commercial farming due to low levels of production. It is only
common among conservative farmers in planting of legumes such as beans, pigeon peas and cow
peas.

Over-sowing.

This is the introduction of a pasture legume such as desmodium in an existing grass pasture.
Some form of growth suppression of existing grass such as burning, slashing or hard grazing plus
slight soil disturbance is recommended before over sowing. A heavy dose of super phosphate,
preferably single supers at a rate of 200- 400 kg/ha is applied.

The grass must be kept short until the legume is fully established. Regardless of the method of
establishment, the pastures and fodder stands should be ready for light grazing 4-5 months after
planting if rainfall and soil fertility are not limiting.

Under-sowing.

This refers to the establishment of pasture under a cover crop, usually maize. Maize is planted as
recommended and weeded 2-3 weeks after the onset of rains. Pasture seeds are then broadcasted
with half the recommended basal fertilizer.

No further weeding should be done and maize should be harvested early to expose the young
pasture seedlings to sunlight. The benefits of under sowing include facilitating more intensive
land utilization and encouraging an early establishment of pastures.

Fodder crops and vegetetively propagated pasture species may also be under sown as long as
rainfall is adequate for their establishment. Timing is not very crucial in this case and planting
can be done as late as 6-8 weeks after the onset of rains.

Plant population

This refers to the ideal number of plants that can be comfortably accommodated in any given
area, without overcrowding or too few to waste space.

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 AGRICULTURE NOTES

Agricultural research has arrived at the optimum number of various crop plants to be
recommended to farmers. Plant population is determined by dividing the planting area by
spacing of the crop. This may be simplified thus:

Plant population = Area of land divided by Pacing of crop

Example

Given that maize is planted at a spacing of 75 x 25 cm, calculate the plant population in a plot of
land measuring 4 x 3 m.

Working

Area of land = Plant population divided by Pacing of crop

Area of land = 400 cm x 300 cm

Spacing of maize = 75 cm x 25 cm

Therefore, plant population = 400 cm x 300 cm

75 cm x 25 cm

= 64 plants.

Spacing

It is the distance of plants between and within the rows. Correct spacing for each crop has been
established as shown in table below.

Crop

Maize (Kitale)

hybrids

spacing

75-90 cm x 23—30 cm

Crop

Coffee

(Arabica) tall varieties

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 AGRICULTURE NOTES

Spacing

2.75 cm v 2.75 m

Crop

Tea

spacing

1.5 m by 0.75 m

Crop

Beans (erect type)

spacing

45 -60 m by 25 cm

Crop

Bananas

spacing

3.6 — 6.0 m by 3.6 — 4.5 m

Crop

Coconut

spacing

9mx9m

Crop

Tomatoes (Money maker)

spacing

100 x 50 cm

Crop

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 AGRICULTURE NOTES

kales

spacing

60 x 60 cm

Spacing determines plant population and the main aim of correct spacing is to obtain maximum
number of plants per unit area which will make maximum use of environmental factors.

Wider spacing leads to a reduced plant population which means lower yields, whereas closer
spacing could lead to overcrowding of plants and competition for nutrients and other resources
would occur. Correctly spaced crops produce yield of high quality that are acceptable in the
market.

Spacing is determined by the following factors:

 The type of machinery to be used.

The space between the rows should allow free passage of the machinery which can be used in the
field. For example, the spacing between rows of coffee is supposed to allow movement of tractor
drawn implements.

 Soil fertility

A fertile soil can support high plant population. Therefore closer spacing is possible.

 The size of plant

Tall crop varieties require wider spacing while short varieties require closer spacing, for
example, Kitale hybrid maize is widely spaced than Katumani maize.

 Moisture availability.

Areas with higher rainfall are capable of supporting a large number of plants hence closer
spacing than areas of low rainfall.

 Use of crop.

Crop grown for the supply of forage or silage material is planted at a closer spacing than for
grain production.

 Pest and diseases control.

When crops are properly spaced, pests might find it difficult to move from one place to the other,
for example, aphids in groundnuts.

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 AGRICULTURE NOTES

 Growth habit.

Spreading and tillering crop varieties require wider spacing than erect type.

Seed rate.

Seed rate is the amount of seeds to be planted in a given unit area governed by ultimate crop
stand which is desired.

The objective of correct spacing of crop is to obtain the maximum yields from a unit area
without sacrificing quality. Most crops are seeded at lighter rates under drier conditions than
under wet or irrigated conditions.

Seeds with low germination percentage are planted at higher rates than those which have about
100% germination percentage. There is an optimal seed rate for various crops.

For example, the seed rate for maize is 22 kg per hectare, wheat is 110 kg per hectare and cotton
is between 17 to 45 kg per hectare.

Factors to consider in choosing seed rates.

 Seed purity.

When planting seed which is pure or with a high germination percentage, less seed is required.
On the contrary, more seeds are required when using impure or mixed seeds.

 Germination percentage.

Less seed is used when its germination percentage is higher. Seed of lower germination
percentage is required in large amounts.

 Spacing.

At closer spacing, more seeds are used than in a wider spacing.

 Number of seeds per hole.

When two or more seeds are planted per hole, higher seed rate is required than when only one
seed is planted per hole.

 The purpose of the crop.

A crop to be used for silage making is spaced more closely than one meant for grain production.
This would require use of more seeds. Maize to be used for silage making, for example, requires
more seeds than that meant for production of grain.

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 AGRICULTURE NOTES

Depth of planting.

This is the distance from the soil surface to where the seed is placed. The correct depth of
planting is determined by:

 Soil type: seeds Will emerge from grater depths in sandy soil that are lighter than in clay soils.
 Soil moisture content: it is recommended that one plants deep in dry soils in order to place
the seeds in a zone with moist soil.
 Size of the seed: Larger seeds are planted deeper in the soil because they have enough food
reserves to make them shoot and emerge through the soil to the surface.
 Type of germination: seeds with epigeal type of germination (carry cotyledons above the soil
surface) such as beans, should be planted shallowerthan those with hypogeal type of germination
(leave cotyledons under the soil) such as maize.

Suggested Activities.

1.Learners to carry out planting using broadcasting method and planting rows.

2.Learners to identify different vegetative propagation materials displayed by the teacher.

3.Learners to determine the correct plant population for a given area by mathematical
calculations.

4.Learners to collect samples of different tree seeds and prepare them for planting by various
methods of breaking seed dormancy.

5.Learners to determine the germination percentage of different samples of cereals and legume
seeds.

Crop Production Ill

(Nursery Practices)

Introduction

 Planting materials are either planted directly in a seedbed or indirectly through a nursery bed.
 A seedbed is a piece of land which could be small or large and prepared to receive planting
materials.
 A nursery bed on the other hand is a small plot of land specially prepared for raising seedlings
or planting materials before transplanting.
 It is usually 1m wide and any convenient length depending on the quantity of seedlings to be
raised.
 A seedling bed is a special type of nursery bed used for raising seedlings pricked out from the
nursery bed due to overcrowding before they are ready for transplanting.
 Pricking out refers to the removal of seedlings from a nursery bed to a seedling bed.

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 AGRICULTURE NOTES

 Nursery practices refer to all the activities carried out throughout a nursery life to raise
seedlings.

Importance of Nursery Bed in Crop Production

 To facilitate the production of many seedlings in a small area.

 It is easy to carry out management practices in a nursery than in the seedbed.
 It facilitates the planting of small seeds which develop into strong seedlings that are easily
transplanted.
 It ensures transplanting of only healthy and vigorous growing seedlings.
 It reduces the period taken by the crop in the field.
 Excess seedlings from the nursery may be sold to earn income.

Selection of a Nursery Site

Factors to consider;

 Nearness to the water source.

 Type of soil.-should be well drained, deep and fertile, preferably loam soil.
 Topography.-it should be situated on a gentle slope to prevent flooding and erosion through
surface run-off.
 Previous cropping.-to avoid build up of pests and diseases associated with particular plant
families, consider the preceding crops.
 Security.-select a site that is protected from theft and destruction by animals.
 Protection against strong winds and heat of the sun.-select a sheltered place. i.e. to avoid
excessive evapotranspiration and uprooting seedlings.

Types of Nurseries

Categories of nurseries:

 Vegetable Nursery:

> They are used for raising the seedlings of vegetable crops.

> Tomatoes, cabbages, kale, onions, brinials and peppers.

 Vegetable Propagation Nurseries:

> They are used for inducing root production in cuttings before they are transplanted,

> The cuttings can be planted directly in the soil and hence called bare root nurseries.

> Or planted into containers such as pots, polythene bags and others, hence called containerized
nurseries.

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 AGRICULTURE NOTES

 Tree Nurseries:

> These are used for raising tree seedlings.

> The seedlings can be raised in bare root nurseries or in containerized nurseries.

Nursery Management Practices:

 These are the practices carried out in the nursery while the planting materials are growing.

They include:

 Mulching; —light mulch should be applied on thenursery bed.lt be should be removed on the
4 day
 Weed control.
 Shading.
 Pricking out.
 Pests and disease control.
 Hardening off
 Watering.

Preparation of vegetative materials for planting:

 Cuttings -These are plant parts such as stems, leaves and roots induced to produce roots and
used as planting materials.
 Grafting -

> It is the practice of uniting two separate woody stems.

> The part bearing the roots is referred to as root stock while the part which is grafted onto the
root stock is known as scion.

> The scion has buds which develop into the future plant.

> The ability of the root stock and the scion to form a successful union is termed as
compatibility.

Methods of Grafting

 Whip or tongue grafting:

> In this case the diameter of the rootstock and the scion are the same.

> It is carried out when the diameter of the scion and the rootstock is ‘pencil’ thick.

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 AGRICULTURE NOTES

 Side grafting:

In this case the diameter of the rootstock is bigger than that of the scion.

Other types of grafting include ;

 Approach rafting,
 Notch grafiing
 Bark grafting.

Budding:

 It is the practice of uniting a vegetative bud to a seedling of another plant.

 The scion has only one bud and some bark with or without wood.
 The bud is inserted in a slit made on the bark of the stock.
 It is held tightly on the stock by tying with a budding tape until it produces a shoot.

Methods of Budding:

 T-budding Top
 budding Patch
 budding.

Importance of Budding and Grafting:

 Plants with desirable root characteristics but with undesirable products may be used to produce
desirable products for example lemon-orange graft.
 They facilitate the changing of the top of the tree from being undesirable to desirable
 They make it possible to grow more than one type of fruit or flower on the same plant.
 They help to propagate clones that cannot be propagated in any other way.
 They help to shorten the maturity period.

Layering

 It is the process by which a part of a plant is induced to produce roots while still attached to
the mother plant.
 Once the roots have been produced, the stem is then cut off and planted.

Types of layering;

 Marcotting or aerial layering.

 Tip layering.
 Trench layering.
 Compound or serpentine.

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 AGRICULTURE NOTES

Tissue Culture for Crop Propagation

 Tissue culture is a biotechnology used in cloning vegetatively propagated plants.

 It is based on the ability of plant tissue (or cells) to regenerate other parts of the plant.
 The tissues are derived from shoot tips where cells are undergoing rapid cell division and are
not differentiated.
 The cells are then provided with the right conditions which enable them to multiply and
develop roots.

The Right Conditions for tissue culture:

 Culture medium.
 Correct temperature.
 Correct light intensity and
 Correct relative humidity.

Importance of Tissue Culture in Crop Propagation

 It is used to recover and establish pathogen-free plants especially in the control of viral
diseases.
 It is used in mass production of plantlets or propagules.
 It is fast and requires less space than the cultural methods of using cutting which requires a
bigger space.

Transplanting Seedlings

 Transplanting of vegetable and tree seedlings are generally the same.

 Generally, vegetable seedlings are ready for transplanting when they are one month old or
have 4 -6 leaves or are about 10-15cm in height.
 Before transplanting, the nursery bed is adequately watered 3 - 4 hours before lifting the
seedlings.
 This ensures the seedlings are lifted easily with a ball of earth around the roots to minimize
root damage.
 Tree seedlings take a little longer to reach transplanting age compared to vegetable crop
seedlings.
 The roots are trimmed before lifting the seedlings.
 Transplanting should be done at the onset of the long rains to give the young trees a good start.
 After transplanting the young trees should be protected from damage by animals for a period
of about one year.

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Crop production IV (Field Practices I)

Introduction

 Field practices are activities carried out on the field to facilitate proper growth and maximum
yield of the various crops grown.

They include the following:

 Crop Rotation
 Mulching
 Routing field practices
 Crop protection
 Harvesting

Crop Rotation

 This is the growing of different types on the same piece of land in different seasons, in an
orderly sequence.

Importance of Crop Rotation

 Maximizes use of nutrients and moisture.

 Breaks the life cycle of pests and disease agents.
 Maintains good soil structure.
 Reduces soil erosion due to adequate soil cover.
 Controls weeds that are specific to certain crops e.g. striga on cereals
 Improves soil fertility when legumes are included in crop rotation.

Factors Influencing Rotational Programme

 Growth habits and nutrient requirements.

 Liability to soil erosion.
 Crops attacked by the same pests and diseases should not follow one another in the
programme.
 Availability of capital and market for example beans or peas in legumes.

Mulching

 This is the placement of materials such as banana leaves or polythene sheets on the ground
next to the growing crop.
 These materials should not come into contact with the base of the crop as they may encourage
pest attack.

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 AGRICULTURE NOTES

importance of Mulching

 Reduction of evaporation rate.

 Smothers weeds.
 Moderation of soil temperature.
 Reduction of speed of run offs.

Types of Mulching Materials

 Organic mulching materials such as;

> Sawdust, wood shavings, coffee pulps, rice husks,

> Dry grass, banana leaves, dry maize stalk, napier grass.

 inorganic or synthetic materials commonly used are either black or transparent polythene
sheets.

Advantages of Mulching

 Prevents water evaporation thus maintaining moisture in the soil for crop use.
 Acts as an insulator thus modifying the soil temperature.
 It helps to control soil erosion.
 It controls weeds by suppressing them.
 After decomposition organic mulch add nutrients to the soil thus improving its fertility.
 Humus produced after the decomposition of organic mulch improves soil structure and the
water holding capacity of the soil.

Disadvantages of Mulching

 It is a fire risk.
 Provides a breeding ground as well as a hiding place for pests that finally may attack the
crops.
 Traps the light showers of rainfall thus lowering the chances of rain drops reaching the soil.
 It is expensive to acquire, transport and apply.

Routine Field Practices

Thinning

 Removal of excess, weak, damaged or diseased seedlings.

 Allows the remaining seedlings to get enough nutrients and moisture.
 It is aimed at obtaining optimum plant population.

Gapping

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 AGRICULTURE NOTES

 Filling the gaps so as to maintain proper plant population.

 Gaps occur as a result of failure of seeds to germinate or dying of seedlings.
 It should be done early enough for the seedlings to catch up with the other plants

Rogueing

 This is the removal and destruction of a diseased part of a plant or the whole plant.
 The destruction can be achieved through burning of the uprooted plant.

Pruning

 Removal of extra unwanted parts of the plant.

Reasons for pruning are:

 To remove old, unproductive or diseased, damaged parts of the plant.

 To train plants to take a desirable shape for example formative pruning in tea.
 To control crop leave ratio hence avoiding overbearing.
 To control diseases and pests for example antestia bugs in coffee.
 To facilitate other operations such as spraying, picking and seeding.
 To reduce wastage of chemicals applied on the crop.
 To remove branches that interfere with traffic, telephone lines and view.
 Open up the plant to allow free air circulation and exposure of leaves to sunlight.
 Note: Tools used are secateur, pruning saw and pruning knife.

Earthing-up

 This is the placement of soil in form of a heap around the base of the plant.
 It is mostly carried out in tuber crops such as Irish and sweet potatoes to improve tuber
formation.
 It is also carried out in groundnuts and maize.
 In groundnuts it promotes production of pods while in maize it provides support to prevent
lodging.

Crop Protection

Weed Control

 Weeds are plants growing where they are not wanted, that is a plant out of place.
 Such plants include blackjack, couch grass, thorn apple and Mcdonald's eye.
 Such plants should be eradicated or controlled using recommended methods.

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 AGRICULTURE NOTES

Pest Control

 Crop pests are living organisms that are harmful to the crops.
 They include; insects, nematodes, rodents, thrips and mites.
 They cause great damage to crops in the field and stored produce.

Control of Crop Diseases

 A disease is any alteration in the body of an organism and functions of a plant or its parts.
 Disease causing organisms are known as pathogens.
 They include fungi, viruses and bacteria.
 Diseases caused by fungi are referred to as fungal diseases while those caused by viruses and
bacteria are referred to as viral and bacterial respectively.

Harvesting

It is the gathering of the farm produce after maturity.

Time of harvesting depends on:

 Stage of maturity of the crops.

 use of the crop
 tastes and preferences of consumers.
 weather conditions, hence liability to spoilage.

Methods of harvesting is determined by:

 Scale of farming for example large scale farming machines are used.
 Type of crop for example pyrethrum is harvested by hand.
 Uniformity in ripening of the crop for example wheat is harvested by use of combined
harvester while coffee is harvested by hand.
 Uniformity in height of the crop and size of seed, fruits and flowers.
 Financial status of the farmer.
 Part of the plant to be harvested.

Post-Harvest Practices

 These are the preparations carried out on crop produce before it gets to the consumer. They
include;
 Threshing/shelling.
 Drying.
 Cleaning.
 Sorting and grading.
 Dusting.
 Processing.

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 AGRICULTURE NOTES

 Packaging.

Storage

Purpose of storage is to;

 Prevent spoilage
 Make the produce available for future use
 To await good market prices.

Requirements for proper store are:

 It should be clean.
 It should be well ventilated.
 It should be raised from the ground to prevent damp conditions.
 It should be dry.
 It should be strong to hold crop produce.
 It should be easy to clean.
 It should be vermin-proof.
 It should be secure from theft.
 It should be treated against pests such as weevils.

Types of Storage

 Traditional storage structures.

 Modern storage structures.

Preparation of the Store

 Cleaning the store.

 Maintenance
 Dusting the store with appropriate chemicals.
 Clearing the vegetation around the store to keep off vermin.

Crop Production V: (Vegetables)

Introduction

 A vegetable is any crop that is grown and eaten fresh.

 Vegetables are important both for nutritional and commercial reasons.
 They are categorized on the basis of the part used as food. Such parts include;
 Leaves,
 Stems,
 Roots,
 Fruits,
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 AGRICULTURE NOTES

 Flowers,
 Pods
 Bulbs.

Vegetables are grouped into the following categories:

 Leaf vegetables for example kales and cabbages.

 Root vegetables for example carrots, beets, radishes and turnips.
 Fruit vegetables for example French beans and okra.
 Stem vegetables for example asparagus, leeks and spring onions.
 Bulb vegetables for example bulbed onions and garlic.

Tomatoes (Lycopersicon esculentum)

 Tomatoes are fruit vegetables widely grown in Kenya.

 The ripe fruit may be eaten raw cooked or processed to make tomato sauces, juices and pastes.

Ecological Requirements

 Altitude: 0-2100 m above sea level.

 Rainfall: 750-1300 mm per annum.
 Soils: deep, fertile and well drained.

Varieties

Fresh market varieties:

 Money maker,
 Marglobe, hundred fold,
 Beef eater,
 Hot set,
 Super marmande
 Ponderosa.

Processing varieties:

 Kenya beauty,
 San -marzano,
 Roma,
 Heinz 1350,
 Primabel,
 Rutgers hybrid
 Cal-J.

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 AGRICULTURE NOTES

Nursery Practices

 Choose a site which has not been grown Solanaceae crop in the last three years.
 Nursery beds are raised about 15cm above the ground level.
 Make drills of 20cm apart and 1cm deep drill and cover the seeds.
 Provide shade or mulch material.
 Water twice a day.
 Apply phosphatic fertilizers during planting.

Seedbed Preparation

 The land should be dug deeply to control weeds.

Transplanting

 Seedlings are ready for transplanting when they are 10-15cm high after about one month.
 Holes are made at a spacing of 60cm x 90cm.
 Apply 20gm of DSP in the planting hole.
 Transplant with a ball of soil around the roots.
 Apply mulch around each seedling.
 Transplanting is normally in the evening or on a cloudy day.

Field Maintenance

 Early control of weeds is necessary.

 Top dressing is done after crop establishes.
 Pruning and staking are done to train the plants to grow vertically.

Pests Controls

 American Bollworm

> Nature of damage: boring holes on the fruits.

> Control: spraying insecticides.

 Tobacco White Fly

> Nature of damage: suck plant sap from the underside of the leaf, hence may transmit viral
diseases.

> Control: Destroy infected plant and spray insecticides.

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 AGRICULTURE NOTES

Disease Control

 Late Blight

> Cause: Fungus

> Symptoms: dry patches on the leaves and fruits.

> Control: use of fungicides, crop rotation and destruction of affected materials.

 Blossom-end Rot

Caused by;

> Too much nitrogen in early stages.

> Irregular or infrequent watering.

> Calcium deficiency.

> Control: Apply calcium ammonium nitrate and correction of the above problems.

Harvesting

 For canning, fruits should be fully ripe.

 For fresh market, fruits should be partially ripe and packed in crates to avoid damage.
 The fruits should be graded according to;

> Size,

> Colour,

> Ripeness

> Freedom from blemishes.

Cabbage

 It is a leaf vegetable related to other brassica crops such as kales, cauliflower, Chinese cabbage
and Brussels sprouts.
 Cabbage leaves may be eaten raw in salads, steamed, boiled or cooked in a variety of ways.
 The leaves can also be fed to livestock.

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 AGRICULTURE NOTES

Ecological Requirements

 Altitude:

> Those with small heads: 900-15o0m above sea level

> Those with Large heads: 1800-2700m above sea level.

 Temperature: require cool condition.

 Rainfall:

> 750-2000mm per annum.

> Should be well distributed throughout the growing period.

 Soils:

> Deep,

> Fertile

> Well drained.

Varieties

 Earlymaturing:

> Brunswick,

> Sugarloaf,

> Earlyjersey,

> Copenhagen market,

> Chinese cabbage,

> Celerycabbage,

> Cafesplits kool

> Gloria, mukuki,

> Golden acre.

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 AGRICULTURE NOTES

 Late maturing:

> Drumhead,

> Savoy,

> Perfection,

> Winningstadt.

Nursery Practices

 The beds should be raised, dimension 1 m wide and any convenient length (usually 2 3m in
length).
 Make drills of 15-20cm apart.
 Sow seeds by drilling and cover to a depth of 1cm.
 Provide shade or mulch material.
 Apply phosphatic fertilizers and mix thoroughly with soil during planting.
 Water twice a day.

Seedbed Preparation

 Cultivation should be done during the dry season so that all the weeds are killed.
 Dig holes at the spacing of 60cm x 60cm.
 Incorporate farm yard manure in the soil.
 Transplanting
 Water the seedlings before uprooting.
 Seedlings are ready for transplanting after one month that is when they are 10-15cm in height.
 Select healthy and vigorous seedlings.
 Transplant the seedlings with balls of soil to prevent root damage.
 Plant to the same depth as they were in the nursery.

Field Maintenance

 Apply fertilizers during planting and top dress later.

 Control weeds to reduce competition.

Pest Control

 Diamond Black Moth

> Damage: Eats the underside of the leaf making windows or holes in the leaf.

> Control: Spray recommended insecticides.

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 AGRICULTURE NOTES

 Cutworms

> Damage: Attacks the stem at the ground level causing he plant to fall. > Control: Spray
recommended insecticides.

Disease Control

 Black Rot

> Cause: Bacteria

> Symptoms: Leaves turn yellow and rotting of the stem giving an offensive odour,

> Control: Closed season, crop rotation, use certified seeds and spray appropriate chemicals.

 Black Leg

> Cause: Fungus

> Symptoms: Brown to black spots on seedlings and dark canker on the stem.

> Control: crop rotation, destroy infected materials.

Harvesting

 Cabbages are ready for harvesting 3-4 months after transplanting.

 The heads are cut when they are solid and compact.
 Harvested cabbages are sold immediately.

Carrots (Daucus carota)

 It is a root vegetable grown in the cool areas of Kenya.

 It is commonly eaten raw in salads but can also be cooked.

Ecological Requirements

 Altitude: 0-2,9oom above sea level.

 Rainfall:

> 750 -1,000mm.

> Well distributed throughout the growing period.

 Soils:

41
 AGRICULTURE NOTES

> It requires deep,

> Fine tilth

> Well drained soils that are free from obstacles to allow for root expansion.

 Temperatures: it requires cool to warm temperatures as very high temperatures result in the
production of pale and short roots.

Varieties

 Fresh market varieties for example Chantenay and Nantes.

 Canning varieties for example Nantes
 Fodder varieties for example Oxhast.

Land Preparation

 The field should be well dug to a depth of about 20cm.

 The soil clods should be broken to give a fine tilth before planting.
 Manure should not be applied as it induces forking which reduces the crop quality.

Planting

 Carrots are planted directly into the main seedbed.

 Seeds are drilled into rows made 20-30cm apart.
 The seeds are then covered lightly and the soil pressed down.
 90kg/ha of DSP should be applied at planting time in the drills.
 It should be mixed well with the soils before placing the seeds.

Field Practice

 Thinning - it is done 2 weeks after germination.

 Weed control- the field should be kept weed free.
 Earthing up should be done while weeding to encourage root expansion ..
 Topdressing: after weeding 60kg of nitrogen per hectare should be applied as top dress.
 Irrigation - this should be carried out where or when there is not enough rainfall.

Pest Control

 Carrots do not have many field pests except the green aphids.
 These can be controlled by use of the appropriate pesticides.

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 AGRICULTURE NOTES

Disease Control

 Occasionally attached by the mildews especially in wet and humid

 environment. Thinning can be done to reduce humid conditions.

Harvesting and Marketing

 Carrots are ready for harvesting 3-5 months after planting depending on the variety.
 They are lifted from the soil and sold fresh or canned.

Onions (Allium cepa)

 Onions are bulb vegetables grown in the warm areas of Kenya.

 They are used as a vegetable in salads and for flavouring foods, soups and stews.

Ecological Requirements

 Altitude: 0-2, 100m above sea level.

 Rainfall:

> 1,ooomm of rain per year

> irrigation in dry areas .

 Soils:

> Requires well drained fertile soils

> pH of 6.0 - 7.0.

 Temperatures:

> Onions are a warm climate crops.

> However, some varieties prefer cool conditions.

 They require a fairly long dry period for ripening.

Varieties

 Red creole,
 Tropicana hybrid
 White creole.

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 AGRICULTURE NOTES

Land Preparation

 The land should be well prepared leaving a fine tilth.

 Farm yard manure at 40 - 50 tonnes per hectare should be applied and mixed with the soil.

Planting

 Direct: Seeds are drilled in rows 30cm apart and 8cm within the rows. 20kg/ha of DSP
fertilizer is used.
 Indirect: Seeds are established in the nurseries before transplanting them in rows 30cm apart
and 8 cm within the rows.
 Shallow planting is recommended for bulb expansion.

Field Management Practices

Thinning

 It is carried out only in the crop that has been directly planted so as to achieve spacing of 8cm
between two plants within the row.
 The thinned plants referred to as spring onions are used as vegetables in salads.

Topdressing

 Calcium ammonium nitrate at the rate of 25okg per hectare is recommended for topdressing
onions.
 This is done 3 months after planting.

Pest Control

Onion Thrips:

 These cause silvering and withering of leaves from the tips downwards.
 They are controlled by spraying with appropriate insecticides such as Diazinon or fenthion.

Disease Control

Purple Blotch and Downey Mildew

 Purple blotch;

> Characterized by oval greyish lesions with purple centres on leaves.

> This causes leaf curling and die back.

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 AGRICULTURE NOTES

 Downey mildew;

> Characterized by brown spores covering the leaves leading to death of the whole plant.

> The two diseases are effectively controlled by crop rotation and application of appropriate
fungicides.

Harvesting and Marketing

 Onions are ready for harvesting 5 months after planting.

 When leaves start drying the tops are broken or bent at the neck.
 This hastens the withering of the stems.
 The bulbs are then dug out and left to dry in a shade for a few days.
 Onions are graded according to size and marketed in nets of about 14 -16kgs.

Livestock Health I

(Introduction to Livestock Health)

Introduction

 Health is the state of the body in which all the organs and systems are normal and functioning
normally.
 Disease is any deviation from the normal health of the animal.

Importance of Keeping Livestock Healthy:

 Healthy animals give high income due to low treatment costs.

 The productive life span of a healthy animal is longer.
 High production.
 Healthy animals can multiply regularly.
 Healthy animals give high quality products for example eggs.
 Safety of consumers of livestock products.

Predisposing Factors to Livestock Diseases

 These are conditions within or around the animal that make it easy for an animal to contract a
disease.

They include:

 Animal factors such as;

> species,

45
 AGRICULTURE NOTES

> breed,

> age,

> sex

> colour of the animal.

 Environmental factors such as;

> chilling,

> being rained on,

> exposure to hot sun

> dampness.

 Management factors such as;

> poor feeding,

> housing,

> handling

> hygiene,

> overcrowding .

Signs of ILL-Health in Livestock

 Abnormal behaviour for example separation from the rest of the herd and restlessness.
 Abnormal posture for example limping and lameness.
 Alimentary canal disfunction such as blood stained faeces and abnormal defecation, diarrhoea
and dysentery.
 Urination: high frequency or too low and having strange colour.
 Skin: rough with scaly skin, blisters on the skin and hair loss.

Causes of Diseases

Pathogenic causes ;

> viruses,

> rickettsia,

46
 AGRICULTURE NOTES

> bacteria,

> protozoa

> fungi.

Physical causes;

> fractures,

> dislocation,

> sprains .

 Nutritional disorders for example milk fever.

 Chemical causes for example poisoning by agrochemicals.

Categories of Diseases

 Notifiable diseases ;

> These are diseases which cause high economic losses.

> Any case should be reported to the Chiefs, D.O.s, veterinary officers or the police.

 Tick-borne diseases - Transmitted by ticks.

 Breeding diseases - Transmitted through mating.
 Nutritional diseases for example milk fever and bloat.
 Parasitic diseases for example ascariosis.

General Methods of Disease Control

 Quarantine.
 Vaccination.
 Control of vectors by use of acaricides and rotational grazing.
 Disinfecting the equipment and buildings.
 Use of preventive drugs.
 Proper feeding of livestock.
 Culling of the animals which are carriers/slaughtering the affected animals.
 Use of artificial insemination to control breeding diseases.
 Proper selection and breeding of animals.
 Proper housing and hygiene,
 Isolating sick animals.

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 AGRICULTURE NOTES

Appropriate Methods of Handling Livestock

Animals are handled for the following reasons:

 When inspecting the animal to ascertain any abnormality or signs of diseases.

 When administering any form of treatment such as drenching, injection and mastitis control.
 When spraying or hand dressing the animal with chemicals to control external parasites.
 When milking the animal.
 When performing some of the management practices such as dehorning, disbudding,
castration, hoof trimming .
 When carrying out these activities animals should be restrained in a crush.

Other methods of restraining animals include the use of;

 halters,
 ropes,
 bull ring
 lead stick.

Livestock Health ll (Parasites)

Introduction

 A parasite is an organism which obtains its livelihood from another organism (host) which
suffers damage.
 Parasitism is the association between a parasite and a host.

The effects of parasite on the host animal are:

 Depriving the host of its food.

 Sucking blood.
 Damaging the organs of the host.
 Cause irritation on the skin of the host.
 Destruction of hides and skins.
 Transmission of diseases.
 Cause obstruction in body passages.

General Symptoms of Parasites infestation:

 Emaciation.
 Pot bellied condition.
 Swellings in the jaw or other areas.
 Rough hair or rough coat.
 Anaemia.
 Diarrhoea.
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 AGRICULTURE NOTES

 Presence of worm segments and blood stains in the defecation.

Types of Parasites

There are two types of parasites:

 External (ecto-parasites)
 Internal(endo-parasites)

External parasites are;

 ticks,
 tsetse flies,
 mites,
 lice,
 fleas
 keds

Life Cycle of ticks

 Eggs are laid in cracks on the ground.

 They hatch in 4-6 weeks into larvae which climb on the grass waiting for a passing animal.

One-Host Tick

 This requires one host to complete its life cycle.

 Example: blue tick (Boophilus decoloratus).
 Preferred sites: face, neck, dewlap and side of the body.
 Disease transmitted: Redwater and anaplasmosis.

Two-Host Tick

 This requires two different hosts to complete its life cycle.

 Example: The red legged tick (Rhipicephalus everts)
 Preferred sites: Ears, anus, udder and the tail.
 Disease transmitted: Redwater and east coast fever.
 Example: Bont legged tick (amblyomma spp.)
 Preferred sites: Udder, scrotum and tail switch.
 Disease transmitted: Sweating sickness.

Three-Host Tick

 This requires three hosts to complete its life cycle.

 Example: The brown ear tick (Rhipicephalus appendiculatus)
 Preferred sites: Ears, tail switch and around the eyes.
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 AGRICULTURE NOTES

 Disease transmitted: East coast fever and redwater.

 Bont tick transmit heartwater (amblyomma spp.)

Control of Ticks

 Dipping/spraying/hand dressing with acaricides.

 Rotational grazing.
 Ploughing the land to break the life cycle.
 Hand picking and killing.
 Fencing of the grazing fields to keep off other animals including wild game.
 Burning of grass to kill them in various stages.

Endo-parasites ( internal Parasites)

 Endoparasites are helminths.

They can be divided into:

 Platyhelminthes/flatworms which include;

> Trematodes (flukes)

> Cestodes (tapeworms).

 Nemato-helminthes/nematodes. E.g Roundworms.

General Symptoms of Helminthiasis

 Diarrhoea which foul the anal and tail region.

 Dullness.
 Anaemia.
 Big stomach (pot bellied condition).
 Presence of worm segments in faeces.
 Coughing.

Trematodes (Liver Fluke)

There are two species of flukes:

> Fasciola gigantica

> Fasciola hepatica.

Fasciola hepatica is more common.

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 AGRICULTURE NOTES

It is commonly found in the liver and bile duct of cattle, sheep and goats.

Liver fluke is a problem in marshy and low lying wet areas.

Life Cycle of the Liver Fluke

 Adult fluke in the liver of the primary host lays eggs.

 Eggs pass through the bile duct into the small intestines and are passed out in faeces onto the
pasture.
 Under moist conditions, they hatch into a miracidium larva which swims about in search of a
secondary host (fresh water snails).
 In the snail, it develops through sporocyst, redia and cercaria.
 When it leaves the snail, the cercaria gets encysted on vegetation and becomes metacercaria.
 This is swallowed by the primary host with grass.
 The young fluke migrates into the liver through blood vessels when it matures.

Control of Liver Fluke

 Keep livestock off marshy areas near the rivers/streams/lakes and dams.
 Drench af-fected animals.
 Drainage of swampy areas.
 Eradicate the intermediate host by use of molluscicides.
 Provide water to livestock in elevated troughs.

Tapeworms

 There are many species of tapeworms

Example;

Taenia solium

Taenia saginata.

 The adults live in the small intestines of man (the primary host).
 The intermediate host of Taenia solium is pig .
 The intermediate host of Taenia saginata is cattle.

Life Cycle of Tapeworm

 Adult tapeworms live in man's intestines where it lays eggs.

 Eggs are passed out with faeces,
 Then they develop an outer covering known as onchosphere.
 The eggs are swallowed by intermediate host.
 The outer covering is digested and the young worm emerges.

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 AGRICULTURE NOTES

 This bores into the blood vessels and is carried to specific muscles such as the tongue, heart,
thigh muscles.
 It develops into an encysted form called bladder-worm.
 When the animal is killed and meat is eaten raw or in an inadequately cooked form, man gets
infected by the bladder-worm.
 In man, the bladder-worm evaginates and attaches itself onto the intestinal wall where it
develops into an adult.

Control of Tapeworms

 Meat should be well cooked before eating.

 Use of drugs in primary host.
 Meat inspection by meat inspectors] veterinary officers.
 Use of pit latrines by man.

Nematodes (Roundworms)

Common ones are;

 Ascaris suum (pig roundworms),

 Ascaris lumbricoides found in man and sheep
 Haemonchus contortus found in sheep, cattle and goats.
 Roundworms are common in warm areas especially in areas where the standards of hygiene
and sanitation are low.

Nature of Damage

 Damage is done to the liver and lung tissues as they migrate in the body.
 Suck out blood.
 Deprive the host of food.

Control of Roundworms

 Use of drugs.
 Rotational grazing.
 Use of proper stocking rates to avoid overgrazing.
 Practising high standards of cleanliness and hygiene such as use of latrines.

Livestock Production ll (Nutrition)

Introduction

 Animals are fed for the purpose of production and body maintenance.
 The edible material given to animals is called food.
 It is digested, absorbed and~ utilized in the body.

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 AGRICULTURE NOTES

 Nutrients are organic and inorganic substances contained in the food materials

Components of Food material

 water, protein,
 carbohydrates,
 fats and oils,
 vitamins
 mineral salts.

Water

Sources

 Free water (through drinking)

 Bound water (contained in feeds).
 Metabolic water (obtained from oxidation of food).

Functions

 Regulates body temperature.

 Transport agent in the body.
 Universal solvent in the body.
 Gives shape to the cells (turgidity).
 Acts as a lubricant.
 Acts as constituent of body fluids.

Factors Determining the Requirements of Water by Livestock

 Production level.
 Amount of dry matter eaten.
 Temperature of the surrounding area.
 Type of animal.
 Type of food eaten.

Protein

Sources:

 Groundnut cakes,
 cotton seed cakes,
 fish meal,
 meat meal.

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 AGRICULTURE NOTES

Functions:

 Growth of new tissues.

 Repair of worn out tissues (body building).
 Synthesis of antibodies.
 Synthesis of hormones and enzymes.
 Production of energy during starvation.

Digestion of Proteins

In non-ruminants, protein digestion takes placed in the stomach.

 Food is subjected to mechanical breakdown through chewing into small particles.

 Protein is acted on by enzymes to turn into amino acid which is assimilated into the
bloodstream.

In ruminants, protein digestion initially takes place in the rumen.

 Food is acted on by micro-organisms into microbial protein.

 Later, enzymatic action takes place in the "true stomach" or abomasum where proteins are
broken down into amino acids which are then assimilated into the bloodstream.

Carbohydrates

Sources:

 Cereals,
 tubers
 commercially mixed feeds.

Functions:

 Supply energy and heat to the body.

 Excess is stored in form of fat for insulation of the body.

Digestion of Carbohydrates

 In non-ruminants;

> carbohydrate feeds are broken down by chewing into small particles.

> Then enzymatic action further breaks down carbohydrates into glucose, fructose and galactose
which are then assimilated into the bloodstream.

 In ruminants;

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 AGRICULTURE NOTES

> mechanical breakdown of carbohydrate feeds is followed by microbial activities which break
down cellulose into volatile fatty acids.

> These are absorbed through the rumen walls.

> Some carbohydrates are broken down by enzymatic action in the "true stomach" or abomasum.

Fats and Oils

Sources:

 Cotton seeds,
 soya beans
 groundnuts.

Functions:

 Supply energy and heat to the body.

 Excess is stored as fat adipose tissues.
 Source of metabolic water in the body.
 Required for the development of neural system.
 Insulator in the body.

Digestion of lipids in Ruminants

 Fats are hydrolysed in the rumen into fatty acids and glycerol.
 Others are fermented into propionic acid,
 The shorter chains are passed to the true stomach where enzymatic action takes place.

Vitamins

Sources:

 Green materials,
 dried grass
 fishliveroil.

Functions:

 Protects the body against diseases.

 Regulate the functions of all parts of the body.
 It acts as a co-enzyme in the body.

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 AGRICULTURE NOTES

Examples:

 Vitamin A,
 vitamin B2
 vitamin C,
 vitamin E
 vitamin K.

Minerals

Sources:

 Salt licks,
 bone meal,
 legumes
 cereals.

Functions:

 Form part of the tissues such as bones and teeth.

 Work together with the enzymes.
 Act as acid -base balances. Act as
 electrolyte in the body. Regulate
 osmotic balance in the body.

Examples:

 Calcium,
 phosphorus,
 magnesium,
 iron,
 iodine,
 sodium
 chlorine.

> Calcium and phosphorus

 Needed for teeth and bone formation.

 Lack of these minerals leads to rickets, osteomalacia.

> Lack of iron leads to anaemia.

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 AGRICULTURE NOTES

Classification of Animal Feeds

 This is based on nutrient composition:

 Roughages.
 Concentrates.
 Feed additives.

Roughages

 Are feeds of low available nutrients per unit weight and high fibre content

Examples:

 Dry roughages,
 succulent roughages,
 residues from agricultural by products and conserved materials.

Characteristics

 Low level of available nutrients.

 Have high level of calcium especially legumes.
 Good source of vitamin A.
 Have high fibre content.

Concentrates

 Are feeds of high available nutrients per unit weight.

Examples:

 Maize germ and bran,

 malt extract,
 milk products,
 soyabeans,
 oil seed cakes,
 meat meal,
 bonemeal
 bloodmeal.

Characteristics

 Low fibre content.

 Feed content is consistently high.
 High digestibility of the feed.
 High in nutrient content.
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 AGRICULTURE NOTES

Feed Additives

 These are substances added to the feed to increase;

 palatability,
 medication
 or hormones to make animals produce more.

There are two types:

 Nutritive additives, such as mineral licks (maclick).

 Non-nutritives additives, such as;

> medicants (coccidiostats),

> Stilboestrol (used in beef animals)

> oxytocin (to increase milk let down).

Functions

 Stimulate growth and production.

 Improve feed efficiency.
 Prevent disease causing organisms.

Compounded Feeds

 These are the feeds prepared and mixed by use of machines.

 These feeds can be round, pelleted, pencils, cubes or mash.

Poultry feeds can be categorized as:

 Chick mash having 20% D.C.P. given to chicks.

 Growers mash having 16% D.C.P. given to growers.
 Layers mash having 12-15% D.C.P. given to layers.

Meaning of terms used to express feed values

 Nutritive ratio (NR):

> ls the proportion of protein to carbohydrates and fats.

> In young animals 13:6

> In old animals 1:8.

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 AGRICULTURE NOTES

 Crude protein (C.P): ls the total amount of protein contained in a feed.

 Digestible Crude Protein (D.C.P): Is the portion of crude protein which an animal is capable
of digesting.
 Crude Fibre (C.F.):

> ls the total amount of fibre contained in a feed.

> It is mainly lignin and cellulose.

 Digestible Fibre (D.F.): ls the portion of the total fibre contained in a teed which an animal is
capable of digesting.
 Dry Matter (D.M.): ls the material left in a feed after water has been removed.
 Starch equivalent (S.E.): ls the amount of pure starch which has the same energy as 100kg of
that feed.
 Total Digestible Nutrients (T.D.N.): ls the sum of all the digestible organic nutrients such as
fats, proteins, carbohydrates and fibre.

Computation of Livestock Rations

Ration:

> Is the amount of food that will provide essential nutrients to an animal in a 24 hour period > to
enable that animal to meet its maintenance and production requirements.

Balanced ration:

> ls the ration that contains all the essential nutrients in required amounts and in the right
proportion.

Maintenance ration:

> is the portion of a feed required by an animal to continue with the vital body processes with no
loss or gain in weight.

Production ration:

> ls the feed required by animals over and above maintenance ration to enable the animal to
produce; > for example; milk, eggs, wool, grow in size, perform work, reproduce and fatten.

Steps in ration formulation

 Finding out the animal's feed requirement based on body weight.

 List all the available feeds, with their nutrient composition and their prices.
 Calculate the amount of ingredients required in the ration to meet the animals needs.

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 AGRICULTURE NOTES

Methods used in ration formulation

 Trial and error method

 Pearson’s square method
 Graphical method
 Linear programming(use of computers)

Examples;

Mix a Pigs ration 22% protein using soya bean meal 40% DCP and maize meal containing
8%DCP.

Pearson's square method

Digestion and digestive systems

 Digestion is the process through which food is broken down into small particles in the
alimentary canal ready for absorption into the blood stream.

Digestion of food in livestock takes place in three stages;

 Mechanical breakdown and chewing

 Microbial breakdown by bacteria and protozoa in the rumen of ruminants
 Chemical breakdown by enzymes.

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 AGRICULTURE NOTES

Digestive system of a Ruminant

Rumen:

 Breakdown of food by micro-organisms and also stores food.

 Synthesis of vitamin B-complex.
 Synthesis of amino acids from ammonia gas.
 Proteins are broken to peptides and amino acids.
 Carbohydrates are broken to volatile fatty acids.

Reticulum:

 Separates large food particles from the small particles.

 Retains foreign materials such as stones, hard wood and sand.

Omasum:

 Breaks up food by grinding.

 Reduction of water content from the feed stuff.

Abomasum:

 Enzymatic digestion takes place here ..

 Contains some microbes which digest cellulose.
 Breaks up food by grinding.
 It is also found in non-ruminants.

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 AGRICULTURE NOTES

Digestive system of a non-ruminant e.g pig

Comparison Between Digestion in Ruminant and Non- ruminants

Differences

Ruminants

 Chew the cud.

 Have four stomach chambersthus polygastric.
 Regurgitate food.
 Can digest cellulose. Have micro-organisms in the rumen that digest cellulose.
 Have no Ptyalin in saliva hence
 no enzymatic digestion in the mouth.
 Most digestion and absorption takes place in the rumen.
 Have alkaline saliva due to presence of ammonia.

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 AGRICULTURE NOTES

Non -ruminants

 Do not chew the cud.

 Have one stomach chamber - thus monogastric.
 Cannot regurgitate food once swallowed.
 Have no micro-organisms in the stomach hence cannot digest cellulose except those animals
with micro-organisms in the caecum.
 Have Ptyalin in the saliva hence enzymatic digestion starts in the mouth
 Most digestion and absorption takes in the small intestines.
 The saliva is neutral pH.

Digestion system of poultry

Functions of the Parts of Poultry

 Crop:

> Storage of food.

> Softening of food by secretions from small glands in the walls.

 Proventriculus: Enzymes start the breakdown of food.

 Gizzard:-Crushes and grinds the coarse food (has small grit and gravel).

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 AGRICULTURE NOTES

Comparison Between Digestion In Ruminants and Non-Ruminants

Similarities Between Digestion In Ruminants and Non-Ruminants

 Digestion in young ruminants is similar to that in non-ruminants as they do not have a

developed rumen-reticulum complex.
 Final protein digestion takes place in the small intestines in both cases.
 Water absorption takes place in the colon in both ruminants and non ruminants

Soil Fertility II

(Inorganic Fertilizers)

Introduction

• Plant nutrients occur in the soil in form of soluble substances.

• These substances are taken in by the plants in different quantities depending on their roles in
the plant tissues.

Essential Elements

• These are nutrients needed by plants for various uses.

• They are divided into two broad categories namely:

- Macronutrients

- micronutrients.

Macro-nutrients

• These are also referred to as major nutrients.

• They are required by the plant in large quantities.

They include;

• carbon,

• hydrogen,

• oxygen,

• nitrogen,

• phophorus,

• potassium,

• sulphur,

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 AGRICULTURE NOTES

• calcium

• magnesium.

- Nitrogen, phosphorus and potassium are referred to as fertilizer elements,

- Calcium, magnesium and sulphur, are referred to as liming elements.

Role of Macronutrients in Plants

Nitrogen (NO 3 ,NH4 + + )

Sources:

• Artificial fertilizers

• Organic matter

• Atmospheric fixation by lightning

• Nitrogen fixing bacteria.

Role of Nitrogen in Plants

• Vegetative growth

• Chlorophyll formation

• Build up of protoplasm.

• Improves leaf quality in leafy c rops such as tea and cabbages.

Deficiency Symptoms

• Yellowing of the leaves/chlorosis.

• Stunted growth.

• Premature ripening.

• Premature shedding of the leaves.

• Light seeds.

Effect of Excess Nitrogen

• Scorching of the leaves.

• Delayed maturity.

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 AGRICULTURE NOTES

Loss of Nitrogen From the Soil:

• Soil erosion.

• Leaching.

• Volatilization.

• Crop removal.

• Used by microorganisms.

Phosphorus (H 2 P0 4 , HPO 2 - 4 P 2 O 5 )

Sources:

• Organic manures

• Commercial fertilizers

• Phosphate rocks

Role of Phosphorus

• Encourages fast growth of the roots.

• Improves the quality of the plant.

• Hastens maturity of the crops.

• Influences cell division.

• Stimulates nodule formation in legumes.

Deficiency symptoms

• Growth of the plant is slow.

• Maturity is delayed.

• Leaves become grey, purple in colour.

• Yield of grains, fruits and seed is lowered.

Loss of Phosphorus From the Soil

• Soil erosion.

• Leaching

• Crop removal

• Fixation by iron and aluminium oxide.

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 AGRICULTURE NOTES

Potasium (K+, K 2 O)

Sources;

• Crop residue and organic manures.

• Commercial fertilizers

• Potassium bearing minerals e.g. feldspar and mica.

Role of Potassium in Plants

• Increases plant vigour and disease resistance.

• Increases the size of grains and seeds.

• Reduces the ill-effects due to excess nitrogen.

• Prevents too rapid maturation due to phosphorus.

Deficiency Symptoms

• Plants have short joints and poor growth.

• Plants lodge before maturing.

• Leaves develop a burnt appearance on the margin.

• Leaves at the lower end of the plant become mottled, spotted or streaked.

• In maize, grains and grasses firing starts at the tip of the leaf and proceeds from the edge
usually leaving the midrib green.

Loss of Potassium From the Soil

• Crop removal.

• Leaching.

• Soil erosion.

• Fixation in the soil.

Calcium (Ca 2 +)

Source:

• Crop residues and organic manures.

• Commercial fertilizers.

• weathering of soil minerals.

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 AGRICULTURE NOTES

• Agricultural limes for example dolomite, limestone.

Role of Calcium in Plants

• Improves the vigour and stiffness of straw.

• Neutralizes the poisonous secretions of the plants.

• Helps in grain and seed formation.

• Improves the soil structure.

• Promotes bacterial activity in the soil.

• Corrects the soil acidity.

Deficiency symptoms

• Young leaves remain closed.

• There are light green bands along the margins of the leaves.

• Leaves in the terminal bud become hooked in appearance there is a die -¬back at the tip and
along the margins.

Loss of Calcium

• Crop removal

• Leaching

• Soil erosion

Magnesium (Mg 2+ )

Sources:

• Crop residues and organic manures

• Commercial fertilizers

• Weathering of soil minerals.

• Agricultural limes.

Role of Magnesium in Plants

• Forms part of chlorophyll.

• Promotes the growth of the soil bacteria and enhances the nitrogen fixing power of the
legumes.

• Activates the production and transpor t of carbohydrates and proteins in the growing plant.

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 AGRICULTURE NOTES

Deficiency symptoms

• Loss in green colour which starts from the bottom leaves and gradually moves upwards.

• The veins remain green.

• Leaves curve upwards along the margins.

• Stalks become weak and the plant develops long branched roots.

• The leaves become streaked.

2-
Sulphur (S0 4 ,SO 2 )

Sources:

• Commercial fertilizers.

• Soil mineral containing sulphides

• Atmospheric sulphur from industries.

• Rain water

Role of Sulphur in Plants

• Formation and activation of coenzyme-A.

• Sulphur is a constituent of amino acids.

• Influence plant physiological processes.

Deficiency Symptoms

• Small plants/stunted growth.

• Poor nodulation in legumes.

• Light green to yellowish leaves/ chlorosis.

• Delayed maturity.

Micro-nutrients

• Also referred to as trace or minor nutrients.

• They are required in small quantities/traces.

• They are essential for proper growth and development of plants.

They include;

• Iron,

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 AGRICULTURE NOTES

• Manganese,

• Copper,

• Boron,

• Molybdenum

• Chlorine.

Role of Micronutrients and Their Deficiency Symptoms

• Copper

- Role in oxidation-reduction reactions.

- Respiration and utilization of iron

- Deficiency symptoms-yellowing of young leaves.

• Iron

- Synthesis of proteins.

- Takes part in oxidation-¬reduction reactions.

- Deficiency symptoms - leaf chlorosis

• Molybdenum

- Nitrogen transformation in plants.

- Metabolization of nitrates to amino acids and proteins

- Deficiency symptoms -leaf curl and scathing.

• Manganese - Same as molybdenum.

• Zinc

- Formation of growth hormone.

- Reproduction process

- Deficiency symptoms - white bud formation.

• Boron

- Absorption of water.

- Translocation of sugar

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 AGRICULTURE NOTES

Inorganic Fertilizers

• These are chemically produced substances added to the soil to improve fertility. Classification
According to:

• Nutrients contained

- Straight - contain only one macronutrient.

- Compound fertilizers - contain more than one macronutrient

• Time of application

- Some applied when planting.

- Top dressing after crop emergence

• Effects on the soil pH.

- Acidic fertilizers.

- Neutral fertilizers.

- Basic fertilizers.

Properties and Identification of Fertilizers

Nitrogenous Fertilizers

Characteristics

• Highly soluble in water.

• Highly mobile in the soil hence it is applied as a top dress.

• Easily leached because of the high solubility hence does not have residual effect on the soil.

• Has scorching effect on young crops during wet seasons.

• Easy to volatilize during hot season.

• They have a tendency to cake under moist conditions.

• They are hygroscopic hence should be stored in dry conditions.

Examples:

• Sulphate of Ammonia (NH 4 ) 2 SO 4

• Physical appearance:

- white crystals,

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 AGRICULTURE NOTES

- Has acidic effect,

- Contains 20% N.

• Ammonium Sulphate Nitrate [(NH 4 )2 SO 4+ NH 4 NO 3 ]

- Colour: granules which appear yellow orange,

- less acidic,

- contains 26% N.

• Calcium Ammonium Nitrate (CAN)

- Colour: greyish granules,

- neutral in nature,

- contains 21 % N.

• Urea

- Colour: small whitish granules

- Easily leached or volatilized,

- contains 45- 46%N.

Phosphate Fertilizers

• Has low solubility and immobile.

• Non-scorching.

• Has a high residual effect hence benefit the next season's crop.

• Easy to store because they are not hygroscopic.

Examples;

• Single super-phosphate

- Appearance: whitish, creamy white granules,

- contains 20-21 % P 2 O 5

• Double super-phosphate

- Appearance: dark greyish granules,

- Contains 40-42% P 2 O 5

• Triple super-phosphate

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 AGRICULTURE NOTES

- Appearance: small greyish granules,

- Contain 44-48% P 2 O 5

Potassic Fertilizers

Characteristics:

• Has moderate scorching effect.

• Moderately soluble in water.

• Most Kenyan soils have sufficient potassium.

Examples;

• Muriate of Potash (KCl)

- Contain 60 - 62% K 2 O

- Slightly hygroscopic.

- Appearance amorphous white.

• Sulphate of Potash (50% K 2 O)

Compound or Mixed Fertilizers

• These are fertilizers which supply 2 or more of the macronutrients.

Examples;

• Mono ammonium phosphate.

• Di-ammonium phosphate

• 20:20:20, 23:23:23

Advantages of application of compound fertilizers

• Saves time and money.

• Mixture gives improved storage properties and better handling.

Disadvantages of compound fertilizers application

• Expensive.

• Wasteful.

• Mixing may not be thorough.

• Incompatibility of the individual fertilizers.

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 AGRICULTURE NOTES

Methods of fertilizer application

• Broadcasting - random scattering of the fertilizers on the ground.

• Placement method - application of fertilizers in the planting holes.

• Side dressing - fertilizer is placed at the side of the plant within the root zone, in bands or
spot-rings.

• Foliar spraying - specially formulated fertilizer solution applied on the foliage in spray form.

• Drip method - applied through irrigation water.

Determination of Fertilizer Rates

Contents of fertilizers are expressed as fertilizer grade or fertilizer analysis.

• Fertilizer grade indicate the guaranteed minimum of the active ingredients (N, P 2 O5, K 2 O) in
the mixture.

• It is expressed as a percentage on a weight to weight basis or percentage by weigh

Example 10:20:0 means for every 10kg of the mixture there are 10kg of nitr ogen, 20kg of P2O
5 and 0kg of K 2 O.

Example

A farmer was asked to apply fertilizers as follows:

• 60 kg/ha nitrogen (top dressing)

• 60 kg/ha P2O5 (in planting hole).

• 60 kg/ha K2O.

How much sulphate of ammonia (20%) would be required per hectare?

How much double super-phosphate (40%) P2O5would be required per hectare?

How much muriate of potash (50% K2O) would be required per hectare?

Answer/Solution

• Sulphate of ammonia (SA) which gives 60kg/ha N = 60

20x 100 =300kg SA

• Double super phosphate (40% P 2 O 5 )which gives 60kg/ha P 2 O 5 60

= 40x 100 =150kg DSP

• Muriate of potash (60% K2O) which gives 60kg/hK 2 O

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 AGRICULTURE NOTES

= 60 x 100=100kg muriate of potash

60

Example

A farmer was asked to apply fertilizers as follows:

• 200kg/ha of DSP (40% P 2 O 5

• 150kg/ha of muriate of potash (60% K 2 O)

• 150kg/ha of sulphate of ammonia (20% N)

How much P 2 O 5 did the farmer apply per acre?

How much K 2 O did the farmer apply per hectare?

How much N did the farmer apply per hectare?

Solution/Answer

• P 2 O 5 applied per hectare from 200kg of DSP 40

= 100x 200= 80kg/ha P 2 O 5

• K 2O 5 applied per hectare from 150kg of muriate of potash 60

= 100x150=90kg/ha K 2 O

• N applied per hectare from 150kg/ha sulphate of ammonia 20

= 100 x 150= 30kg/ha N

Soil Sampling

• Refers to obtaining of small quantity of soi l that is representative in all aspects of the entire
farm.

Soil Sampling Procedures

• Clear the vegetation over the site.

• Dig out soil at depths of 15-25cm.

• Place the dug out soil in a clean container.

• Mix thoroughly the soil in the container.

• Take a sample and send it to National Agricultural Laboratory for analysis.

• The container carrying the sample should be properly labeled as follows:

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 AGRICULTURE NOTES

- Name of the farmer,

- Location,

- District

- Address of the farmer.

Sites to Avoid

• Dead furrows, ditches.

• Swamps

• Near manure heaps.

• Recently fertilized fields

• Ant hills.

• Under big trees.

• Near fence lines or foot paths.

• Do not put them in containers which are contaminated with fertilizers or other chemical
containers.

Methods Of Soil Sampling:

• Zigzag method

• Traverse method

Soil Testing

• Soil testing is the analyzing of the soil sample to determine certain qualities of the soil.

Importance of Soil testing:

• To determine the value of the soil hence determine the crop to grow.

• To determine the nutrient content hence find out the type of fertilizer to apply.

• To determine whether it is necessary to modify the soil pH for a crop.

How Soil pH affects Crop Production

• Influences the physical and chemical properties of the soil.

• Affects the availability of nutrients.

• Influences the incidences of soil borne diseases.

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 AGRICULTURE NOTES

• Determine the type of crop to be grown at a given area.

Methods of pH Testing

• Universal indicator solution

• pH meter

- Know the course of action to be taken in the event of a disease and maintenance of good
health.

- Know the prevalent diseases.

- Calculate the cost of treatment.

• Marketing Records show commodities sold, quantities and value of all the sales. Labour
Records - show labour utilization and labour costs.

Crop production II (Planting)

• Planting is the placement of the planting material in the soil for the purpose of regeneration in
order to produce more of the plant species.

Types of planting materials

Seeds

• Seeds are produced by flowering after pollination and fertilization.

They contain the part of the plant that germinates and subsequently grows in to new plants.

Advantages of using seeds as planting materials.

• Seeds are easily treated against soil borne pests and diseases.

• They are not bulky therefore storage is easy.

• They are easy to handle during planting making operation easy.

• When planting seeds, it is easy to use machines like seed planters and drillers.

• It is easy to apply manures and fertilizers together with seeds during planting.

• Fertilizers and manures application can be easily mechanized.

• It is possible to develop new crop varieties due to cross pollination.

Disantivantages of using seeds as planting materials.

• Some seeds have long dormancy and they may need special treatment in order to germinate.

• Plants raised from seeds have variations from the mother plant due to cross pollination, This
may introduce undesirable characteristics.

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 AGRICULTURE NOTES

• Soil borne pests may damage seeds if left for sometime in the soil before rain falls.

• Some seeds may lose viability if stored for a long time. This leads to gaps in the farm.

1. Vegetative materials.

• These are plant parts which have the ability to produce roots, they grow and develop in to
new plants.

• Plant parts such as leaves, roots or stems can be used for planting as long as they are capable
of rooting.

Advantages of using vegetative materials for planting.

• Crops originating from vegetative materials matures faster than those from seeds.

• The crops shows uniformity in such qualities as diseas e resistance, seed size, colour, keeping
or storing quality and chemical composition.

• It is possible to produce many varieties of compatible crops on the same root stock.

• Use of the vegetative materials is easier and faster, especially where seeds show prolonged
dormancy.

• The resulting plant has desired shape and size for ease of harvesting and spraying.

• It facilitates the propagation of crops which are seedless or those that produce seeds which
are not viable or have a long dormancy period.

• Such crops include sugar-cane, bananas, Napier grass and others.

Disadvantages.

• Vegetative propagation does not result in new crop varieties.

• Keeping the materials free of diseases is difficult.

• Materials cannot be stored for long.

• The materials are bulky and there fore difficult to store and transport. Plant parts used for
vegetative propagation.

i) Bulbils.

• These are tiny sisal plants produced in the inflorescence almost at the end of the plant growth
cycle.

• They resemble the mother plant except th at they are smaller in size.

• They are produced by the branches of the sisal pole.

• When manure they mature they develop rudimentary roots and fall off to the ground just
below the pole.

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 AGRICULTURE NOTES

• They are the collected and raised in the nurseries before they ar e transplanted t\o the main
field.

• One sisal pole may produce as many as 3,000 bulbils. They are usually 10cm long. They make
good planting materials and are better than sucke

ii) Splits

• These are plantlets divided from the existing mother plant with c omplete with complete leaves
and rooting system.

• They are used to propagate most pasture grasses and pyrethrum.

• Pyrethrum splits are raised first in nursery and then transplanted to the field.

iii) Crowns and slips

• These are materials used to propaga te pineapples

• Crowns are born on top of the fruits and are broken off and prepared for planting.

• They are more preferred to suckers because they give uniform growth and take two years to
reach maturity.

• Slips are borne to the base of the pineapple fr uits.

• They are cut and prepared for plantings.

• Their growth rate is faster than for crowns giving average uniformity.

• They take 22 months from planting to maturity.

• Crowns and slips are planted in the nurseries first before transplanting to the mai n seed bed.

iv) Suckers

• These are small plants that grow from the base of the main stem.

• They have adventitious roots which grow quickly when planted to form a new plant.

• They are used to propagate bananas, sisal, and pineapples.

• When planted, suckers give uneven growth leading to maturity at different times.

• They should be planted when they are young.

v) Tubers

• These are underground food storage organs which are short and thick.

• They are used as vegetative propagation materials because they s prout and produce roots for
growth.

• There are mainly two types of tubers, the stem and root tubers.

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 AGRICULTURE NOTES

• Root tubers develop from the thickening of the adventitious roots.

• Root tubers are not commonly used for propagation since they produce weak stems.

• A good example of a root tuber is the sweet potato.

• On the other hand stem tubers have some auxiliary buds which are sometimes referred to as
‘eyes’.

• These eyes sprout to produce stems which grow into plants. Stem tubers are therefore swollen
stems with scales leaves.

• A good example of a stem tuber is Irish potato.

vi) Vines.

• These are soft wood cuttings which produce roots easily upon planting to give rise to new
plants.

• They are cut from the mother plants and planted directly into the field.

• Soft wood cuttings (vines) are taken from rapidly growing shoots.

• The soft upper parts of the shoots are preferred.

• When preparing the cuttings, some leaves and nodes are included.

• Roots are produced from the nodes.

vii) Cuttings and setts

- Cuttings are portion of plants parts which are cut and then planted.

- They may be from stems, roots or leaves.

- A stem cutting must have a bud which develops into shoot.

- The root cutting must have an eye. Cutting must have an eye.

- Cuttings must produce leaves as soon as possible so that they can start making their own
food.

- Sometimes cuttings are induced to produce roots by use of rooting hormones.

- Once the cuttings have developed roots, they give rise to new plants.

- In some crops, the cuttings are big enough to be planted directly to the main seedbed whereas
there are some plants whose cuttings are first raised in special nurseries before they are
transplanted to the seedbed.

- The cuttings of Napier grass and sugar -cane are planted directly on the seedb ed but those of
tea; have to be raised in special nursery before they are transferred to the seed bed.

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 AGRICULTURE NOTES

- Examples of crops which are propagated by use of stem cuttings include: tea, cassava, and
sugar-cane and Napier grass.

- The stem cuttings used to propagate sugar-cane are known as ‘setts’. Setts are stem cuttings
which have 3-5 nodes are usually 30-45 cm long.

Factors affecting rooting of cuttings.

• Temperature: for the cuttings to produce roots warm temperatures are required around the
root zone while cool temperatures are important for the aerial part of the cuttings. For most
species optimum day and light temperatures for rooting are 22 -27°c and 15-21° c respectively.

a) Relative humidity: Proper rooting of cuttings requires high humidity which lowe r the
transpiration rate. It also increases and maintains leaf turgidity all the time.

As such, cuttings should be rooted in green houses or under shady conditions, where relative
humidity can be regulated. Sometimes the propagation area can be sprayed wit h water to keep
it moist.

b) Light intensity: soft wood cuttings need high intensity light to produce roots. This is
because light promotes the production of roots since it affects the rate of photosynthesis.

Hard wood cuttings do well in dark conditions s ince they have high amount of stored
carbohydrates and therefore rooting is excellent in darkness.

c) Oxygen supply: plentiful supply of oxygen is required for root formation. The rooting
medium used must therefore be capable of allowing proper aeration.

d) Chemical treatment: these rooting hormones which promote the production of roots in
cuttings. The common ones include IAA (Indoleacetic acid).

e) Leaf area: Soft woods cuttings require a lot of leaves for photosynthesis while hardwood
cuttings will produce roots better without leaves.

Selection of planting materials

When selecting materials for planting the following factors must be considered:

• Suitability to the ecological conditions – the selected planting materials should be well
adapted to the soil conditions, temperatures and amount of rainfall in the area.

There are many varieties of maize, for example, which are suitable to different ecological
conditions. Hybrid 622f or example is mainly for the high altitudes areas of Kenya 513 for the
medium altitudes and the Katumani composites for the low rainfall areas while the coast
composites are suitable for the coastal conditions each variety will grow well and produce high
yields if grown under the correct conditions

• Purity of the materials - planting materials should be pure and not mixed with other off
types the percentage purity of planting materials will affect the seed while higher seeds rates
are used for impure seeds.

• Germination percentage - This is a measure of the germination potential of s eeds it is

expressed as a percentage for example a germination percentage of 80 means that for every 10
seeds planted 80 of them are expected to germinate.

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 AGRICULTURE NOTES

Germination percentage helps to determine the seed rates of crops lower seed rates are used
for crops with higher germination percentage while higher seed rates are used for those with
lower germination percentage.

• Certified seeds - These are seeds which have been tested and proven to have 100
germination potential and free from diseases and pests they give high yields after the first
planting but the subsequent yields decline if replaced therefore in this case it is always
advisable to buy new seeds which are certified every time planting is done In Kenya certified
seeds are produced by the Kenya seed company (KSC) and distributed by Kenya Farmers
Association (KFA) and other agents.

Preparation of Planting Materials.

After the planting materials are selected they are prepared in different ways before they are
planted.

Some of the methods used to prepare planting materials include the following:

(a)Breaking the seed dormancy.

Some seeds undergo a dormancy period between maturity and the time they sprout. The
dormancy period is the stage whereby a seed cannot germinate, the stage of inhibited growth of
seed. It should be broken before the seed is planted.

Methods of breaking seed dormancy.

The following methods are used to break seed dormancy:

(I) Mechanical method:

This is a method which aims at scratching the seed coat to make it permeable to water.

Scarification is done by rubbing small sized seeds against hard surface such as sand paper,
while filling or nicking the seed coat with a knife is done to large sized seeds such as croton
seeds.

(ii) Heat treatment: this involves the use of hot water or burning the seeds lightly. It softens
the seed coat making it permeable to water and thus is able to germinate.

The seeds are soaked in hot water about 80’c for 3 -4 minutes after which the water is allowed
to drain off.

Example of seeds treated in this way includ e: leucean calliadra and acacia.

Light burning also serves the same purpose as hot water treatment.

In this case trash is spread over the seeds which are already covered with a thin layer of soil.

The trash is burned, after which the seeds are retrieved an d planted. Examples include acacia
and wattle tree seeds.

Overheating should be avoided as this will cook the seeds.

(iii)Chemical treatment: seeds are dipped in specific chemicals such as concentrated sulphuric
acid, for two minutes and then removed.

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 AGRICULTURE NOTES

The chemical wears off the seed coat making it permeable to water.

Care should be taken not to leave the seeds in the chemicals for too long as this will kill the
embryo.

Cotton seeds are normally treated with chemicals to remove the lint or fibres.

iv) Soaking in water: seeds are soaked in water for a period of between 24 – 48 hours until
they swell. They are then removed and planted immediately.

The seeds treated thus germinate very fast. Pre -germinated seeds are used when raising rice in
the nurseries.

b) Seed dressing

This is the coating of seeds with fungicides or an insecticide or a combination of the two
chemicals.

This is particularly common with cereals, sugar -cane and legumes.

The chemicals protect the seedlings from soil -borne diseases and pests.

Certified seeds which are sold by seed merchants in Kenya have been dressed with these
chemicals.

Farmers can also buy the chemicals and dress their own seeds.

C) Seed inoculation

In areas where soils are deficient in nitrogen, legumes such as beans, clovers a nd peas should
be coated with an inoculant.

An innoculant is a preparation which contains the right strain of Rhizobium depending on the
type of legume and encourages nodulation, hence nitrogen fixation.

Below is a table showing different legume crops and their right strain of Rhizobium.

When handling inoculated seeds, care should be taken to prevent them from coming in contact
with chemicals.

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 AGRICULTURE NOTES

This means that inoculated seeds should not be dressed with chemicals as these will kill the
bacterium.

They should also be planted when the soil is moist to avoid dehydration which kills the
bacterium.

d) Chitting

This practice is also referred to as sprouting.

The selected seed potatoes ‘setts’ which are used as planting materials are sprouted before
planting to break their dormancy.

The setts of about 3-6 cm in diameter are arranged in layers of 2 or 3 tubers deep in a partially
darkened room.

The setts should be arranged with the rose - end facing upwards and the heel-end downwards.

Diffused light encourages the pr oduction of short, green and healthy sprouts.

If Chitting is done in complete darkness, long, pale thin sprouts develop which break easily
during planting.

During Chitting potato aphids and tuber months should be controlled by dusting or spraying the
sett with dimethoate.

Sometimes a chemical known as Rendite is used to break dormancy, thus inducing sprouting.

Chitting is done mainly to make sure that growth commences immediately the seed is planted so
as to make maximum use of rains for high yields.

Time of planting

The timing of planting or sowing is influenced by the type of crop to be planted and the
environmental conditions of the area.

Factors to consider in timing planting.

• The rainfall pattern/moisture condition of the soil.

• Type of crop to be planted Soil type.

• Market demand.

• Prevalence of pests and diseases.

• Weed control.

Timely planting is necessary and should be done at the onset of rains. In some areas where
rainfall is scare dry planting is recommended.

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 AGRICULTURE NOTES

Advantages of timely planting.

• Crops make maximum use of rainfall and suitable soil temperature, leading to vigorous
growth.

• Crops usually escape serious pests and diseases attack.

• Crops benefit from nitrogen flush which is available at the beginning of the rain.

• For horticultural crops, proper timing ensures that the produce is marketed when prices are
high.

• Crops establish earlier than the weeds, hence smothering them.

Methods of planting.

There are two main methods of planting : -

• Broadcasting.

• Row planting.

Broadcasting.

This method involves scattering the seeds all over the field in a random manner.

It is commonly adapted for light tiny seeds such as those of pasture grasses.

It is easier, quicker and cheaper than row planting.

However, it uses more seeds than row plantin g and the seeds are spread unevenly leading to
crowding of plants in some places.

This results in poor performance due to competition.

Broadcasting gives a good ground cover, but weeding cannot be mechanized.

For good results, the seedbed should be weed -free, firm and have a fine tilth.

Row planting.

The seeds or other planting materials are placed in holes, drills or furrows in rows.

The distance between one row to the other and from one hole to the other is known.

In Kenya, both large and small – scale farmers practice row planting.

It is practiced when planting many types of crops, especially perennial, annual and root crops.

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 AGRICULTURE NOTES

Advantages of row planting.

• Machines can be used easily between the rows.

• It is easy to establish the correct plant population.

• Lower seed rate is used than if broadcasting is adopted.

• It is easy to carry out cultural practices such as weeding, spraying and harvesting.
Disadvantages of row planting.

• It does not provide an ample foliage cover. Thus the soil is liable to being eroded by wind and
water.

• It is more expensive than broadcasting because of consuming a lot of labour and time.

• It requires some skill in measuring the distances between and within the rows.

Seeds can also be planted by dibbling where the planting hol es are dug by use of pangas or
jembe, or by a dibbling stick (dibbler).

Most of the dibbling is done randomly although rows can also be used when using a planting
line.

Random dibbling is not popular in commercial farming due to low levels of production.

It is only common among conservative farmers in planting of legumes such as beans, pigeon
peas and cow peas.

Over-sowing.

This is the introduction of a pasture legume such as desmodium in an existing grass pasture.

Some form of growth suppression of existin g grass such as burning, slashing or hard grazing
plus slight soil disturbance is recommended before over sowing.

A heavy dose of superphosphate, preferably single supers at a rate of 200 -400 kg/ha is applied.

The grass must be kept short until the legume is fully established.

Regardless of the method of establishment, the pastures and fodder stands should be ready for
light grazing 4-5 months after planting if rainfall and soil fertility are not limiting.

Under-sowing.

This refers to the establishment of pasture under a cover crop, usually maize. Maize is planted
as recommended and weeded 2-3 weeks after the onset of rains.

Pasture seeds are then broadcasted with half the recommended basal fertilizer.

No further weeding should be done and maize should be ha rvested early to expose the young
pasture seedlings to sunlight.

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The benefits of under sowing include facilitating more intensive land utilization and encouraging
an early establishment of pastures.

Fodder crops and vegetetively propagated pasture species may also be under sown as long as
rainfall is adequate for their establishment.

Timing is not very crucial in this case and planting can be done as late as 6 -8 weeks after the
onset of rains.

Plant population

This refers to the ideal number of plants that can be comfortably accommodated in any given
area, without overcrowding or too few to waste space.

Agricultural research has arrived at the optimum number of various crop plants to be
recommended to farmers.

Plant population is determined by dividing the p lanting area by spacing of the crop.

This may be simplified thus:

Plant population = Area of land/ Pacing of crop

Example

Given that maize is planted at a spacing of 75 x25 cm, calculate the plant population in a plot of
land measuring 4x3 m.

Working

Area of land

Plant population = Pacing of crop

Area of land = 400cm x 300 cm

Spacing of maize = 75 cm x 25 cm

Therefore, plant population = 400 cm x 300 cm

75 cm x 25 cm

= 64 plants.

Spacing

It is the distance of plants between and within the rows. Correct spac ing for each crop has been
established as shown in table below.

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 AGRICULTURE NOTES

Spacing determines plant population and the main aim of correct spacing is to obtain maximum
number of plants per unit area which will make maximum use of environmental factors.

Wider spacing leads to a reduced plant population which means lower yields, whereas closer
spacing could lead to overcrowding of plants and competition for nutrients and other resources
would occur.

Correctly spaced crops produce yield of high quality that are accepta ble in the market.

Spacing is determined by the following factors:

• The type of machinery to be used.

The space between the rows should allow free passage of the machinery which can be used in
the field.

For example, the spacing between rows of coffee is supposed to allow movement of tractor
drawn implements.

• Soil fertility

A fertile soil can support high plant population. Therefore closer spacing is possible.

• The size of plant

Tall crop varieties require wider spacing while short varieties require clo ser spacing, for
example, Kitale hybrid maize is widely spaced than Katumani maize.

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• Moisture availability.

Areas with higher rainfall are capable of supporting a large number of plants hence closer
spacing than areas of low rainfall.

• Use of crop.

Crop grown for the supply of forage or silage material is planted at a closer spacing than for
grain production.

• Pest and diseases control.

When crops are properly spaced, pests might find it difficult to move from one place to the
other, for example, aphids in groundnuts.

• Growth habit.

Spreading and tillering crop varieties require wider spacing than erect type.

Seed rate.

Seed rate is the amount of seeds to be planted in a given unit area governed by ultimate crop
stand which is desired.

The objective of correct spacing of crop is to obtain the maximum yields from a unit area
without sacrificing quality.

Most crops are seeded at lighter rates under drier conditions than under wet or irrigated
conditions.

Seeds with low germination percentage are planted at higher rates than those which have about
100% germination percentage. There is an optimal seed rate for various crops.

For example, the seed rate for maize is 22 kg per hectare, wheat is 110 kg per hectare and
cotton is between 17 to 45 kg per hectare.

Factors to consider in choosing seed rates.

• Seed purity.

When planting seed which is pure or with a high germination percentage, less seed is required.
On the contrary, more seeds are required when using impure or mixed seeds.

• Germination percentage.

Less seed is used when its germination percentage is higher. Seed of lower germination
percentage is required in large amounts.

• Spacing.

At closer spacing, more seeds are used than in a wider spacing.

• Number of seeds per hole.

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 AGRICULTURE NOTES

When two or more seeds are planted per hole, higher seed rate is required than when only one
seed is planted per hole.

• The purpose of the crop.

A crop to be used for silage making is spaced more closely than one meant for grain production.

This would require use of more seeds. Maize to be used for silage making, for example, requires
more seeds than that meant for production of grain.

Depth of planting.

This is the distance from the soil surface to where the seed is placed. The correct depth of
planting is determined by:

• Soil type: seeds will emerge from grater depths in sandy soil that are lighter than in clay
soils.

• Soil moisture content: It is recommended that one plants deep in dry soils in order to place
the seeds in a zone with moist soil.

• Size of the seed: Larger seeds are planted deeper in the soil because they have enough food
reserves to make them shoot and emerge through the soil to the surface.

• Type of germination: seeds with epigeal type of germination (carry cotyledons above the
soil surface) such as beans, should be planted shallower than those with hypogeal type of
germination (leave cotyledons under the soil) such as maize.

Suggested Activities.

1. Learners to carry out planting using broadcasting method and planting rows.

2. Learners to identify different vegetative propagation materials displayed by the teacher.

3. Learners to determine the correct plant population for a given area by mathematical
calculations.

4. Learners to collect samples of different tree seeds and prepare them for planting by various
methods of breaking seed dormancy.

5. Learners to determine the germination percentage of different samples of cereals and legume
seeds.

Crop Production III

(Nursery Practices)

Introduction

• Planting materials are either planted directly in a seedbed or indire ctly through a nursery bed.

• A seedbed is a piece of land which could be small or large and prepared to receive planting
materials.

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• A nursery bed on the other hand is a small plot of land specially prepared for raising seedlings
or planting materials before transplanting.

• It is usually 1m wide and any convenient length depending on the quantity of seedlings to be
raised.

• A seedling bed is a special type of nursery bed used for raising seedlings pricked out from the
nursery bed due to overcrowding bef ore they are ready for transplanting.

• Pricking out refers to the removal of seedlings from a nursery bed to a seedling bed.

• Nursery practices refer to all the activities carried out throughout a nursery life to raise
seedlings.

Importance of Nursery Bed in Crop Production

• To facilitate the production of many seedlings in a small area.

• It is easy to carry out management practices in a nursery than in the seedbed.

• It facilitates the planting of small seeds which develop into strong seedlings that ar e easily
transplanted.

• It ensures transplanting of only healthy and vigorous growing seedlings.

• It reduces the period taken by the crop in the field.

• Excess seedlings from the nursery may be sold to earn income.

Selection of a Nursery Site

Factors to consider;

• Nearness to the water source.

• Type of soil.-should be well drained, deep and fertile, preferably loam soil.

• Topography.-it should be situated on a gentle slope to prevent flooding and erosion through
surface run-off.

• Previous cropping.-to avoid build up of pests and diseases associated with particular plant
families, consider the preceding crops.

• Security.-select a site that is protected from theft and destruction by animals.

• Protection against strong winds and heat of the sun. -select a sheltered place. i.e. to avoid
excessive evapo transpiration and uprooting seedlings.

Types of Nurseries

Categories of nurseries:

• Vegetable Nursery:

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- They are used for raising the seedlings of vegetable crops.

- Tomatoes, cabbages, kale, onions, brin jals and peppers.

• Vegetable Propagation Nurseries:

- They are used for inducing root production in cuttings before they are transplanted, - The
cuttings can be planted directly in the soil and hence called bare root nurseries.

- Or planted into containers such as pots, polythene bags and others, hence called containerized
nurseries.

• Tree Nurseries:

- These are used for raising tree seedlings.

- The seedlings can be raised in bare root nurseries or in containerized nurseries.

Nursery Management Practices:

• These are the practices carried out in the nursery while the planting materials are growing.

They include:

• Mulching. – light mulch should be applied on thenursery bed.It be should be removed on the
4th day

• Weed control.

• Shading.

• Pricking out.

• Pests and disease control.

• Hardening off

• Watering.

Preparation of vegetative materials for planting:

• Cuttings -These are plant parts such as stems, leaves and roots induced to produce roots and
used as planting materials.

• Grafting

- It is the practice of uniting two separate woody stems.

- The part bearing the roots is referred to as root stock while the part which is grafted onto the
rootstock is known as scion.

- The scion has buds which develop into the future plant.

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- The ability of the rootstock and the scion to form a successful union is termed as
compatibility.

Methods of Grafting

• Whip or tongue grafting:

- In this case the diameter of the rootstock and the scion are the same.

- It is carried out when the diameter of the scion and the roots tock is 'pencil' thick.

• Side grafting: In this case the diameter of the rootstock is bigger than that of the scion.

Other types of grafting include ;

• Approach grafting,

• Notch grafting

• Bark grafting. Budding:

• It is the practice of uniting a vegeta tive bud to a seedling of another plant.

• The scion has only one bud and some bark with or without wood.

• The bud is inserted in a slit made on the bark of the stock.

• It is held tightly on the stock by tying with a budding tape until it produces a shoo t.

Methods of Budding:

• T-budding

• Top budding

• Patch budding.

Importance of Budding and Grafting:

• Plants with desirable root characteristics but with undesirable products may be used to
produce desirable products for example lemon¬ -orange graft.

• They facilitate the changing of the top of the tree from being undesirable to desirable

• They make it possible to grow more than one type of fruit or flower on the same plant.

• They help to propagate clones that cannot be propagated in any other way. • The y help to
shorten the maturity period.

Layering

• It is the process by which a part of a plant is induced to produce roots while still attached to
the mother plant.

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 AGRICULTURE NOTES

• Once the roots have been produced, the stem is then cut off and planted.

Types of layering;

• Marcotting or aerial layering.

• Tip layering.

• Trench layering.

• Compound or serpentine.

Tissue Culture for Crop Propagation

• Tissue culture is a biotechnology used in cloning vegetatively propagated plants.

• It is based on the ability of plant t issue (or cells) to regenerate other parts of the plant.

• The tissues are derived from shoot tips where cells are undergoing rapid cell division and are
not differentiated.

• The cells are then provided with the right conditions which enable them to multi ply and
develop roots.

The Right Conditions for tissue culture:

• Culture medium.

• Correct temperature.

• Correct light intensity and

• Correct relative humidity.

Importance of Tissue Culture in Crop Propagation

• It is used to recover and establish pathogen-free plants especially in the control of viral
diseases.

• It is used in mass production of plantlets or propagules.

• It is fast and requires less space than the cultural methods of using cutting which requires a
bigger space.

Transplanting Seedlings

• Transplanting of vegetable and tree seedlings are generally the same.

• Generally, vegetable seedlings are ready for transplanting when they are one month old or
have 4 -6 leaves or are about 10-15cm in height.

• Before transplanting, the nursery bed is adequately watered 3 - 4 hours before lifting the
seedlings.

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 AGRICULTURE NOTES

• This ensures the seedlings are lifted easily with a ball of earth around the roots to minimize
root damage.

• Tree seedlings take a little longer to reach transplanting age compared to vegetabl e crop
seedlings.

• The roots are trimmed before lifting the seedlings.

• Transplanting should be done at the onset of the long rains to give the young trees a good
start.

• After transplanting the young trees should be protected from damage by animals for a period
of about one year.

Crop production IV (Field Practices I)

Introduction

• Field practices are activities carried out on the field to facilitate proper growth and maximum
yield of the various crops grown.

They include the following:

• Crop Rotation

• Mulching

• Routing field practices

• Crop protection

• Harvesting

Crop Rotation

• This is the growing of different types on the same piece of land in different seasons, in an
orderly sequence.

Importance of Crop Rotation

• Maximizes use of nutrients and moisture.

• Breaks the life cycle of pests and disease agents.

• Maintains good soil structure.

• Reduces soil erosion due to adequate soil cover.

• Controls weeds that are specific to certain crops e.g. striga on cereals .

• Improves soil fertility when legumes are included in crop rotation.

Factors Influencing Rotational Programme

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 AGRICULTURE NOTES

• Growth habits and nutrient req uirements.

• Liability to soil erosion.

• Crops attacked by the same pests and diseases should not follow one another in the
programme.

• Availability of capital and market for example beans or peas in legumes. Mulching

• This is the placement of materials such as banana leaves or polythene sheets on the ground
next to the growing crop.

• These materials should not come into contact with the base of the crop as they may encourage
pest attack.

Importance of Mulching

• Reduction of evaporation rate.

• Smothers weeds.

• Moderation of soil temperature.

• Reduction of speed of run offs.

Types of Mulching Materials

• Organic mulching materials such as;

- Sawdust, wood shavings, coffee pulps, rice husks,

- Dry grass, banana leaves, dry maize stalk, napier grass.

• Inorganic or synthetic materials commonly used are either black or transparent polythene
sheets.

Advantages of Mulching

• Prevents water evaporation thus maintaining moisture in the soil for crop use.

• Acts as an insulator thus modifying the soil temperature.

• It helps to control soil erosion.

• It controls weeds by suppressing them.

• After decomposition organic mulch add nutrients to the soil thus improving its fertility.

• Humus produced after the decomposition of organic mulch improves soil structure and the
water holding capacity of the soil.

Disadvantages of Mulching

• It is a fire risk.

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• Provides a breeding ground as well as a hiding pla ce for pests that finally may attack the
crops.

• Traps the light showers of rainfall thus lowering the chances of rain drops reaching the soil.

• It is expensive to acquire, transport and apply.

Routine Field Practices

Thinning

• Removal of excess, weak, damaged or diseased seedlings.

• Allows the remaining seedlings to get enough nutrients and moisture.

• It is aimed at obtaining optimum plant population.

Gapping

• Filling the gaps so as to maintain proper plant population.

• Gaps occur as a result of failure of seeds to germinate or dying of seedlings.

• It should be done early enough for the seedlings to catch up with the other plants.

Rogueing

• This is the removal and destruction of a diseased part of a plant or the whole plant.

• The destruction can be achieved through burning of the uprooted plant.

Pruning

• Removal of extra unwanted parts of the plant.

Reasons for pruning are:

• To remove old, unproductive or diseased, damaged parts of the plant.

• To train plants to take a desirable shape for exampl e formative pruning in tea.

• To control crop leave ratio hence avoiding overbearing.

• To control diseases and pests for example antestia bugs in coffee.

• To facilitate other operations such as spraying, picking and seeding.

• To reduce wastage of chemicals applied on the crop.

• To remove branches that interfere with traffic, telephone lines and view.

• Open up the plant to allow free air circulation and exposure of leaves to sunlight. Note: Tools
used are secateur, pruning saw and pruning knife.

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Earthing-up

• This is the placement of soil in form of a heap around the base of the plant.

• It is mostly carried out in tuber crops such as Irish and sweet potatoes to improve tuber
formation.

• It is also carried out in groundnuts and maize.

• In groundnuts it promotes production of pods while in maize it provides support to prevent

lodging.

Crop Protection

Weed Control

• Weeds are plants growing where they are not wanted, that is a plant out of place.

• Such plants include blackjack, couch grass, thorn apple a nd Mcdonald's eye.

• Such plants should be eradicated or controlled using recommended methods.

Pest Control

• Crop pests are living organisms that are harmful to the crops.

• They include; insects, nematodes, rodents, thrips and mites.

• They cause great damage to crops in the field and stored produce.

Control of Crop Diseases

• A disease is any alteration in the state of an organism and functions of a plant or its parts.

• Disease causing organisms are known as pathogens.

• They include fungi, viruses and bacteria.

• Diseases caused by fungi are referred to as fungal diseases while those caused by viruses and
bacteria are referred to as viral and bacterial respectively.

Harvesting

• It is the gathering or of the farm produce after maturity.

Time of harvesting depends on:

• Stage of maturity of the crops.

• Use of the crop.

• Tastes and preferences of consumers.

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• Weather conditions, hence liability to spoilage.

• Moisture.

Methods of harvesting is determined by:

• Scale of farming for example large scale far ming machines are used.

• Type of crop for example pyrethrum is harvested by hand.

• Uniformity in ripening of the crop for example wheat is harvested by use of combined
harvester while coffee is harvested by hand.

• Uniformity in height of the crop and size of seed, fruits and flowers.

• Financial status of the farmer.

• Part of the plant to be harvested.

Post-Harvest Practices

• These are the preparations carried out on crop produce before it gets to the consumer.

They include;

• Threshing/shelling.

• Drying.

• Cleaning.

• Sorting and grading.

• Dusting.

• Processing.

• Packaging.

Storage

Purpose of storage is to;

• Prevent spoilage

• Make the produce available for future use

• To await good market prices.

Requirements for proper store are:

• It should be clean.

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 AGRICULTURE NOTES

• It should be well ventilated.

• It should be raised from the ground to prevent damp conditions.

• It should be dry.

• It should be strong to hold crop produce.

• It should be easy to clean.

• It should be vermin-proof.

• It should be secure from t heft.

• It should be treated against pests such as weevils.

Types of Storage

• Traditional storage structures.

• Modern storage structures.

Preparation of the Store

• Cleaning the store.

• Maintenance

• Dusting the store with appropriate chemicals.

• Clearing the vegetation around the store to keep off vermin.

• Crop Production V: (Vegetables)

Introduction

• A vegetable is any crop that is grown and eaten fresh.

• Vegetables are important both for nutritional and commercial reasons.

• They are categorized on the basis of the part used as food.

• Such parts include;

- Leaves,

- Stems,

- Roots,

- Fruits,

- Flowers,

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 AGRICULTURE NOTES

- Pods

- Bulbs.

Vegetables are grouped into the following categories:

• Leaf vegetables for example kales and cabbages.

• Root vegetables for example carrots, beets, radishes and turnips.

• Fruit vegetables for example French beans and okra.

• Stem vegetables for example asparagus, leeks and spring onions.

• Bulb vegetables for example bulbed onions and garlic.

Tomatoes (Lycopersicon esculentum)

• Tomatoes are fruit vegetables widely grown in Kenya.

• The ripe fruit may be eaten raw cooked or processed to make tomato sauces, juices and
pastes.

Ecological Requirements

• Altitude: 0-2100m above sea level.

• Rainfall: 7S0-1300mm per annum.

• Soils: deep, fertile and well drained.

Varieties

• Fresh market varieties:

- Money maker,

- Marglobe, hundred fold,

- Beef eater,

- Hot set,

- Super marmande

- Ponderosa.

• Processing varieties:

- Kenya beauty,

- San -marzano,

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- Roma,

- Heinz 13S0,

- Primabel,

- Rutgers hybrid

- Cal- J. Nursery Practices

• Choose a site which has not been grown Solanaceae crop in the last three years.

• Nursery beds are raised about 15cm above the ground level.

• Make drills of 20cm apart and 1cm deep drill and cover the seeds.

• Provide shade or mulch material.

• Water twice a day.

• Apply phosphatic fertilizers during planting.

Seedbed Preparation

• The land should be dug deeply to control weeds.

Transplanting

• Seedlings are ready for transplanting when they are 10 -15cmhigh after about one month.

• Holes are made at a spacing of 60cm x 90cm.

• Apply 20gm of DSP in the planting hole.

• Transplant with a ball of soil around the roots.

• Apply mulch around each seedling.

• Transplanting is normally in the evening or on a cloudy day.

Field Maintenance

• Early control of weeds is necessary.

• Top dressing is done after crop establishes.

• Pruning and staking are done to train the plants to grow vertically.

Pests Controls

• American Bollworm

- Nature of damage: boring holes on the fruits.

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- Control: spraying insecticides.

• Tobacco White Fly

- Nature of damage: suck plant sap from the underside of the leaf, hence may transmit viral
diseases.

- Control: Destroy infected plant and spray insecticides.

Disease Control

• Late Blight

- Cause: Fungus

- Symptoms: dry patches on the leaves and fruits.

- Control: use of fungicides, crop rotation and destruction of affected materials.

• Blossom-end Rot

Caused by;

- Too much nitrogen in early stages.

- Irregular or infrequent watering.

- Calcium deficiency.

- Control: Apply calcium ammonium nitrate and correction of the above problems.

Harvesting

• For canning, fruits should be fully ripe.

• For fresh market, fruits should be partially ripe and packed in crates to avoid damage.

• The fruits should be graded according to;

- Size,

- Colour,

- Ripeness

- Freedom from blemishes.

Cabbage

• It is a leaf vegetable related to other brassica crops such as kales, cauliflower, Chinese
cabbage and Brussels sprouts.

• Cabbage leaves may be eaten raw in salads, steamed, boiled or cooked in a variety of ways.

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• The leaves can also be fed to livestock.

Ecological Requirements

• Altitude:

- Those with small heads: 900-1500m above sea level

- Those with Large heads: 1800-2700m above sea level.

• Temperature: require cool cond ition.

• Rainfall:

- 750-2000mm per annum.

- Should be well distributed throughout the growing period.

• Soils:

- Deep,

- Fertile

- Well drained.

Varieties

• Early maturing:

- Brunswick,

- Sugar loaf,

- Early jersey,

- Copenhagen market,

- Chinese cabbage,

- Celery cabbage,

- Cafe splits kool

- Gloria, mukuki,

- Golden acre .

• Late maturing:

- Drumhead,

- Savoy,

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- Perfection,

- Winningstadt.

Nursery Practices

• The beds should be raised, dimension 1 m wide and any convenient length (usually 2 -3m in
length).

• Make drills of 15-20cm apart.

• Sow seeds by drilling and cover to a depth of 1 cm.

• Provide shade or mulch material.

• Apply phosphatic fertilizers and mix thoroughly with soil during planting.

• Water twice a day.

Seedbed Preparation

• Cultivation should be done during the dry season so that all the weeds are killed.

• Dig holes at the spacing of 60cm x 60cm.

• Incorporate farm yard manure in the soil.

Transplanting

• Water the seedlings before uprooting.

• Seedlings are ready for transplanting after one month that is when they are 1O -15cm in
height.

• Select healthy and vigorous seedlings.

• Transplant the seedlings with balls of soil to prevent root damage.

• Plant to the same depth as they were in the nursery.

Field Maintenance

• Apply fertilizers during planting and top dress later.

• Control weeds to reduce competition.

Pest Control

• Diamond Black Moth

- Damage: Eats the underside of the leaf making windows or holes in the leaf.

- Control: Spray recommended insecticides.

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• Cutworms

- Damage: Attacks the stem at the ground level causing he plant to fall.

- Control: Spray recommended insecticides.

Disease Control

• Black Rot

- Cause: Bacteria

- Symptoms: Leaves turn yellow and rotting of the stem giving an offensive odour,

- Control: Closed season, crop rotation, use certified seeds and spray appropriate chemicals.

• Black Leg

- Cause: Fungus

- Symptoms: Brown to black spots on seedlings and dark canker on the stem.

- Control: crop rotation, destroy infected materials.

Harvesting

• Cabbages are ready for harvesting 3-4 months after transplanting.

• The heads are cut when they are solid and compact.

• Harvested cabbages are sold immediately.

Carrots (Daucus carota)

• It is a root vegetable grown in the cool areas of Kenya.

• It is commonly eaten raw in salads but can also be cooked.

Ecological Requirements

• Altitude: 0-2,900m above sea level.

• Rainfall:

- 750 - 1,000mm.

- Well distributed throughout the growing period.

• Soils:

- It requires deep,

- Fine tilth

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- Well drained soils that are free from o bstacles to allow for root expansion.

• Temperatures: it requires cool to warm temperatures as very high temperatures result in the
production of pale and short roots.

Varieties

• Fresh market varieties for example Chantenay and Nantes.

• Canning varieties for example Nantes .

• Fodder varieties for example Oxhast.

Land Preparation

• The field should be well dug to a depth of about 20cm.

• The soil clods should be broken to give a fine tilth before planting.

• Manure should not be applied as it induces fork ing which reduces the crop quality.

Planting

• Carrots are planted directly into the main seedbed.

• Seeds are drilled into rows made 20 -30cm apart.

• The seeds are then covered lightly and the soil pressed down.

• 90kg/ha of DSP should be applied at plant ing time in the drills.

• It should be mixed well with the soils before placing the seeds.

Field Practice

• Thinning - it is done 2 weeks after germination.

• Weed control- the field should be kept weed free.

• Earthing up should be done while weeding to e ncourage root expansion .

• Topdressing: after weeding 60kg of nitrogen per hectare should be applied as top dress.

• Irrigation - this should be carried out where or when there is not enough rainfall.

Pest Control

• Carrots do not have many field pests except the green aphids.

• These can be controlled by use of the appropriate pesticides.

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Disease Control

• Occasionally attached by the mildews especially in wet and humid environment.

• Thinning can be done to reduce humid conditions.

Harvesting and Marketing

• Carrots are ready for harvesting 3 -5 months after planting depending on the variety.

• They are lifted from the soil and sold fresh or canned.

Onions (Allium cepa)

• Onions are bulb vegetables grown in the warm areas of Kenya.

• They are used as a vegetable in salads and for flavouring foods, soups and stews.

Ecological Requirements

• Altitude: 0-2, 100m above sea level.

• Rainfall:

- 1,000mm of rain per year

- Irrigation in dry areas .

• Soils:

- Requires well drained fertile soils

- pH of 6.0 - 7.0 .

• Temperatures:

- Onions are a warm climate crops.

- However, some varieties prefer cool conditions.

• They require a fairly long dry period for ripening.

Varieties

• Red creole,

• Tropicana hybrid

• White creole.

Land Preparation

• The land should be well prepared leaving a fine tilth.

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• Farm yard manure at 40 - 50 tonnes per hectare should be applied and mixed well with the
soil.

Planting

• Direct: Seeds are drilled in rows 30cm apart and 8cm within the rows. 20kg/ha of DSP
fertilizer is used.

• Indirect: Seeds are established in the nurseries before transplanting them in rows 30cm
apart and 8 cm within the rows.

• Shallow planting is recommended for bulb expansion.

Field Management Practices

Thinning

• It is carried out only in the crop that has been dir ectly planted so as to achieve spacing of
8cm between two plants within the row.

• The thinned plants referred to as spring onions are used as vegetables in salads. Topdressing

• Calcium ammonium nitrate at the rate of 250kg per hectare is recommended for topdressing
onions.

• This is done 3 months after planting.

Pest Control

Onion Thrips:

• These cause silvering and withering of leaves from the tips downwards.

• They are controlled by spraying with appropriate insecticides such as Diazinon or fenthion.

Disease Control

Purple Blotch and Downey Mildew

• Purple blotch;

- Characterized by oval greyish lesions with purple centres on leaves.

- This causes leaf curling and die back.

• Downey mildew;

- Characterized by brown spores covering the leaves leading to d eath of the whole plant.

- The two diseases are effectively controlled by crop rotation and application of appropriate
fungicides.

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Harvesting and Marketing

• Onions are ready for harvesting 5 months after planting.

• When leaves start drying the tops are broken or bent at the neck.

• This hastens the withering of the stems.

• The bulbs are then dug out and left to dry in a shade for a few days.

• Onions are graded according to size and marketed in nets of about 14 -16kgs.

Livestock Health I

(Introduction to Livestock Health)

Introduction

• Health is the state of the body in which all the organs and systems are normal and functioning
normally.

• Disease is any deviation from the normal health of the animal.

Importance of Keeping Livestock Healthy:

• Healthy animals give high income due to low treatment costs.

• The productive life span of a healthy animal is longer.

• High production.

• Healthy animals can multiply regularly.

• Healthy animals give high quality products for example eggs.

• Safety of consumers of livestock products.

Predisposing Factors to Livestock Diseases

• These are conditions within or around the animal that make it easy for an animal to contract a
disease.

They include:

• Animal factors such as;

- species,

- breed,

- age,

- sex

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- colour of the animal.

• Environmental factors such as;

- chilling,

- being rained on,

- exposure to hot sun

- dampness.

• Management factors such as;

- poor feeding,

- housing,

- handling

- hygiene,

- overcrowding .

Signs of ILL-Health in Livestock

• Abnormal behaviour for example separation from the rest of the herd and restlessness.

• Abnormal posture for example limping and lameness.

• Alimentary canal disfunction such as blood stained faeces and abnormal defecation, diarrhoea
and dysentery.

• Urination: high frequency or too low and having strange colour.

• Skin: rough with scaly skin, blisters on the skin and hair loss.

Causes of Diseases

• Pathogenic causes ;

- viruses,

- rickettsia,

- protozoa

- fungi.

• Physical causes;

- fractures,

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- dislocation,

- sprains .

• Nutritional disorders for example milk fever.

• Chemical causes for example poisoning by agrochemicals.

Categories of Diseases

• Notifiable diseases ;

- These are diseases which cause high economic losses.

- Any case should be reported to the Chiefs, D. O.s, veterinary officers or the police.

• Tick-borne diseases - Transmitted by ticks.

• Breeding diseases - Transmitted through mating.

• Nutritional diseases for example milk fever and bloat.

• Parasitic diseases for example ascariosis.

General Methods of Disease Control

• Quarantine.

• Vaccination.

• Control of vectors by use of acaricides and rotational grazing.

• Disinfecting the equipment and buildings.

• Use of preventive drugs.

• Proper feeding of livestock.

• Culling of the animals which are carrier s/slaughtering the affected animals.

• Use of artificial insemination to control breeding diseases.

• Proper selection and breeding of animals.

• Proper housing and hygiene,

• Isolating sick animals.

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Appropriate Methods of Handling Livestock

Animals are handled for the following reasons:

• When inspecting the animal to ascertain any abnormality or signs of diseases.

• When administering any form of treatment such as drenching, injection and mastitis control.

• When spraying or hand dressing the animal with chemicals to control external parasites.

• When milking the animal.

• When performing some of the management practices such as dehorning, disbudding,

castration, hoof trimming .

When carrying out these activities animals should be restrained in a crush.

Other methods of restraining animals include the use of;

• halters,

• ropes,

• bull ring

• lead stick.

Livestock Health II (Parasites)

Introduction

• A parasite is an organism which obtains its livelihood from another organism (host) which
suffers damage.

• Parasitism is the association between a parasite and a host.

The effects of parasite on the host animal are:

• Depriving the host of its food.

• Sucking blood.

• Damaging the organs of the host.

• Cause irritation on the skin of the host.

• Destruction of hides and skins.

• Transmission of diseases.

• Cause obstruction in body passages.

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General Symptoms of Parasites Infestation:

• Emaciation.

• Pot bellied condition.

• Swellings in the jaw or other areas.

• Rough hair or rough coat.

• Anaemia.

• Diarrhoea.

• Presence of worm segments and blood stains in the defecation.

Types of Parasites

There are two types of parasites:

• External (ecto-parasites)

• Internal (endo-parasites)

External parasites are;

• ticks,

• tsetse flies,

• mites,

• lice,

• fleas

• keds

Life Cycle of ticks

• Eggs are laid in cracks on the ground.

• They hatch in 4-6 weeks into larvae which climb on the grass waiting for a passing animal.

One-Host Tick

• This requires one host to complete its life cycle.

• Example: blue tick (Boophilus decoloratus).

• Preferred sites: face, neck, dewlap and side of the body.

• Disease transmitted: Redwater and anaplasmosis.

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Two-Host Tick

• This requires two different hosts to complete its life cycle.

• Example: The red legged tick (Rhipicephalus everts)

• Preferred sites: Ears, anus, udder and the tail.

• Disease transmitted: Redwater and east coast fever.

• Example: Bont legged tick (amblyomma spp.)

• Preferred sites: Udder, scrotum and tail switch.

• Disease transmitted: Sweating sickness.

Three-Host Tick

• This requires three hosts to complete its life cycle.

• Example: The brown ear tick (Rhipicephalus appendiculatus)

• Preferred sites: Ears, tail switch and around the eyes.

• Disease transmitted: East coast fever and redwater.

• Bont tick transmit heartwater (amblyomma spp.)

Control of Ticks

• Dipping/spraying/hand dressing with acaricides.

• Rotational grazing.

• Ploughing the land to break the life cycle.

• Hand picking and killing.

• Fencing of the grazing fields to keep off other animals including wild game.

• Burning of grass to kill them in various stages.

Endo-parasites (internal Parasites)

• Endoparasites are helminths.

They can be divided into:

• Platyhelminthes/flatworms which include;

- Trematodes (flukes)

- Cestodes (tapeworms).

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• Nemato-helminthes/nematodes. E.g Roundworms.

General Symptoms of Helminthiasis

• Diarrhoea which foul the anal and tail region.

• Dullness.

• Anaemia.

• Big stomach (pot bellied condition).

• Presence of worm segments in faeces.

• Coughing.

Trematodes (Liver Fluke)

• There are two species of flukes:

- Fasciola gigantica

- Fasciola hepatica.

• Fasciola hepatica is more common.

• It is commonly found in the liver and bile duct of cattle, sheep and goats.

• Liver fluke is a problem in marshy and low lying wet areas.

Life Cycle of the Liver Fluke

• Adult fluke in the liver of the primary host lays eggs.

• Eggs pass through the bile duct into the small intestines and are passed out in faeces onto the
pasture.

• Under moist conditions, they hatch into a miracidium larva which sw ims about in search of a
secondary host (fresh water snails).

• In the snail, it develops through sporocyst, redia and cercaria.

• When it leaves the snail, the cercaria gets encysted on vegetation and becomes metacercaria.

• This is swallowed by the prima ry host with grass.

• The young fluke migrates into the liver through blood vessels when it matures.

Control of Liver Fluke

• Keep livestock off marshy areas near the rivers/streams/lakes and dams.

• Drench affected animals.

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• Drainage of swampy areas.

• Eradicate the intermediate host by use of molluscicides.

• Provide water to livestock in elevated troughs.

Tapeworms

• There are many species of tapeworms

Example;

• Taenia solium

• Taenia saginata.

The adults live in the small intestines of man (the primar y host).

• The intermediate host of Taenia solium is pig .

• The intermediate host of Taenia saginata is cattle.

Life Cycle of Tapeworm

• Adult tapeworms live in man's intestines where it lays eggs.

• Eggs are passed out with faeces,

• Then they develop an outer covering known as onchosphere.

• The eggs are swallowed by intermediate host.

• The outer covering is digested and the young worm emerges.

• This bores into the blood vessels and is carried to specific muscles such as the tongue, heart,
thigh muscles.

• It develops into an encysted form called bladder -worm.

• When the animal is killed and meat is eaten raw or in an inadequately cooked form, man gets
infected by the bladder¬-worm.

• In man, the bladder-worm evaginates and attaches itself onto the inte stinal wall where it
develops into an adult.

Control of Tapeworms

• Meat should be well cooked before eating.

• Use of drugs in primary host.

• Meat inspection by meat inspectors/ veterinary officers.

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• Use of pit latrines by man.

Nematodes (Roundworms)

Common ones are;

• Ascaris suum (pig roundworms),

• Ascaris lumbricoides found in man and sheep

• Haemonchus contortus found in sheep, cattle and goats.

• Roundworms are common in warm areas especially in areas where the standards of hygiene
and sanitation are low.

Nature of Damage

• Damage is done to the liver and lung tissues as they migrate in the body.

• Suck out blood.

• Deprive the host of food.

Control of Roundworms

• Use of drugs.

• Rotational grazing.

• Use of proper stocking rates to avoid overgrazi ng.

• Practicing high standards of cleanliness and hygiene such as use of latrines.

Livestock Production II (Nutrition)

Introduction

• Animals are fed for the purpose of production and body maintenance.

• The edible material given to animals is called food .

• It is digested, absorbed and

• utilized in the body.

• Nutrients are organic and inorganic substances contained in the food materials.

Components of Food material

• water,

• protein,

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• carbohydrates,

• fats and oils,

• vitamins

• mineral salts.

Water

Sources

• Free water (through drinking)

• Bound water (contained in feeds).

• Metabolic water (obtained from oxidation of food).

Functions

• Regulates body temperature.

• Transport agent in the body.

• Universal solvent in the body.

• Gives shape to the cells (turgidity).

• Acts as a lubricant.

• Acts as constituent of body fluids.

Factors Determining the Requirements of Water by Livestock

• Production level.

• Amount of dry matter eaten.

• Temperature of the surrounding area.

• Type of animal.

• Type of food eaten.

Protein

Sources:

• Groundnut cakes,

• cotton seed cakes,

• fish meal,

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• meat meal.

Functions:

• Growth of new tissues.

• Repair of worn out tissues (body building).

• Synthesis of antibodies.

• Synthesis of hormones and enzymes.

• Production of energy during starvation.

Digestion of Proteins

In non-ruminants, protein digestion takes placed in the stomach.

• Food is subjected to mechanical breakdown through chewing into small particles.

• Protein is acted on by enzymes to turn into amino acid which is assimilated into the
bloodstream.

In ruminants, protein digestion initially takes place in the rumen.

• Food is acted on by micro-organisms into microbial protein.

• Later, enzymatic action takes place in the "true stomach" or abomasum where proteins ar e
broken down into amino acids which are then assimilated into the bloodstream.

Carbohydrates

Sources:

• Cereals

• tubers

• commercially mixed feeds.

Functions:

• Supply energy and heat to the body.

• Excess is stored in form of fat for insulation of the b ody.

Digestion of Carbohydrates

• In non-ruminants;

- carbohydrate feeds are broken down by chewing into small particles.

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- Then enzymatic action further breaks down carbohydrates into glucose, fructose and galactose
which are then assimilated into the blo odstream.

• In ruminants;

- mechanical breakdown of carbohydrate feeds is followed by microbial activities which break

down cellulose into volatile fatty acids.

- These are absorbed through the rumen walls.

- Some carbohydrates are broken down by enzymatic action in the "true stomach" or
abomasum.

Fats and Oils

Sources:

• Cotton seeds,

• soya beans

• groundnuts.

Functions:

• Supply energy and heat to the body.

• Excess is stored as fat adipose tissues.

• Source of metabolic water in the body.

• Required for the development of neural system.

• Insulator in the body.

Digestion of lipids in Ruminants

• Fats are hydrolysed in the rumen into fatty acids and glycerol.

• Others are fermented into propionic acid,

• The shorter chains are passed to the true stomach w here enzymatic action takes place.

Vitamins

Sources:

• Green materials,

• dried grass

• fish liver oil.

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Functions:

• Protects the body against diseases.

• Regulate the functions of all parts of the body.

• It acts as a co-enzyme in the body.

Examples:

• Vitamin A,

• vitamin B2

• vitamin C,

• vitamin E

• vitamin K.

Minerals

Sources:

• Salt licks,

• bone meal,

• legumes

• cereals.

Functions:

• Form part of the tissues such as bones and teeth.

• Work together with the enzymes.

• Act as acid -base balances.

• Act as electrolyte in the body.

• Regulate osmotic balance in the body.

Examples:

• Calcium,

• phosphorus,

• magnesium,

• iron,

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• iodine,

• sodium

• chlorine.

- Calcium and phosphorus -

• Needed for teeth and bone formation.

• Lack of these minerals leads t o rickets, osteomalacia.

- Lack of iron leads to anaemia.

Classification of Animal Feeds

This is based on nutrient composition:

• Roughages.

• Concentrates.

• Feed additives.

Roughages

• Are feeds of low available nutrients per unit weight and high fibre c ontent.

Examples:

• Dry roughages,

• succulent roughages,

• residues from agricultural by products and conserved materials.

Characteristics

• Low level of available nutrients.

• Have high level of calcium especially legumes.

• Good source of vitamin A.

• Have high fibre content.

Concentrates

• Are feeds of high available nutrients per unit weight.

Examples:

• Maize germ and bran,

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• malt extract,

• milk products,

• soyabeans,

• oil seed cakes,

• meat meal,

• bonemeal

• bloodmeal.

Characteristics

• Low fibre content.

• Feed content is consistently high.

• High digestibility of the feed.

• High in nutrient content.

Feed Additives

These are substances added to the feed to increase;

• palatability,

• medication

• or hormones to make animals produce more.

There are two types:

• Nutritive additives, such as mineral licks (maclick).

• Non-nutritives additives, such as;

- medicants (coccidiostats),

- Stilboestrol (used in beef animals)

- oxytocin (to increase milk let down).

Functions

• Stimulate growth and production.

• Improve feed efficiency.

• Prevent disease causing organisms.

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Compounded Feeds

• These are the feeds prepared and mixed by use of machines.

• These feeds can be round, pelleted, pencils, cubes or mash.

Poultry feeds can be categorized as:

• Chick mash having 20% D.C.P. given to chicks.

• Growers mash having 16% D.C.P. given to growers.

• Layers mash having 12-15% D.C.P. given to layers.

Meaning of terms used to express feed values

• Nutritive ratio (NR):

- Is the proportion of protein to carbohydrates a nd fats.

- In young animals 1:3:6

- In old animals 1:8.

• Crude protein (C.P): Is the total amount of protein contained in a feed.

• Digestible Crude Protein (D.C.P): Is the portion of crude protein which an animal is capable of
digesting.

• Crude Fibre (C.F.):

- Is the total amount of fibre contained in a feed.

- It is mainly lignin and cellulose.

• Digestible Fibre (D.F.): Is the portion of the total fibre contained in a feed which an animal is
capable of digesting.

• Dry Matter (D.M.): Is the material left in a feed after water has been removed.

• Starch equivalent (S.E.): Is the amount of pure starch which has the same energy as 100kg of
that feed.

• Total Digestible Nutrients (T.D.N.): Is the sum of all the digestible organic nutrients such as
fats, proteins, carbohydrates and fibre.

Computation of Livestock Rations

• Ration:

- Is the amount of food that will provide essential nutrients to an animal in a 24 hour period

- to enable that animal to meet its maintenance and production requirements.

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• Balanced ration:

- Is the ration that contains all the essential nutrients in required amounts and in the right
proportion.

• Maintenance ration:

- is the portion of a feed required by an animal to continue with the vital body processes with
no loss or gain in weight.

• Production ration:

- Is the feed required by animals over and above maintenance ration to enable the animal to
produce;

- for example; milk, eggs, wool, grow in size, perform work, reproduce and fatten.

Steps in ration formulation

• Finding out the animal's feed requirement based on body weight.

• List all the available feeds, with their nutrient composition and their prices.

• Calculate the amount of ingredients required in the ration to meet the animals needs.

Methods used in ration formulation

• Trial and error method

• Pearson’s square method

• Graphical method

• Linear programming(use of computers)

Examples;

Mix a Pigs ration 22% protein using soya bean meal 40% DCP and maize meal containing
8%DCP.

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Digestion and digestive systems

• Digestion is the process through which food is broken down into small particles in the
alimentary canal ready for absorption into the blood stream.

Digestion of food in livestock takes place in three stages;

• Mechanical breakdown and chewing

• Microbial breakdown by bacteria and protozoa in the rumen of ruminants

• Chemical breakdown by enzymes.

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Rumen

• Breakdown of food by micro -organisms and also stores food.

• Synthesis of vitamin B-complex.

• Synthesis of amino acids from ammonia gas.

• Proteins are broken to peptides and amino acids.

• Carbohydrates are broken to volatile fatty acids.

Reticulum:

• Separates large food particles from the small particles.

• Retains foreign materials such as stones, hard wood and sand.

Omasum:

• Breaks up food by grinding.

• Reduction of water content from the feed stuff.

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Abomasum:

• Enzymatic digestion takes place here .

• Contains some microbes which digest cellulose.

• Breaks up food by grinding.

• It is also found in non¬-ruminants.

Comparison Between Digestion in Ruminant an d Non-ruminants

Differences

Ruminants

1. Chew the cud

2. Have four stomach chamber thus polygastric

3. Regurgitate food

4. Can digest cellulose except have micro -organisms in the rumen that digest cellulose

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5. Have no Ptyalin in the saliva hence no enzymat ic digestion in the mouth Most digestion and
absorption takes place in the rumen.

6. The alkaline saliva due to presence of ammonia.

Non -ruminants

1. Do not chew the cud

2. Have one stomach chamber thus monogastric

3. Cannot regurgitate food once swallowe d

4. Have no micro-organisms in the stomach hence cannot digest cellulose except those that
have micro-organisms in the caecum

5. Have Ptyalin in the saliva hence enzymatic digestion starts in the mouth digestion and
absorption takes place in the small int estines.

6. The saliva is neutral pH.

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Functions of the Parts of Poultry

• Crop:

- Storage of food.

- Softening of food by secretions from small glands in the walls.

• Proventriculus: Enzymes start the breakdown of food.

• Gizzard:-Crushes and grinds the coarse food (has small grit and gravel).

Comparison Between Digestion In Ruminants and Non -Ruminants

Similarities Between Digestion In Ruminants and Non -Ruminants

• Digestion in young ruminants is similar to that in non -ruminants as they do not have a
developed rumen-reticulum complex.

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• Final protein digestion takes place in the small intestines in both cases.

• Water absorption takes place in the colon in both ruminants and non¬ ruminants

Livestock Production III

(Selection and Breeding)

Introduction

 The breeding of animals is under human control, and the breeders decide which individuals
shall produce the next generation.
 The breeder makes a choice.
 The breeding of animals is based upon the fact that certain qualities are genetic ,hence
valuable qualities are passed on from parents to off -springs.
 The qualities can be maintained or improved in the next generation.

The performance of an animal is influenced by two major factors;

 Genetic potential
 The environment, which includes:

◦ Feeding,

◦ Health,

◦ Care

◦ The ecological conditions.

 The genetic potential of an animal is inherited from its parents.

 In selection and breeding animals with superior characteristics are selected and allowed to
mate.
 In the process they transmit the superior characteristics to their offspring.
 When this is done over a long period of time, it results in livestock improvement.

Reproduction and Reproductive Systems

 Reproduction is the process by which off-springs are produced.

 All farm animals multiply by means of sexual reproduction.
 It begins with fertilization which is the fusion of male and female gametes to form a zygote.
 Fertilization takes place internally in the body of the female.
 The embryo(zygote) formed develops inside body of mother, fed and protected until end of
gestation period.
 In poultry, the process is different in that eggs are fertilized internally but laid and
development of the chick takes place outside during incubation.

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 AGRICULTURE NOTES

 In both male and female, certain organs are specialized for the process of reproduction.
 Some of these organs secret fluids which are necessary for the movement and survival of the
gametes(reproductive cells.)

Reproduction in Cattle

 The male reproductive organs produce the male gametes,the spermatozoans.

 These are introduced into female reproductive system, where they fuse with the sperm to form
zygote.

Reproductive system of a bull

 The testis:

> There are two testes hanging loosely between hind legs.

> Enclosed by loose skin (scrotum)scrotum regulate temperature of testis for optimum
production of sperms.

> Produce spermatozoa(sperms)which are stored in coiled tube called epididymis

 Epididymis: Storage of spermatozoa.

 Sperm ducts:

> Conveys sperm from the testis and urine through the penis.

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 AGRICULTURE NOTES

> sphincter muscles contract to allow each to pass separetly.

 Seminal vesicles produce fluid called semem.

 semen carries sperms out of penis in fluid form.
 Prostate gland -produce fluid that neutralize the acidic effects of urine in the urethra
preventing death of sperms.
 Accessory glands: Include seminal vesicles cowpers gland and prostate gland.
 Urethra: Conveys urine and semen.
 Penis:

> Surrounded by a sheath which is an extension of skin.

> It introduces sperms into the vagina of a cow through the vulva during mating

> It is a copulatory organ, also used for urination.

Reproductive system of a cow

Ovaries and fallopian tubes(oviduct)

 Two ovaries located in abdomen, left and right.

 Produce ova/e%gs and hormones which control sexual cycle.
 Oestrogen produced by graafian follicle inside ovary induces oestrus ie. Heat period so that the
cow shows signs of heat
 After every 21 days the ovary releases a mature ovum and the cow comes on heat.
 The ovum travels through the fallopian tubes to the uterus.

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 AGRICULTURE NOTES

 The release and movement of the ovum down to the uterus is called ovulation.
 If mating is done at this time, fertilization will take place.
 The fertilized egg implants itself onto the endometrium(walls of uterus)and develops into
foetus.

Fallopian tubes:

 Fertilization takes place here.

 Also a passage for the egg from the ovary to the uterus.

The uterus:

 Embryo develops here.

The cervix: Closes the uterus.

The vagina and Vulva:

 Vulva is the external opening of female reproductive system.

 It allows mating to take place so that sperms are deposited into the vagina.
 The foetus and urine are removed through the vulva.

Pregnancy

 Is period between fertilization of ova and the expulsion of the foetus through the vulva.
 Also called gestation period.
 In cattle gestation period is 270-285 days.
 Ends with the birth of a calf.
 The reproductive tract undergoes a period of rest during which it is repaired and returns to
normal.
 During pregnancy, hormone called progesterone is produced by the placenta to maintain the
foetus in the uterus.

Parturition(giving birth)

 Act of giving birth called parturition.

 This time the foetus expelled through the birth canal.

When an animal is about to give birth, it shows sign;

> Distended udder which produces thick milky fluid called colostrums.

> Swollen vulva producing thick mucus.

> Loose and slackened pelvic girdle.

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 AGRICULTURE NOTES

> Visible pin bones.

> General restlessness.

 Animal parturates within 2-3 hours after this signs.

 The correct presentation is with the front feet first ,and the head outstretched and resting in
between the fee.
 Any other presentation called mal-presentation or breech presentation and requires assistance.

Reproduction in Poultry

 The cock has no penis but a small opening near the vent through which sperms are emitted.
 Cock has testes within the body.
 The hen has elongated oviduct for formation of an egg.
 Fertilization occurs internally.
 During mating the cloaca of the hen and the vent of the cock fit into each other and then semen
is poured into the cloaca ,then sucked to the oviducts.

The Reproductive System of a Hen

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 AGRICULTURE NOTES

Ovary

 Hen has two ovaries but one functional.

 Ova formed in ovaries.
 3500-4000 ova present inside ovary held by follicle.
 Mature ovum released
 via rapture of follicle.
 It moves into oviduct received by the funnel.

Funnel(infundibulum)

 Fertilization occurs here.

 Chalazae also added to yolk.
 Time here is 15 minutes.
 It is 11.6cm long.

Magnum

 Thick albumen is added.

 Stays for 3hrs.its 33cm

Isthmus

 Its 10.6cm long.

 Shell membranes added.
 Determines shape of egg.
 Water, mineral salts and vitamins added.
 Takes 15 minutes.

Uterus(shell gland)

 Calcium deposited 9ie.

 Pigments added.
 shell added around the egg.
 Addition of albumin finished.
 Stays here for 18-22hours.

Vagina

 Short, 6.9cm long.

 For temporal storage of egg before laying

Cloaca

 Egg moves out of cloaca through the vent.

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 AGRICULTURE NOTES

 The cloaca extents out to prevent the egg from breaking.

NB;

 Egg formation not depended on fertilization.

 Egg formation takes 24-26hours.
 The components of egg are obtained from body reserves of the hens body.

Selection of a Breeding Stock

 Selection is used as a tool for livestock improvement.

 A breeding stock is a group of males and females which act as parents of future generations.
 Selection is the process of allowing certain animals to be parents of future generations while
culling others.
 Culling is the removal of animals which do not perform to the desired level, from the herd.
 The animals retained have certain desirable characteristics which make them produce more.
 Selected animals make up the breeding stock.
 The breeding stock should pass the good qualities to their offsprings for better performance, to
improve the livestock.
 Selection process repeated for many generations increases chances of formation of desirable
qualities in an animal.
 Genetically termed as gene frequency(occurrence of the genes that carry desirable
characteristics.)
 Selection increases occurrence of desirable genes and decreases occurrence of undesirable
genes.
 During selection, the characteristics to be selected for are first studied closely to ascertain that
it is not influenced by the environment, but mainly by the genetic make-up.
 Selection helps improve characteristics which are highly heritable.
 Heritability means the likelihood of a particular trait to be transmitted to the offspring and they
are strongly inherited.
 A character like milk yield is lowly heritable, i.e. it is weakly inherited and a bigger
percentage of the character is affected by the environment.

The degree to which selection affects a character depends on the following factors;

 The heritability of the character

 The intensity with which the selection is done
 The interval between generations and kind of selection being practiced.

Factors To Consider When Selecting A Breeding Stock.

 Age
 Level of performance
 Physical Fitness
 Health
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 Body Conformation
 Temperament or Behavior
 Quality of products
 Mothering Ability
 Adaptability
 Proliferation
 Age

> Young animals,

> Those that have not parturated for more than 3-times, should be selected.

> They have a longer productive life.

> Old animals are poor breeders and low producers.

> Production and breeding efficiency decline with age.

 Level of performance

> Animals with highest production level selected.

> Performance best indicated by records.

Good performance of animal indicated by;

> High milk, wool and egg production

> Good mothering ability

> High prepotency which is the ability of a parent to pass good qualities to their offsprings.

> The animals with poor performance should be culled.

> Good records kept and used by the farmer for this purpose.

 Physical Fitness

Animals selected should be free from any physical defect

e.g.

> mono-eyed,

> limping,

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> irregular number of teats,

> scrotal hernia,

> defective and weak backline

 Health

> Sick animals do not breed well and are expensive to keep.

> Animals that are resistant to diseases pass these characteristics to their offsprings

 Body Conformation

> Animals for breeding to be selected according to proper body conformation.

> A dairy cow should be wedge-shaped with a large udder, thin legs, long neck.

 Temperament or Behaviour

> Animals with bad behaviors should be culled.eg

> Cannibalism, egg eating, aggressiveness, kicking

 Quality of products

> Select animals that give products of high quality.

 Mothering Ability

> Animals selected should have a good mothering ability,

> That is animals with good natural instinct towards their young ones.

> This will enable them to rear the young ones up to weaning.

 Adaptability

> Animals selected should be well adapted to the prevailing climatic condition in the area.

 Prolificacy

> Animals selected should be highly prolific.

> That is, animals with the ability to give birth to many offsprings at a time(larger litter).

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> This is a quality that should be considered when selecting pigs and rabbits.

Selection in cattle, and sheep,

Selection in cattle

Consider the following;

 Level Of Performance Which Include;

> Milk Yield Buter Content.

> Length Of Lactation Period.

> Calving Intervals.

 Age Of The Animal,

 Fertility,
 Physical Fitness,
 Health Of The Animal,
 Body Conformation,
 Suitability Of The Enterprise-Milk Or Beef

Selection in sheep

Consider the following;

 Level of performance which includes;

> Mothering ability

> Growth rate

> Wool quality

> Carcass quality

> Twining rate

 Age
 Suitability to the enterprise-wool or mutton
 Flocking instinct
 Health of the animal
 Physical fitness
 Inheritable defects

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 Fertility

Selection in Goats

Consider the following:

 Fertility.
 Mothering ability.
 Growth rate.
 Twining rate
 Carcass quality/dressing percentage.
 Growth rate.
 Suitability to the enterprise - milk or mutton.
 Health of the animal.
 Age. Selection in Pigs
 Consider the following:
 Carcass quality/dressing percentage.
 Suitability to the enterprise (bacon or pork)
 Growth rate.
 Health of the animal.
 Mothering ability.
 Prolificacy.
 Number of teats.
 Temperament.
 Body formation.
 Age.
 Heredity defects

Selection in Camels

 Health of the animal.

 Age.
 Temperament.
 Foraging ability.
 Fertility.
 Level of performance-milk, meat, fur and transport.

Method of Selection

These include:

 Mass selection - Animals with superior characteristics are selected from a herd and then
allowed to mate among each other.

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 Progeny testing - assessing on the breeding value of an animal on the basis of performance of
its offsprings.
 Contemporary comparison -comparison of performance between heifers of the same age and
sexual maturity.

Breeding

 Process of mating selected males and females to produce offspring with the desired
characteristics.

Reasons:

 To expand the inherited potential of the animal.

 To improve production.
 To overcome production problems created by the environment.
 To satisfy consumers taste.
 For economic reasons.

Terms Used in Breeding inheritance

 Genetic transmission of characteristics from parents to offsprings.

 The mechanism of inheritance is carried by the sex cells (gametes) and is controlled by genes
found in the chromosomes.
 Genes are very tiny units of inheritance carrying particular characteristics, such as colour,
body shape and amount of milk production.
 Chromosomes are genetic materials which carry genes.
 They exist in pairs paternal and maternal) in the nucleus f the body cells.
 They are always constant in number.

Dominant and Recessive Characteristics

 A dominant gene is one that suppresses the other.

 it produces a dominant characteristic.
 A recessive gene is one that is suppressed by the other.
 It produces a recessive characteristic.

Hybrid and Hybrid Vigour

 A hybrid is an animal which is the product of crossing animals of two different breeds.
 Hybrid vigour or heterosis is increased vigour and performance resulting from crossing two
superior breeds.

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Epistasis

 This is the masking of the effect of one gene by another gene which is non-allelic, that is
situated on different locus.

Breeding Systems

Inbreeding

 Mating of animals which are related. Reasons:

 To increase genetic uniformity in a herd.
 Used to fix the required characteristics in new breeds.
 To increase phenotypic uniformity.
 To get proven sires.

Limitations

 It can bring about loss of hybrid vigour.

 It may lead to decline in fertility.
 It may lead to high rate of pre-natal mortality.

Systems of Inbreeding

 Close Breeding: mating between very closely related animals, for example sib- mating and
parents sib-mating.
 Line Breeding: mating of distantly related animals that had a common ancestor for example
cousins. Outbreeding
 Mating of animals which are not related.

Reasons:

 To introduce new genes in an existing breeding herd.

 To exploit heterosis resulting from a cross between two breeds.
 To develop a new breed or a grade animal.

Limitations

 Lack of uniformity in animals that result from outbreeding.

 Desirable characteristics may be lost due to variation.

Systems of Outbreeding

 Cross-breeding

Mating of animals from two different pure breeds.

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 Out-Crossing

Mating of unrelated animals from the same breed.

 Upgrading/Grading up

Mating where the female of a cow grade stock (locals) is mated with a pure breed sire. The
resultant animal is referred to as a high grade.

Mating in Livestock

Mating in Cattle

 Heat signs occur every 21 days.

 The heat period last for 18-30 hours on average 24 hours.
 Cow should be served 12-18 hours after showing the first heat signs

Heat Signs

 Restlessness.
 Mounting on others and when mounted on she stands still.
 Rise in body temperature.
 Drop in milk production in lactating cows.
 vulva swells and becomes reddish.
 Clear or slimy mucus from the vulva.
 Bellowing or mooing frequently.

Mating in Pigs

 Heat signs in pigs occur after every 21 days.

 The heat lasts about 72 hours.
 Sows or gilts should be served in 18- 36 hours of the heat period.

Signs of Heat

 Restlessness.
 Frequent urination.
 Swelling and reddening of the vulva.
 Clear or slimy discharge from the vulva.
 Frequent mounting on others.
 It responds very well to the ‘riding test’.

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Mating in Rabbits

 Does are ready for mating 6-7 months of age.

 Heat signs occur every 14 days.
 The doe should be taken to the buck and not vice versa. Signs of Heat
 Restlessness.
 Frequent urination.
 Swollen vulva.
 The doe throws herself on the side.
 The doe rubs herself against the wall or any other solid object.
 The doe tries to contact other rabbits in the next hutch by peeping

Methods of Service in Livestock

Natural Mating

Advantages:

 It is more accurate.
 It is less laborious.
 Useful when heat signs of females cannot be easily detected. Disadvantages
 Inbreeding is not easily controlled.
 Transmission of breeding diseases.
 Extra feed for the male is required.
 Large males can injure small females.
 Wastage of semen.
 It is cumbersome and expensive to transport a bull to remote areas.
 Artificial insemination
 Introduction of semen into the female reproductive tract by artificial means.

Advantages

 There is economical use of semen.

 It controls transmission of breeding diseases.
 Sires that are unable to serve cows due to heavy weight or injury can produce semen to serve
cows.
 It prevents large bulls from injuring small cows. ‘
 It reduces the expenses of keeping a male animal.
 A small scale farmer who cannot afford to buy a superior bull can have the cows served at a
low cost.
 Semen can be stored for long.
 It helps to control inbreeding.
 It eliminates the threat of keeping dangerous bulls from the farm.
 It makes research work easier.

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Disadvantages

 Harmful characteristics can be spread quickly by one bull to the offsprings.

 it requires skilled labour.
 Low chance of conception due to death of semen during storage.
 It is laborious

Embryo Transplant

 It is the implantation of an embryo (fertilized ova) from a high quality female (donor) in the
uterus of a low grade female (recipient).

Advantages

 Faster multiplication of an animal with superior characteristics .

 It is easier to transport embryos than the whole animal.
 Embryos can be stored for a long period awaiting the availability by recipient females.
 It stimulates milk production in a female (recipient) that was not ready to produce milk.
 Low grade animals can be used in production and rearing of high quality animals.
 Offsprings of a superior female can spread quickly in an area.

Disadvantages

 It is expensive.
 It requires skilled personnel.
 It requires special equipment for fertilization and storage of embryos.
 Signs of Parturition in Livestock
 Parturition is the act of giving birth in female animals.

Parturition in Cattle

 The gestation period in cattle is 270-285 days averaging 280 days.

Signs of Parturition

 Restlessness
 Enlarged or swollen vulva.
 Clear mucus discharge from the vulva.
 Slackening of the pelvic muscles.
 Full and distended udder.
 Thick milky fluid from the teats.
 A water bag appears and bursts just before calving.

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Parturition in Pigs

 The gestation period in pigs is about 4 months or 3 months, 3 weeks and 3 days.

Signs of Parturition

 Restlessness.
 The vulva turns red and swells.
 The udder becomes full with a milky fluid the sow starts to prepare a nest by collecting some
beddings at one comer of the pen.
 Parturition in Rabbits
 The gestation period in rabbits is 28-32 days.

Signs of Parturition

 Preparing a nest by plucking off hair from her belly.

 Goes off feeding
 Restlessness.
 The udder distends.

Livestock Production IV

(Livestock Rearing Practice)

Introduction

 In the management of livestock there are many activities that are carried out on animals to
enhance production.
 They require care in feeding, health, breeding.
 Specific management also important in bee and fish farming.
 Routing livestock rearing practices.
 A routine is a fixed/regular way of doing something.
 done repeatedly after a certain period of time

Feeding Practice

 Animals are fed to cater for both maintenance and production requirements.
 These are special types of feeding carried out on certain animals to cater for specific needs.

These include:

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Flushing

 The practice of giving extra quality feed to an animal around service time.
 In sheep it is done 2-3 weeks before tupping and 3 weeks after tupping.
 In pigs it is done 3-4 weeks before service.

Importance of Flushing

 It increases conception rates.

 It enhances implantation of the zygote.
 In sheep it increases twinning percentage by 15-20%.

Steaming Up

 Giving extra quality feed to an animal during the last weeks of gestation.
 In cattle it is done 6-8 weeks before calving.

Importance Steaming Up

 It provides nutrients for maximum foetal growth.

 It helps in the build up of energy for parturition.
 It ensures the birth of a healthy animal.
 It promotes good health of the mother.
 It increases and maintains high milk yield after birth.

Creep Feeding

 Feeding of young animals from birth to weaning.

Piglets

 10 days old - introduced to creep pellets.

 5 weeks old - creep pellets mixed with sow and weaner meals.
 8 weeks old - weaning.

Lambs

 Run with their mothers for natural suckling.

 Bucks - introduced to succulent feeds and concentrates.

Kids

 Meat goats kids suckle naturally.

 Dairy goats, fed on milk artificially,
 Given 0.5-1.25 litres up to the third week.

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 Introduced to concentrates at 3-4 months.

 Weaned at 6-8 weeks of age.
 Parasite and Disease Control Practices

Vaccination

 Introducing active disease organsms which are reduced in strength or virulent into the animals‘
body to induce immunity.

Administration of Vaccination done through:

 By injection.
 Orally through the mouth.
 By inhalation through the nose.
 Eye drops.

Deworming

 Practice of killing/removing internal parasites by administering drugs known as deworrners /

antihelmitics.

Hoof Trimming

 Cutting back overgrown hooves with the help of a hoof trimming knife, a hoof cutter or a hoof
rasp.

importance

 Facilitate easy movement.

 Control of foot rot disease.
 Facilitate mating - prevent the ram from injuring the ewe during tupping.

Docking /tailing

 This is the removal (cutting oft) of tails in sheep during the first week after birth.

importance

 Even distribution of body fat. Facilitate

 easy mating in adult life. Minimise fouling
 of the wool with faeces. Reduce
 incidences of blowfly infestation.

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Methods of Docking /tailing

 Cutting with sharp knife or scalpel.

 Use of elastrator and rubber ring.

Dipping and Spraying

 These are methods of applying acaricides on the animals to control external parasites.

Dusting

 It is the application of chemical powders on the animal body or on the walls of the animal
house to control external parasites.
 It is used to control stick-fast parasites and fleas in poultry.

Breeding Practices

 These are practices carried out to enhance successful breeding.

 Crutching and Ringing

> Crutching - cutting of wool around the external reproductive organs of female sheep.

> Ringing - trimming wool around the sheath of the penis of the rams to facilitate mating.

Tupping and Serving

> Tupping refers to mating in sheep and goats.

> Sen/ing refers to mating in cattle and pigs.

 Raddling

> This is the practice of fitting the rams with breeding chutes which are painted in different
colours during mating

> to identify mated ewes and to indicate the active rams hence help in culling of the weak rams.

Identification

 The practice of putting identification marks on animal.

 Branding - burning marks on the animals skin.
 Ear tagging - placing marked plastic or metallic tags on the animals ears.
 Ear notching ~ cutting different shapes bearing different values on the ear lobes.
 Tattooing - use of permanent ink or dye to mark animals with light skin.
 Neck strap or chain - Fixing of tags round the animals neck with a chain or a strap.

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Importance purpose of Identification

> record keeping

> Setting disputes in case animals get mixed up in the pasture.

Debeaking

 Cutting about 1/3 of the upper beak with a knife, scissors or hot iron.

Importance

 Control egg eating.

 Control cannibalism.

Tooth Clipping

 The removal (clipping) of the needle (canine) teeth in piglets 24 hours after birth. Culling
 Removal of undesirable animals from a herd.

Dehorning

 Removal of horns or horn buds from an animal.

Importance

 It prevents animals from injuring each other.

 It makes the animal docile and therefore easy to handle.
 For easy transportation and feeding.
 Prevents destruction of farm structures.

Shearing

 The practice of cutting wool from all over the body of a sheep.
 It starts at the age of 8 months and then done once a year.
 Should be done during the dry season.
 Tools used: wool shears.
 Care must be taken not to cut the skin, testicles, udder, vulva and penis.

Castration

 It is the rendering unserviceable the testicles of a male animal.

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Importance

 To control breeding diseases.

 To control breeding.
 For faster growth rates.
 Increase quality of meat by removing unpleasant smell especially in goats.

Methods Used:

 Closed/bloodless method

> involves use of burdizzo or rubber ring and elastrator.

> Animals do not bleed but may not be 100% effective.

 Open method

>A surgical method used for castrating cocks, piglets and rabbits whose testes are internal.

> Also used for lambs, kids and calves.

> Animals bleed a lot.

> However, it is 100% effective.

> It is not recommended for mature adults.

 Caponisation

It is the practice of making male birds lose their male characteristics by use of hormones.

> Hormones used include stilboestrol which is injected into the birds when they are one day old
and female hormones implanted beneath the skin at the neck.

> Birds which have lost their male characteristics in this way are referred to as capons.

Management During Parturition

 Parturition is the act of giving birth to fully grown foetus.

Parturition in Cattle

 It is referred to as calving.
 Gestation period lasts 270-285 days after conception.

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 When the signs of parturition are observed the cow should be separated from the rest of the
herd.
 Normal calving should take 2 hours and the normal presentation is the muzzle, face or fore
head on top of the forelegs first.
 In case of other presentations the mother should be assisted.
 Provide the mother with plenty of water and feed after parturition.
 If the after birth does not come out within 48 hours a veterinarian should be called to remove
it.

Parturition in Sheep

 It is referred to as lambing.
 Gestation lasts 21 weeks (150 days) after conception.
 The ewe lamb naturally without any problem.
 If complications arise the ewes should be assisted.
 Signs of Parturition in Sheep
 Udder becomes full.
 Teats are bright red in colour.
 Restlessness and bleating.
 Slackening of the hip muscles.
 After these signs are seen the ewes should be separated from the others.
 The normal presentation is forelegs and head first.
 After birth the mother should be allowed to lick the lamb to ensure the coat is dry.

Parturition in Goats

 It is referred to as kidding.
 It takes place 150 days after conception.
 Nannies carrying twins, kid a few days earlier.
 Kidding nannies should be kept in a clean dry place which should be well sheltered.
 Signs of parturition are similar to those of ewes.
 Kidding nannies should be kept with another female for company.

Parturition in Pigs

 It is referred to as farrowing.
 Gestation period 113-117 days ( 4 months).

Signs of Farrowing

 The sow becomes restless.

 There is enlargement of the vulva .
 Muscles on each side of the tail slacken.
 There is loss of appetite.

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 The udder and the teats become enlarged.

 The sow collects bedding material in one comer to build a nest.
 Milk present in the teats 24 hours before farrowing.

After the signs are seen;

 Farrowing takes about 2-6 hours under normal condition.

 An attendant should be there to assist the mother and piglets.
 Ensure the removal of the after birth to prevent the sow from eating it.
 The sow should be fed well and given plenty of clean water.

Parturition in Rabbits

 It is referred to as kindling.
 It takes place 2832 days after conception.
 Provide a nesting box and plenty of dry soft beddings in the hutch towards the
 fourth week of gestation .

Signs of Parturition

 The doe plucks off the fur from her body.

 Uses the fur to build a nest about 3-10 days earlier.

Bee Keeping (Apiculture)

Bees are insects which live in very well organised colonies.

Each colony consists of:

 Queens - fertile females that breed to ensure the continuity of the species.
 Drones - fertile males that mate with the queen for reproduction process.
 Workers - non-fertile or sterile females that maintain the colony.

Duties of Workers

 They rear and nurse the brood (eggs, lar\/ae and pupae), queen and drones.
 They collect nectar and make honey.
 They make the honey combs.
 They protect the hives.
 They clean the hive.

Importance of Bees

 Collect nectarfrom flowers.

 Make honey - a nutritious product used by man as food.

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 Helps in crops pollination of plants.

 Bees produce wax used to make candles.
 They make propolis - a bee product which is medicinal.

Routine Management

Siting/locating of an Apiary

Factors to consider;

 Nearness or accessibility to nectar or flower-producing vegetation.

 Areas with shade. Bees are sensitive to the sun's heat and require some shade to protect them.
 Safe distance from human residence and other livestock.
 Bees are stinging insects and can be a hazard to humans or other animals.
 Nearness to a source of water for use in their nutrition.
 A good distance from source of noise and other disturbances.
 Safety from predators for example honey badgers, ants (safari ants), birds and other parasites
such as wax moths.

Feeding

 Normally bees are self-sufficient in providing theirfood from the honey they make.
 However, during the dry season, their feeding should be supplemented by providing a solution
(syrup) of sugar water or giving molasses.
 This should be placed strategically so that it is easily accessible to the bees.

Parasites

 Ants
 Wax moths
 Beelouse
 Honey badger

Control of Parasites

 Use of physical barriers such as Vaseline/grease to control ants.

 Smoke the hive to control bee louse.
 Suspend the hive to control honey badgers.
 Burn infected combs to control wax moths.

Diseases and Control

 African bees are seldom attacked by diseases. .

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Harvesting Honey

Factors to consider;

 Stage of ripening: Honey must be ha - he 't is fully mature.

 Season of the year: Harvested at the rainy season.

Procedure

 Blow light smoke through the hole.

 This makes bee ck a me engorged and docile.
 Lower the hive to ground
 Open the hive to expose the honey combs.
 Brush the bees off the honey combs.
 Cut the hon bs, ka ing a small margin on the bars and keep them in a closed contain .

Honey Processing

 Using heat in a water bath to melt the honey.

 Crushing and straining.
 centrifugal extractor.

Precautions When Handling Bees

 Avoid excessive smoking.

 This kills the brood and lowers quality of the honey.
 Use protective clothing to avoid sting.
 Protect the hive from rain water.
 Use clean equipment and containers to avoid contamination of the honey.
 Use recommended method of extracting honey.
 Use recommended type of hive such as Kenya top bar hive.

Fish Keeping (Aquaculture)

introduction

 The rearing or keeping of fish is called fish farming and is normally carried out in specially
prepared ponds.

A good fish-pond should have the following features:

 Site should be on a fairly level ground with a permanent supply or source of water.
 The area should have clayey soil to avoid loss of water through seepage.
 Water must be free from any pollutants such as chemicals and other wastes.

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Construction should provide for:

 an inlet for fresh supply of water,

 a spill way channel to take off overflow or excess water,
 an outlet to drain off the water when it is necessary to replace pond water,
 a fence to keep off predators and other intruders.

Feeding Fish

 Fish naturally feed on worms, insects and algae in the ponds.

 These sources of food must be supplemented by throwing in the pond ;
 kitchen wastes,
 chopped vegetable materials such as cabbage leaves,
 cereal brans
 brewers’ grain .

Management Practices to Ensure Maximum Harvest of Fish

 Control of stocking rate, that is to, have the recommended population of fish in a pond at
anyone time.
 Harvest at the correct maturity stage.
 This is done by using the fishing net with correct mesh sizes to avoid catching the fingerlings.
 Avoid water pollution in the ponds which may poison fish.
 Ensure adequate supply of food in the pond.
 Water in the ponds should be kept in motion to facilitate aeration.
 Maintain appropriate depth (level) of water.
 Control predators and/or thieves.
 Drain and refill ponds with fresh water as necessary.

Harvesting Fish

 Harvesting or extracting fish from the fish ponds for consumption

Two main methods:

Hook-and-line method:

> This is slow, injures small fish and is inefficient.

> It is only suitable for small-scale fishing.

Use of fishing nets:

> This is the most efficient method as long as a net with the correct mesh sizes is used.

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> Harvesting may be done 6-8 months after the introduction of fingerlings into the fish pond.

Maintenance of the Fish Pond

 Repairing the dyke or any structure on it.

 Cleaning the pond and removing foreign materials.
 Planting grass where necessary.
 Removing undesirable vegetation.
 Removing the silt.

Fish Preservation

Practices before preservation:

 Clean the fish to remove mud and any worms.

 Removing scales and slime.
 Opening the fish on the side to remove the gut and the intestines referred to as gutting.
 Cleaning the abdominal cavity thoroughly.
 Keeping fish in open containers.

Methods of Preservation

 Freezing
 Salting
 Sun drying
 Smoking

Appropriate Handling of Livestock During Management

 Physical beating should be avoided.

 Structures which help in restraining animals should be used whenever applicable.
 The correct methods of securing and casting animals should be used.
 Use as little force as possible.
 Equipment such as ropes, halters, lead stick and bull rings are used to handle animals
appropriately.

Farm Structures

Introduction

 Farm structures are physical constructions on the farm used to increase efficiency in
production.

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Construction of Farm Structures

Involves:

Planning for farm structures ;

Consider;

 Farm activities.
 Size of the enterprise.
 Future of the enterprise.
 Accessibility.
 Soil type.

Siting farm structures;

Consider:

 The location of the homestead.

 Accessibility.
 Security.
 Drainage/topography.
 Wind direction.
 Relationship between the structures.
 Proximity to social amenities.
 Farmer's taste and preference.

Materials for Construction

Structural Materials and Use

Factors which determine the type of materials to use are;

 durability,
 strength,
 labour,
 availability,
 workability,
 serviceability,
 cost
 sanitation.
 Stones and Bricks

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Advantages

 Stones and bricks are durable, easy to disinfect, resistant to weather and insects decay and are
easily available.

Disadvantages

 They are bulky and require skilled labour to make them.

 Plastic and Synthetic Materials

These include;

 glass,
 asbestos fibre
 polythene materials.

Advantages

 Light,
 cheep depending on quality,
 easy to disinfect,
 can be moulded into any shape,
 are durable,
 cannot be destroyed by insects and fungus
 are water-proof.

Disadvantages

 Are easily destroyed,

 fragile,
 very expensive
 require skilled labour.
 Wood (Timber)

Advantages

 They are workable,

 cheap,
 can be re-used
 are fairly strong.

Disadvantages

 They can catch fire easily,

 decay if exposed to water
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 are affected by fungus and insects.

Concrete

 ls a mixture of cement, sand, aggregate and water

 e.g. in making blocks the ratio is 1:223; one part cement, two parts sand and three parts
aggregate.

Uses

 Making posts for fencing.

 Making walls and floor of buildings.
 Making gabions and water channels to prevent erosion.
 Making water troughs.

Advantages

These materials are;

 durable, workable,
 easy to disinfect,
 cheap to maintain,
 fire resistant

Disadvantages

These materials are;

 expensive,
 require skilled labour,
 bulky,
 cannot be reused

Animal handling structures

 The crush —used when doing following activities;

Spraying livestock to control ticks,

milking,

examining sick animals,

> artificial insemination,

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> treating animals, eg drenching, vaccination,

> dong routine jobs such as dehorning, identification marks,

 The spray race-used in the control of ticks by spraying livestock with acaricides
 The dip- machakos type, and the pludge dip. This is used in the control of ticks by dipping
livestock

Farm Buildings

Factors to be considered in site selection;

 Security
 Nearness to a source of water
 Topography
 Direction of the prevailing wind
 Direction of the sun
 Personal whims/tastes and preference
 Nearness to means of communication.

Types of farm buildings

 Houses for farm animals.

 Stores for farm produce.
 Stores for equipment, tools and supplies.
 Buildings for growing crops e.g green house.
 Building for processing plant e.g milk plant.

Parts of a building

 The foundation,
 The walls,
 The roof

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Parts of a Roof

Include;

 kingpost,
 rafters,
 struts,
 tie beam,
 rafter batten

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parts of a wall

Pants of the foundation

Include;

 concrete floor,
 foundation wall,
 PVC sheet (damp-proof course)
 the compacted fill (hard core).

Fences

 Importance of Fence in a Farm

 Keep out intruders to the farm,
 Define the boundary lines of the farm.
 Paddocking of fields to make rotational grazing possible.
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 Live fences serve as windbreaks.

 Fences are used in mixed farming to protect crops from damage by livestock
 Fences add aesthetic values to the farm.
 It is easy to control breeding.
 It is easy to isolate sick animals from the rest of the herd. of Fences

Types

 Dead fences.
 Barbed wire fences.
 Electric fence.
 Concrete fence.
 Chicken wire fence (mesh wire fence).
 Woven wire fence (chain link).
 Wooden fence.

Fencing Practice

 Materials include;

>wires,

>staples,

>nails,

>posts,

>droppers

>concrete materials.

 Size of posts:

> General purpose 2.5m by 25cm in diameter

> Strainer units and corner posts 3m by 30cm in diameter:

 Distance between the posts:

3m between posts, 10m if droppers are to be used.

> zoom between strainer units.

 Depth of holes - 60cm.

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Gate Posts, Gates and Strainer Units

 Gates should be hung on posts separate from the fence.

 Mechanical implements for example tractors require 4.0-4.5m width of gate.
 Entrance gates for pedestrians can be accommodated within the fence.

Steps in Fencing

 Locate the corners

 Clear the fencing area.
 Mark gates, strainers, pass places and standards by pegging.
 Dig holes to proper depths.
 Fix the standard posts.
 Firm around posts or apply concrete.
 Fix wires on posts.
 Fix the droppers.

Agricultural Economics ll (Land Tenure and Land Reforms)

Introduction

 Land is an important factor of production.

 Without land it is impossible to practice the agricultural business.
 However the efficiency of utilization of land is influenced to a large ex condition of holding
the land.

Land Tenure

 Land tenure is defined as the possession of the legal rights to the use of land.
 Various kinds of rights to the use of land give rise to different tenure systems

Land Tenure System

 All land tenure systems fall into two major classes, namely:

Collective Tenure Systems

This includes:

Communal Tenure Systems

 This involves the possession of rights over land by the whole community.
 It works quite well under conditions of unlimited land resources.

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Advantages of Communal Tenure

 Landless problem does not exist.

 Land is not fragmented.
 Allows for free movement of animals in search of better pastures and water.
 Promotes community spirit among the members.

Disadvantages of Communal Tenure

 No incentive among the users to conserve the land resources.

 Everybody strives to maximize returns from the land without the drive to invest, for example,
in terms of soil conservation and maintenance of soil fertility.
 There is a tendency of overstocking and continuous cropping; which leads to soil erosion and
loss of land productivity.
 As a result of communal grazing of livestock, it is impossible to improve livestock through;

> controlled breeding,

proper feeding,

> disease and parasite control.

 Since there is no title deed, (certificate of ownership) it is virtually impossible to secure loans
to develop the land.

Co-operative Tenure System

 This category includes various collective arrangements under the government or other
authorities.
 Farmers voluntarily group together and buy land which they subsequently operate on co-
operative basis.
 Examples are co-operative ranches.

Advantages of Co-operative Tenure

 No land disputes.
 Labour is well utilized.
 Profit is distributed according to the number of shares.
 Resource use is enhanced for high production.

Disadvantages of co-operative tenure.

 Incase of poor management everybody will loose.

 No individual title deed hence cannot secure loans.

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State ownership

 Land is owned by the whole state and is refered to as government land.

Examples in Kenya;

 Areas not allocated to individuals

 Land under local county councils/cities and towns
 Land under forest, game reserve and parks, land for infra-structure and public utility

Advantages of state ownership

 Generation of income for the state

 All the citizens benefit from whatever comes out of the land.

Disadvantages

 Non-competitive in terms of production

 No individual motivation when working on the land.

individual Tenure system

The various forms of individual land tenure are;

 Owner operator,
 Plantation and Concestion,
 Land-lordism/Tenancy

Owner operator

 This category includes all persons who operate on land to which they have absolute individual
rights.
 Examples are the majority of individual land owners in areas where demarcation and
registration of land has taken place and title deeds issued.

Advantages

 The owner is free to make permanent production plans.

 The owner can pledge the land title deed to secure loans(credit) from lending agencies for
further development
 An individual is motivated to work harder than when under communal arrangement
 Managerial failures usually affect small units of production and are therefore negligible
 It is easy for the owner to get agricultural advice.

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Disadvantages

 Cost such as machinery for processing may be too high for the individual owner
 Innovation may be inadequate due to low levels of education.
 Lack of capital to invest.

Plantation and concession

 In this form of land tenure, the individual is usually a company or a corporation.

 Most of them engage in the production of only one commodity
 They are rigid in their production plans and in most cases labour is hired on wage basis.
 Example are coffee, tea, sugarcane, sisal estates in Kenya.

Advantages

 High production from the land hence high economic gains

 Allows foreigners to use and develop land
 No land disputes
 Create employment for the local people
 Generate government revenue through taxation.

Disadvantages

 Individuals own large pieces of land while others are landless

 Large areas of land may be left underdeveloped.
 Foreigners may repatriate profit to their countries.

Landlordism and tenancy

 The arrangement here involves the ownership of land by one individual or group of
individuals (landlord) who lease it to another individual (tenant).
 A legal lease specifies the length of time during which the tenure is operative; and that serves
as a security of tenure to the tenant.
 The efficiency of production in this arrangement is greatly affected by the length of lease, its
legal backing and rent payable.

Advantages

 A person without land can get a chance to use land.

 A landlord who cannot operate the land, for any reason, can still earn income by leasing it to a
needy tenant.
 It is a flexible arrangement; that is, it allows room for change of production plans should need
arise.
 Security of tenure gives the tenant incentive to invest depending on the length of tenure.

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Disadvantages

 Poor land use and low production if the tenant does not have enough funds to improve on land.
 Tenants cannot produce long term crops,
 Landlords can exploit the tenants by overcharging.
 Lack of incentives to improve land by the tenants since it does not belong to them.

Land Reforms

Definition

 Land reform is any organized action designed to improve the structure of land tenure and land
use.

Forms of Land Reform

Land Consolidation

 This means bringing or putting together, into one piece; fragmented parcels or pieces of land
scattered over a large area.

The objective of land consolidation are :

 To save on time spent while moving from one piece of land to another.
 To facilitate effective and efficient farm planning.
 To create an incentive among land operators to invest on and develop land.
 To facilitate mechanization and improve production through efficiency.
 To improve level of production through effective supervision of the labour force and sound
farming methods,

Land Fragmentation and Sub-division

 This is the subdividing of a (large) piece of land into smaller portions.

 Sometimes it becomes necessary to sub-divide land for the following reasons:

> To sell part of the land.

> The parent may wish to subdivide and distribute his land among the sons, daughters and other
dependants.

> The government may decide to subdivide large farms in order to settle landless citizens.

Land Adjudication and Registration

 Land adjudication involves;

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> Establishing the legitimate ownership,

> Measurements (to make permanent boundaries)

> Recording of land details.

 Once land has been adjudicated, and an disputes concerning the sarne land are settled,
 It is then registered in the "Register ofVLand".
 And the owner is issued with a land title deed or certificate of legal ownership.

Importance of land title deed

 The legal owner of the land has security of tenure and hence an incentive to invest and
improve productivity.
 A farmer can mortgage the land by offering land title certificate as a security to loaning
agencies to secure capital to finance development projects.
 If a farmer who cannot operate the farm, he can still earn income from it by leasing it.
 Disputes concerning land boundaries and/or land ownership no longer arise.

Land Settlement and Resettlement

Definition

 Land settlement means the occupation of land which was previously uninhabited.
 Land resettlement, on the other hand, is the transfer of people from an already densely
populated area to a sparsely populated one.

Objectives

 To settle the landless citizens.

 To relieve population pressure in densely populated areas.
 To increase or promote agricultural productivity by farming on land that was previously
unused or lying idle.
 To create self-employment thus improving the living standards.
 Land reclamation, especially by creating tsetse fly-barriers.

Soil and Water Conservation

Introduction

 Soil and water are two very important natural resources in farming.
 They should therefore be well maintained and used without wastage to sustain continuous
production.
 Water loss during the rainy season should be prevented and excess water conserved for use
during scarcity.

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 Soil erosion must be controlled at whatever cost if soil is to be conserved.

Soil Erosion

 It is the removal and carrying away of the top soil by the action of water or wind.

Factors Influencing Soil Erosion

 Amount and intensity of rainfall.

> The steeper the land the higher the velocity of surface runoff.

> The higher the velocity of surface runoff the greater is its erosive power/effect.

 Type of soil for example sandy soils are more easily detached and carried away than clayey
soils.
 Soil depth;

> The deeper the soil, the longer it takes to be saturated with water.

 Land use:

> Overstocking leads to bareness of the land and looseness of the soil.

> Deforestation - indiscriminate removal of trees leads to exposure of soil to > heavy rainfall and
high temperatures.

> indiscriminate burning of vegetation exposes the soil to erosive agents.

> Clean weeding leaves the soil bare.

> Ploughing along the slope.

> Monoculture or continuous cultivation.

 Ground cover

> Trees act as windbreakers.

> Roots of vegetation cover hold the soil particles together.

> Leaf fall act as mulch which reduces erosion.

> Leaves of vegetation cover intercepts raindrops reducing their erosive power.

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Agents of Erosion

 Water - moving water has erosive power.

 Wind - wind carries away soil.
 Human beings - through man's activities such as cultivation and mining.
 Animals - through overgrazing and creating footpaths where soil erosion takes place.

Types of Erosion

 Raindrop (splash) - displacement of the soil caused by raindrops.

 Sheet - uniform removal of soil in thin layers from flat or gently sloping areas.
 Rill - removal of soil from small bur well defined channels or rills.
 Gulley - removal of soil from channels which become progressively deeper and wider.
 Riverbank Erosion - removal of soil along river banks by the river water.
 Solifluction - gravitational flow of soil saturated with water.
 Land slides - mass movement of rock debris and soil down a slope,
 For example;

> Slip movement of earth or rock masses for a short distance.

> Debris slide - materials move at a greater speed.

> Debris fall - movement of materials/debris along vertical cliff.

> Rock fall - movement of rock down a very steep slope.

> Rock slides - mass of rock materials that slide along a bedding plate, a joint or a fault face.

Soil Erosion Control Measures

Soil conservation measures can be classified into:

 Biological or cultural control

 Physical or structural control

Biological or Cultural Control Measures

These measures are applicable where land slope is between 2-12%.

 Grass strips/filter strips;

> These are narrow uncultivated strips along the contour left between cultivated strips.

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 Cover cropping;

> The establishment of a crop that spreads out over the surface of the soil to provide it with a
cover.

 Contour farming;

> Carrying out all land operations along the contour.

 Mulching ;

> Covering of the soil with either organic or synthetic materials.

Proper cropping systems such as:

> Crop rotation

> Correct spacing

> Inter-cropping

> Ridging/furrowing

> Strip cropping

 Controlled grazing;

> Proper stocking rate, rotational grazing.

 Strip cropping;

> Growing crops which give little ground cover in alternate strips with crops such as beans
which have a good ground cover.

 Afforestation/re-afforestation.

> Afforestation ~ growing of trees where non-existed.

> Re-afforestation - growing of trees where they have been cut down.

> Agroforestry - land use that involves the growing of trees in combination with crops and
pastures on the same piece of land.

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Physical or Structural Control Measures

 These are soil and water conservation measures which involve mechanical constructions on
the earth.
 They are used in areas of moderate slope between 13-55%.

They include:

 Trash or stone lines; > These are rows of heaped crop’ residues or stones made along the
contours.
 Filter strips;

> It involves the growing of an open crop in the upper side of the slope followed by a dense crop
to reduce speed of water.

This increases infiltration.

 Terraces;

> Are structures constructed across a slope to reduce the length of a slope thus reducing run-off.

 Bench terraces;

> Are constructed where the slope is 35-55%.

> Tree crops are suitable for such areas.

Importance of a Bench Terrace:

> Reduces slope of the land.

> Conserves soil moisture.

> Better retention of soil fertility.

 Narrow based terraces —Cannot allow cultivation by machines.

 Broad based terraces - ls wide enough to allow cultivation by machines.
 Graded terraces:

> Have a drainage channel to lead off excess water to a vegetated place.

> They should be about 100m in length.

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 Level terraces:

> Have no outlet channels,

> The aim is to have water infiltrating,

> Hence no water can flow from the ends of the terrace.

 Fanya juu:

> A ridge made by digging a channel and throwing the soil uphill.

 Fanya chini:
 In this case the soil is heaped on the lower side of the channel.
 Bunds: heaps of soil (earth) made along the contour.
 Cutoff drains:

> An open trench with an embankment on the lower side into which water from the farm drains.

Water from the trench should be discharged into;

> Natural waterways,

> Artificial waterways,

> Rocky ground

> Grassland

 Gabion/Porous dams:

> Galvanized wire mesh boxes filled with stones which are built across slopes and gullies.

 Dams and reservoirs ;

> Dams - barriers built across ariver/waterway to hold and store water. It reduces speed of
runoff.

> Reservoirs - these are large storage tanks.

 Ridging - heaps of soil to reduce the speed of water,

They retain the water for some time.

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Water Harvesting Methods

 Water harvesting and storage should be done during the rainy seasons to avoid wastage.

This should be done using the following methods:

 Roof catchment - trapping and collection of rain water from roof tops.
 Rock Catchment - water is harvested by constructing a barrier on the lower side of a large
impervious rock to trap surface runoff from the rock.
 Weirs and dams.<

>Dam - a barrier constructed across a river or a dry valley so that it can hold water. >Weirs -
barriers constructed across a river or a stream to raise the water level and still allow water to flow
over it.

 Ponds - water retention excavations made to hold excess surface water.

 Retention ditches/level terraces.-These are terraces constructed with blocked ends to retain
water.

Micro-Catchments

 A system of harvesting limited rainfall and storing the water in the ground for use by the
planted crops.

Types of Microcatchments;

 Triangular/V-shaped/Negarims;

> V-shaped bunds measuring 25cm

> Are built with soil from the excavated planting holes to direct runoff water towards the basin
area around the base of each plant

 Semi-circular bunds;

> Formed around the growing plant to hold water around the plant.

 Trapezoidal bunds;

> Trapezoidal shaped bunds, which enclose a large area where the crops are grown.

 Contour bunds/furrows ;

> These are furrows made along the contours between the rows of crops where agroforestry trees
are intercropped with annual crops.

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 Planting holes/pits;

> These are extra large planting holes made and filled with dry plant materials before filling in
with soil.

Use of Micro-Catchments

 Slow down the speed of surface runoff.

 Used during landscaping of the compound, parks and roadside nest areas.
 Reclamation of land forfood crop in dry areas.
 Water collected and stored can be used for irrigation
 Afforestation in dry areas.

Weeds and Weed Control

Introduction

 Weeds cause heavy crop losses if not controlled.

 Their control is important so as to maintain high quality and quantity produce.

Definition:

 A weed is any plant growing where it is not required.

 And whose economic disadvantages outweigh the advantages.

Harmful Effects of Weeds

 Weeds compete with crops for nutrients, space, light and soil moisture.
 Some weeds, for example, Striga spp are parasitic to cultivated crops such as maize.
 Some weeds lower the quality of agricultural produce for example:

> Mexican marigold gives undesirable flavour to milk if dairy cows feed on it.

> Devils horsewhip, black jack, bristly fox-tail and others get attached to sheep

 wool thus lowering its quality.

 Some weeds are poisonous to human beings and livestock for example:

> Thorn apple (Datura stramonium)

> Sodom apple (Solanum incanum)

 Some weeds have allelopathic effects to cultivated crops.

 Water weeds block irrigation channels.

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 Aquatic weeds such as Salvinia in Lake Naivasha and water hyacinth in Lake Victoria affect
fishing.
 Some weeds are alternate hosts for insects, pests and disease causing organisms for example:

> Wild oat (avena fatua) is an alternate host for rusts.

> Mallow (malva verticillata) is an alternate host for cotton stainers.

 Weeds lower the quality of pasture for example:

> Tickberry (Lantana camara)

> Nut grass (Cyperus rotundus),

> Manyatta grass (Eleusine jaegeri)

 Some weeds irritate workers thus reducing the efficiency in which they are controlled for
example:

> Double thorn (Oxygonum sinuatum),

> Stinging nettle (Urtica massaica) ,

> Devil's horse whip (Achyranthes aspera).

Factors Contributing to the Competitive Ability of Weeds

 They produce large quantities of seeds for example pigweed and black jack.
 Their seeds remain viable in the soil for a long time awaiting conducive germination
conditions.
 They have effective seed dispersal mechanisms.
 Some weeds propagate by means of elaborate underground storage structures.
 They are efficient in utilizing little moisture, nutrients and sunlight.
 Some have short life cycles.
 They have elaborate root systems for supporting the plant and absorbing nutrients and water.

Weed Classification

it is based on:

Life cycles for example:

> Annuals - complete their life cycle in only one season.

> Biennuals - complete their life cycles in two seasons only.

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> Perennials - complete their life cycle in more than two seasons.

Morphology - leaf formation such as size, shape and venation.

> Broad leaved weeds for example black jack, lantana, pig weed, oxalis and others.

> Narrow leaved weeds for example couch grass, setaria, nut-grass, manyatta grass and others.

Habitat - some weeds are terrestrial (grow on land) while others are aquatic (grow on
aquatic/marine conditions).

Weed Identification

 Weeds are identified by their common (individual) names and botanical names.
 They are named according to specific features or according to person who identified them.

Common Name .....Botanical Name

 BlackJack ......Bidenspilosa
 Mexican marigold .. Tagetes minuta
 oxalislsorrel .... ..Oxali5 spp.
 Double thorn ......Oxygonum sinuatum
 Thorn apple .. . ..Datura stramonium
 Couch grass .. ..Digitaria scalarum
 Nut grass .... .. . ..Cyperus rotundus
 Wandering Jew .. Commelina bengalensis
 Sow thistle .... .. ...5onchus ole race us
 Devil's horsewhip .Achyranthes aspera
 Macdonald's eyel Gallant soldier. Gallinsoga parviflora
 Sodom apple .Solanum incanum
 Black night shade ..S0lanum nigrum
 Chinese lantern... .. .. Nicandra physalodes
 Bracken fern ....... .. ..Pteridium aquillium
 Love grass] Bristly foxtail .Setaria verticillata
 Cleavers .. ...Gallium spurium
 Stinging Nettle .. ..Urtica massaica
 Fat hen/Goose foot . ...Chenopodium spp.
 Rapeweed........... ......Bras5ica nap us
 Wild oats ....... .. ...Avena fatua
 Lantana/Tick berry Lantana camara
 Water hyacinth .. .Eichhornia crassipes
 Striga/Witch weed Striga hermontheca
 Creeping indigo .. Jndigofera spicata

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Weed Control Methods

The methods of weed control determined by:

 The weed being controlled.

 Weather conditions.
 Capital availability.
 Effect on environment.

Methods of weed control include:

Chemical Weed Control-

 The use of chemicals known as herbicides to control weeds.

Classification of Herbicides

Based on:

 Formulation - the physical form of the herbicides for example:

> Liquids

> Wettable powders

> Emulsion

> Dust

 Time of Application

> Pre-emergence - applied before the planted crop germinates.

> Post emergence - applied after the planted crop germinates.

 Selectivity

> Selective.

> Non selective.

 Mode of Action

> Contact - herbicides that kill only the parts of the plant which it comes into contact.

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> Translocated systemic herbicides that will kill the whole plant even if it comes into contact
with only a small part of it.

Methods of Herbicide Application

 Spraying - application of solutions.

 Dusting - application of dusts.
 Fumigation - application of fumigants into the soil.

Safety Measures in the Use of Chemicals

 Read manufacturer's instructions and follow them.

 Wear protective clothing such as overalls, breathing mask, gloves and boots.
 Avoid inhaling the herbicides.
 Wash thoroughly after handling chemicals.
 Do not blow or such blocked nozzles.
 Avoid herbicide drift to unintended crops and other plants.
 Avoid herbicide drift to livestock feed and water.
 Avoid spilling herbicides in pastures and fodder crops.
 Dispose off the empty containers properly for example burying them in the soil.
 Do not wash spraying equipment in water sources used by animals and human beings.
 Store chemicals in a safe place.
 Wash the spraying equipment thoroughly.
 Sink left over chemicals into the soil after the day's work.

Advantages of Chemical Weed Control

 It is less laborious.
 Effective in the control of difficult weeds such as couch grass and sedges.
 It does not disturb crop roots and other underground structures.
 It makes the control of weeds in certain crop easier.
 It is efficient in both wet and dry conditions.
 It does not destroy soil structure.
 Cheaper in large scale production than the use of manual or mechanical cultivation

Disadvantages of Chemical Weed Control

 It requires skilled labour in mixing and application.

 Cause environmental pollution.
 Herbicides have long residual effects which may interfere with future crops.
 It is very expensive.

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Mechanical Weed Control

 It involves the following operations:

 Tillage/Cultivation
 This is the opening and loosening up of the soil.
 lt can be done by hand tools or tractor drawn implements.

Advantages

 Cheap in small scale production.

 Increases water and air infiltration into the soil.
 Incorporates crops residues into the soil.
 The earthing-up done during tillage encourages root growth.

Disadvantages

 If done repeatedly it destroys soil structure.

 It is laborious and expensive in large scale production.
 It may not effectively control weeds.
 It may lead to soil erosion and loss of soil moisture.
 Damage crop roots.

Slashing/Mowing

 Mechanical removal of shoots from weeds.

 It is effective in the control of annual weeds.

Uprooting

 It is done when the crops are too close

 To allow mechanical cultivation or where weeds are scattered.

Cultural Weed Control

It involves the following practices:

 Mulching.
 Cover cropping.
 Crop rotation.
 Timely planting.
 Use of clean seed/planting materials.
 Proper spacing.
 Proper seedbed preparation.
 Flooding.

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Biological Weed Control

 The use of living organisms to control weeds.

Examples are:

 Use of livestock to graze and control growth of weeds especially in plantations.

 Use of weed eating fish to control aquatic weeds.
 Use of moths to control cactus. Limitations: the method is not reliable.

Legislative Weed Control] Quarantine

 It involves government laws and regulations which prevent the introduction and spread of
foreign weeds in a country or an area. Done by KEPHIS.

Limitations: Only samples are checked while the bulk of the materials may have some weed
seeds.

Crop Pests and Diseases

Introduction

 Crop pests and diseases lead to high losses in crop production hence efficient control measures
are needed.
 Proper control measures require the farmers to be able to;

> Identify these organisms,

> Know their life cycles, feeding habits

 The damage they cause to crops.

Crop Pests

Definition of a Pest:

 It is a living organism that destroys crops/ trees either directly or indirectly by introducing
pathogens (disease causing germs).

Classification of Pests

Pests are classified according to the following:

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 Mode of Feeding

> Pests with biting and chewing mouth parts - they cause physical damage and reduce the
photosynthetic area of the plant.

> Pests with piercing and sucking mouth parts - they suck out the nutritious plant sap and in the
process may introduce disease causing organisms.

 Crops Attacked

> Some crop pests attack specific crops for example, stem borers prefer cereal crops.

 Stage of Growth of Crops Attacked

> There are pests of seedlings attack when the crop is young, for example cutworms.

> Pests of fruits - attack the crops at fruiting stage.

> Pests of grains attack the crops when the grains are formed.

Field and Storage Pests

> Some pests attack the crops while in the field.

> Other pests attack the produce after it has been harvested and stored.

Identification of Common Pests

imagetable44

 Beetles - field and storage pests.

 Birds - field pests - cereals and fruits.
 Rodents - field and storage pests ,cereals and tubers.
 Nematodes - soil borne pests - tomatoes, potatoes, sunflower, beans.

Harmful Effects of Crop Pests

 Pests such as squirrels and rodents, unearth planted seeds, resulting in poor germination.
 Some pests like nematodes, termites and moles damage crop roots causing wilting and death
of the crops.
 They lower the quality and quantity of farm produce.
 They increase the cost of production since farmers will incur expenses in purchasing
chemicals to control them.
 They transmit diseases to crops for example, aphids transmit streak virus disease in maize.
 Chemicals used to control the pests cause pollution to the environment.

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 They exterminate the crop by feeding on them for example eating embryo of the seed.

Control of Pests

 If pest population causes damage beyond tolerance then it is said to have reached economic
injury level (EIL) hence control measures should be effected before this level.

Before any control measure is effected ,the following should be considered:

 Know the life cycle of the pest.

 Correct identification of the pest.
 Correct assessment of the damage.
 The weather conditions.
 The value of the crop in question.
 The cost factor of the control method.

Methods of Controlling the Pests

 Cultural methods.
 Physical/mechanical measures
 Biological methods.
 Chemical methods.
 Integrated pest management.

Cultural Methods:

 These are farming practices which aim at reducing the pest population by destroying the life
cycle of the pests either by exposing them to adverse conditions or denying them food.

These include:

 Timely planting to escape pest attack.

 Timely harvesting.
 Proper tillage.
 Close season: this is the period when a susceptible crop is not grown in order to control a
certain pest.
 Trap cropping: These are crops which attract pests diverting them from the main crop. The
trap crop is grown together with the main crop.
 Crop rotation: It breaks the life cycle of the pest.
 Planting resistant varieties: These are plants with natural protective mechanisms against pest
for example hairy cotton against jassid bugs, goose necked sorghum against birds, high tillering
in sorghum against shoot fly.
 Field hygiene: This includes rogueing and removal of crop residues which harbour pests from
field.

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 Alterations of environmental conditions, such as, creating a microclimate which is not

conducive to pests for example open pruning in coffee.
 Crop nutrition: application of fertilizers and manures to make the crop strong and able to
escape pest attacks.
 Destruction of alternate hosts, for example, weeds like mallow which harbour cotton stainers.
 Use Of clean planting materials. This helps to prevent introduction of crop pests.
 Proper spacing: if well spaced some pests find it difficult to move from one plant to another.
 Use Of organic manure, for example, farmyard manure discourages eel worms (nematodes).

Chemical Control

 Chemicals used to control pests are known as pesticides.

 Pesticides are administered through dusting, spraying or fumigating.

Classification of Pesticides:

Pesticides are classified on the basis of:

Mode of Entry

 Stomach - ingested by the pest together with the crop materials.

 Contact - absorbed through the body tissues.
 Fumigants - through the breathing mechanism.
 Systemic - translocated to all parts.

Mode of Action

 Respiratory poisons - interfere with breathing mechanisms.

 Coagulants - cause the blood of the pest to coagulate.
 Neurotoxins - act on the nervous system.
 Protoplasmic poisons - cause the cells to disintegrate.

Target Pests

 Insecticides - kill insect pests

 Molluscicides - kill snails and slugs.
 Rodenticides - kill rodents.
 Nematocides - kill nematodes.

Formulation .

 Dusts, granules and powders

 Emulsifiable concentrates.
 Miscible liquids.
 Wettable powders.

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 Fumigants.

Factors That Affect the Efficiency of Pesticides

 Concentration of the pesticides.

 Weather conditions at the time of application.
 Timing of application - ef-ficiency is high if applied when the pest is most susceptible.
 Persistence of the pesticide having long residual effect in the soil.
 Resistance of the pests.

Advantages of Chemical Pest Control

 Faster
 Immediate results are achieved.
 Low labour requirements.

Disadvantages of Chemical Pest Control

 Expensive to buy.
 Cause pollution to the environment.
 Require skilled labour to apply.
 Some pesticides may kill beneficial organisms and predators.
 Some target pests may build up resistance.

Mechanical Pest Control/Physical

 This involves the killing of the pests using physical methods. Or creating physical barriers to
prevent pests from getting into contact with the crops.

Example:

 Flooding/irrigation; for example, moles are suffocated through flooding.

 Use of lethal temperatures: either too cold or too hot.
 Suffocation; commonly used in grain storage bins by being made airtight.
 Trapping and killing, for example, rats.
 Creation of physical barriers, such as, rat bafflers, sticky materials on tree trunks.
 Proper drying: this makes them too hard to be destroyed by pests.
 Scaring devices especially in rice plantations to control birds.
 Use of explosives thrown at breeding places of birds to kill or scare them away.

Biological Pest Control

 It involves the use of living organisms to reduce the pest population. Predator ...........Target
Pest
 Parasitic wasp-------------------White fly in citrus, boll worms, stalk borers
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 Birds ------ Crickets, locusts, caterpillar llars.

 Lady Bird
 Trachnid flies -------------------cotton stainer
 Praying mantis-----------------giant loppers
 Maiimoto ants -----------------scales
 Cats ---------------- ------------------mo|es,rats,mice
 Brachonid wasps ----------- --mealy bugs
 Chicken ------------- --cotton stainer, larvae of beetles, grasshoppers, crickets

Advantages

 Cheap
 No environmental pollution
 Saves on labour.

Disadvantages

 Takes too long to get the correct agent

 Difficult to control the pest effectively.

Integrated Pest Management

 It is a new metho which involves the combination of the methods mentioned above.
 The aim is to have least hazards to the user and to the environment.
 Example, attractant-pheromones are used to attract pests to one place where they are sprayed
and eradicated.

Legislative Method/Quarantine

 Legislative mearsures of pest control are effected by the Kenya Plant Health
 Inspectorate Service(KEPHlS) through seed inspection.

Crop Disease And Their Control

 A disease is any deviation from the normal performance or functions.

 A plant disease is any harmful physiological disorder in a plant caused by pathogenic agents
such as virus, bacteria, fungi.
 The study of plant disease is called plant pathology.

Economic importance of crop diseases

 They lower crop yield

 They reduce the quality of the produce thus reducing their market value
 They cause food poisoning. E.g ergot in wheat, afflatoxin in grain crops by fungus.
 They reduce photosynthetic area of the plant.
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Classification and identification of plant disease

 Plant disease are classified according to their causal agents;

Fungal diseases;

 Fungi are non-green plant-like.

 Some are parasitic and others are saprophytic.

Parasitic fungi divided into;

 Obligate parasites- those that depend on other living organisms for food.
 Falcultative parasites-those that are able to live on both the living and dead tissues.

Examples of fungal disease

 Panama disease(Fusarium oxysperium—bananas)

 Cigar-end rot(Verticilium theobromae)-bananas
 Die back —attack the tips of shoots and roots
 Mildews-foliar disease of several crops
 Armillaria root rot(Armi||aria mellea)-coffee and tea
 Damping off-disease of seedlings in the nursery
 Anthracnose (Colletotrichurn spp)-coffee,beans,tomatoes.
 Fungus also cause damage to stored grains which are not properly dried or if the store is damp.
 Fungus cause food poisoning and lower seed viability for example Aspergillus flavus which
produces a highly toxic compound called afflatoxin.

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Examples of fungal disease

Bacterial Diseases

 Bacteria are microscopic single-celled organisms which reproduce by binary fission

 Transmission; Through irrigation water, seeds, fertilizers, manures, wind, raindrop splash,
insects, soil and mechanical means.

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Symptoms of Bacterial Diseases

 Wilting
 Cankers(necrotic tissues)localized necrosis
 Gall formation in infected tissues.

Examples of bacterial diseases

Viral Diseases

 Viruses are small living organisms which can only be seen under a very powerful electronic
microscope.
 Viruses interfere with photosynthesis, respiration, transpiration and nitrogen utilization

Symptoms of Viral infection

 Leaf chlorosis.
 Leaf curling.
 Mosaic(light green or yellow patches).
 Malformation(distortion)of plant parts.
 Rosettes; Development of abnormally short internode.

Transmission

 Through the use of infected vegetative materials and insect vectors like aphids, mealybugs and
leafhoppers.

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Viral diseases

Other Causes of Crop Diseases

 Flooding forming ammonia which is poisonous to the crops causing a burning effect on leaves.
 Chemicals: some may be toxic.
 Poor weather: Extremes of day and night temperatures.
 Stress: such as irregular watering as in tomato blossom end rot.

Control of Crop Diseases

 Cultural method: This involves use of

 Healthy planting materials.
 Practicing field hygiene.
 Proper seedbed preparation.
 Proper spacing.
 Heat treatment of the planting materials for example sugar cane.
 Proper drying of cereals and pulses to 13%M.C.
 Growing disease resistant varieties.

Legislative Method

 Involves the imposing of regulations and laws especially in case of disease outbreaks to
prevent the introduction and spread of diseases.

Chemical Control

 Used as a last resort.

 Chemical control measures include:
 Seed dressing before planting.
 Soil fumigation to control soil borne diseases.
 Spraying: application of fungicides.

Crop Production VI

(Field Practices ll)

Introduction

There are many crops cultivated in Kenya.

These crops are grown for various uses and require different ecological conditions.

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Definitions:

Hybrids —These are crop varieties developed by crossing two pure lines.

Composites - These are crop varieties developed through repeated mass selection.

Cultivars - these are varieties of crops which are cultivated in a given area.

Maize

Main growing areas: Trans-Nzoia, Nakuru, Uasin Gishu, Laikipia districts and others.

 Ecological Requirements

> Altitude: Upto 2ooom above sea level.

> Temperature: About 25°C

> Soils: Freely draining, fertile loam soils.

> Rainfall: 750-1250 mm critical at silking and pollination stage.

 Varieties

> High altitude areas: Hybrids 611, 613 and 614C.

> Medium altitude areas: 511,512,622 and 632.

> Marginal rainfall areas: Katumani composite and Makueni composite.

> Coast regions: Coast composite and Katumani composite.

 Seedbed Preparation
 Ploughing should be deep and done during the dry season to eradicate weeds.
 Require medium tilth.
 Plant spacing 75-90cm X 20-30cm.
 Planting done at the onset of the rains. This helps to reduce pest attack.
 Dry planting in areas with inadequate rainfall is necessary.
 Field Maintenance:
 Apply phosphatic fertilizer during planting at a rate of 12okg/ha P205
 Also nitrogenous fertilizers as top dress at the rate of 2ookg of ASN or CAN.
 Control weeds by cultivation, use of appropriate herbicides, uprooting, slashing and mulching.

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Pest Control

Maize Stalk Borer:

> Nature of damage: Boring the leaves causing windowing effect, boring the stems and cobs.

> Control: Destruction of previous years crop residue, closed season and apply chemicals

Maize Weevils:

> it is a storage pest.

> Damage: Bores holes into the maize grains, eating the contents.

Control: Proper hygiene and sanitation in the stores.

Use of chemicals such as Actellic Super.

Disease Control:

 Rust

> Cause: Fungus.

> Symptoms: Red or brown pustules on the. leaves.

> Control: Plant resistant varieties and crop rotation.

 Smuts

> Cause: Fungus

> Symptoms: Black sooty mass of spores on maize heads or cobs(ear).

> Control: Crop rotation, growing resistant varieties and destruction of affected plant parts.

 Maize Streak Virus

> Cause: Virus

> Symptoms: Yellow longitudinal stripes parallel to the midrib.

> Control: Certified seed, early planting and rogueing.

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Harvesting

 Harvest the crop 3-9 months after planting depending on variety.

 Maize stalks are cut and stocked in the field.
 Cobs removed by hand.
 For large scale harvesting, combined harvesters are used.
 Yields about 3,000kg and 4500kg/ha.

Bulrush Millet

Areas where grown:

 Lower areas of Kirinyaga,

 Embu,
 Meru,
 Parts of Machakos
 Kerio Valley.

Ecological Requirements

 Altitude: Does well in areas below 1200m.

 Rainfall: 500-600mm per annum.
 Soils: Light sandy soils.
 Varieties: Serere 2A, 3A, 6A, 17, 16/9

Seed Bed Preparations

 Ploughing of land during the dry season.

 Soil should be of fine tilth since the seeds are small.

Planting:

 Done at the onset of the rains.

 Planted by broadcasting and row planting at a spacing of 60cm x 15cm.

Field Maintenance:

 Weeding is done until tillering.

 Top-dressing is done by use of sulphate of ammonia.

Pest Control

Birds

 Nature of Damage: Eats the seeds at milky stage.

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 Control: Bird scaring devices.

Disease Control

Ergot

 Cause: Fungus.
 Symptoms: Heads become sticky.
 Control: Use of certified seeds, crop rotation and destruction of affected crops.

Downy Mildew

 Cause: Fungus.
 Symptoms: Long, whitish lines on the leaves.
 Control: Crop rotation and field hygiene.

Harvesting

 Done by cutting off the heads.

 Drying of the heads.
 Threshing and winnowing of the grains.
 Stored under well ventilated dry conditions.
 Yields about 1000kg/ha with good management.

Finger Millet

 Areas where grown: Western Kenya and Uganda.

Ecological Requirements

 Altitude: 0-240cm above sea level.

 Rainfall: 900mm, drought resistant in the early stages.
 Soils: Free draining fertile soils.

Varieties:

 Serere varieties developed at Serere in Uganda.

 Ultra lupin
 5.18 oats.

Land Preparations

 The seedbed should be thoroughly prepared to a fine tilth due to the small size of the seeds
 It also helps to control weeds.

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Field Operations

Planting

 Finger millet should be planted as early as possible in the season.

 It is usually broadcasted by hand.
 If planted in rows, the furrows should be 30-33cm apart and the plants should be thinned to
5cm apart within the rows.

Fertilizer Application

 Sulphate of ammonia at the rate of 125kg/ha is recommended for topdressing finger millet.

Weed Control

 Clean seedbed preparation

 Uprooting

Pest Control:

 Birds are controlled through scaring.

Disease Control

Head blast:

 Cause: Fungus
 Symptoms: Brown spots with grey centres on the leaves and stems below the inflorescence.
 Control: Use of resistant varieties.

Harvesting

 Individual heads are cut with knives.

 Heads are dried, threshed and winnowed.
 Yields 165okg/ha with good management.

Sorghum

 It is grown in Western, northern, Rift Valley, Eastern and some parts of Central Province.

Ecological Requirements

 Altitude: 0-15oom above sea level.

 Rainfall: 420-630mm. It is drought resistant.
 Soils: Fairly fertile and well drained soils.

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Varieties

 Dobbs variety.
 Serena variety.

Field Operations

Planting

 Broadcasting the seeds on the firmly prepared seedbed.

 lntercropped with other crops especially maize and beans.
 Can be planted in pure stands at a spacing of 60cm X 15cm

Fertilizer Application

 Responds well to farmyard manure (FYM).

 Inorganic fertilizers are not commonly used in growing sorghum.

Pest Control

Bird pests: They are the most common sorghum pests.

They include:

 quelea,
 aethiopica (Sudan Dioch),
 weaver birds,
 starling bird
 bishop's bird.

They are controlled through;

 killing them using explosives,

 poison spraying in their breeding places
 use of flame throwers.
 Sorghum shoot-fly controlled by early planting, closed season and application of insecticides.
 Stem borer - control by use of insecticides and field hygiene.

Disease Control

Common sorghum diseases include:

 Leaf blight
 Anthracnose.
 Sooty stripe.

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 Loose smut
 Head smut

Smuts are controlled by seed dressing-while the other diseases are controlled by growing
resistant varieties.

Harvesting

 Sorghum is ready for harvesting 3-4 months after planting.

 Heads are cut off using a sharp knife after which they are sun-dried, threshed, winnowed and
stored.
 Up to 30o0kg/hectare can be obtained with good management.

Beans

 Grown in all provinces where maize is grown.

Ecological Requirements

 Altitude: 10.00-2100 metres above sea level.

 Rainfall: Average of 625mm per annum.
 Soils: Well drained loamy soils rich in organic matter.

Varieties

Varieties for dry beans:

 Rose Coco,
 Mwezi Moja,
 Canadian Wonder,
 Wairimu,
 Haricot,
 Mwitemania.

Variety for canning: Mexican 142.

Varieties for French Beans:

 Primeur,
 Long Tom,
 Saza,
 Master Piece
 Monel.

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Seedbed Preparation

 Land should be prepared early.

 Primary and secondary cultivation done to control perennial weeds.

Seed Selection and Treatment

 Select wholesome seeds free from damage and wrinkles.

 Seeds are dressed against bean fly.
 Seeds should be inoculated with appropriate bacteria (none dressed seeds)

Planting

 Planted at the onset of the rains.

 Spacing 30-45cm x 15cm.
 Apply phosphatic fertilizer during planting time.
 Plant 2-4 seeds per hole.

Field Maintenance

 Provide sticks for the climbing varieties.

 Control of weeds through shallow cultivation.
 Top-dress with nitrogenous fertilizer for example CAN.

PestControl

Bean-Fly

> Nature of damage: Feeds on the stems causing swelling at the roots.

> This results in wilting and death.

> Control: Dressing of seeds, early planting and spraying with insecticides.

Bean Bruchid (Storage Pest)

> Nature of damage: Make dark circular windows on the grains.

> Control: Clean stores, fumigation, and seed dressing.

Diseases Control

Bean Anthracnose

> Cause‘ Fungus

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> Symptoms: Brown or black lesions on the underside of the leaves, pods and stems.

> Control: Growing resistant varieties, crop rotation, destruction of crop residues and spraying
with fungicides.

Bean Rust

> Cause: Fungus

> Symptoms: Red brown pustules on the leaves.

> Control: Planting resistant varieties and spraying copper fungicides.

Harvesting

 Done during the dry season for dry beans and when the pods are dry.
 Threshing and winnowing done.
 Sorting of rotten, off types and damaged ones.
 Sold to National Cereals and Produce Board when dry.
 For French beans, pick the pods when soft and green.
 Market immediately to avoid shrivelling.

Rice Production

Areas where grown;

 Mwea Tabere Irrigation Scheme

 Ahero Pilot Scheme in Kano plains.
 Bunyala in Busia.
 Bura in Tana River.

Land Preparation

 Plots of 0.4 hectare are made with bunds constructed around them.
 Plots are flooded for four days.
 Rotavators/jembes are used to work the flooded fields on the fifth day.
 The land is then levelled and allowed to drain.

Water Control

 During land preparation, water level should be about 7.5-10cm.

 During levelling water level should be 5cm
 Water is drained off completely for direct sowing.
 For transplanted rice, water level should be 5cm at transplanting.
 Water level should be maintained at 1/3 the height of plant until maturity.

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 Water should be allowed to flow slowly through the fields.

 Old water should be changed every 2- 3 weeks if the flow of water is not possible.
 Water introduced should always be warm to ensure pollination.

Fertilizer Application

 S.A applied in the nursery.

 Rate of 25kg SA for every nursery unit of 18.5m x 18.5m.
 Phosphatic fertilizers broadcasted in the field.
 Rate of 120kg ha DSP before planting.
 S.A applied in the field in two splits before and after transplanting at a rate of 25okg/ha

Flooding in Rice

Flood water in rice production is important for the following reasons;

 It provides good conditions for growth such as high humidity.

 Kills soil organisms.
 Prevents denitrification.

Weed Control

 Controlled through flooding.

 Appropriate herbicides such as propanil and butachlor are also used.
 Harvesting of Industrial Crops
 cotton, pyrethrum, sugarcane, coffee and tea.

Harvesting of Cotton

Stage of harvesting

 Takes 4 months to mature.

 Harvest when bolls are dry and fully opened.

Method and Procedure

 In Kenya cotton is picked manually.

 Sort out grade AR (safi) from grade BR
 (fifi) into separate containers.

Precautions

 Harvest during dry conditions to prevent dirtifying the lint.

 Avoid use of gunny bags to prevent contamination.
 Avoid picking leaves.

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 Harvest on weekly basis.

Harvesting of Pyrethrum

Stage of harvesting

 Takes 3-4 months to mature.

 Harvest the flowers with disc florets which have assumed a horizontal position

Methods and Procedure

 Pyrethrum is picked manually.

 Flowers are picked by twisting the heads so that no stem is attached.

Precaution

 Clean harvesting should be done.

 Avoid picking leaves.
 Flowers are placed in woven baskets.
 Overblown flowers are picked and thrown off.
 Pick the flowers when the dew is dry.
 Harvested flowers should be taken to the factory the same day.
 Avoid compaction of flowers in the basket.
 Harvesting interval, once in two weeks during the wet season and once in a month during the
dry season.

Harvesting Sugarcane

Stage of harvesting;

 Take 14-20 months for the plant crop to mature and 12-16 months for the ratoon crop.
 Sampling of cane is done before harvesting to ascertain the correct sugar content.

Methods and Procedures

 Cut the cane at the ground level to avoid yield loss.

 The green tops are removed from the canes.
 Harvesting matchet is used for cutting the cane.

Precaution

 Cane should be harvested immediately at maturity to avoid lowering quality.

 The green tops should be removed immediately after cutting to avoid reduction of sugar
content by enzyme invertase.

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 Burnt cane should be harvested immediately after burning to prevent rapid inversion to
monosaccharides.
 The cane should be processed within 48 hours.

Harvesting of Coffee

Stage of harvesting;

 Takes 2-4 years depending on the pruning system.

 Harvest only ripe berries.

Methods and Procedures;

 Hand picking is done so that ripe berries can be selected.

 During picking hooked sticks can be used to bend the tall trees.

Precautions

 Only the uniformly ripe berries should be picked.

 Over-ripe and under-ripe berries should be dried and sold as buni.
 Ripe cherries should be processed on the same day they are picked.

Harvesting Tea

Stage of harvesting

 It takes 2-4 years for tea to mature depending on the method of bringing young tea into
bearing.

Method and Procedures

 Tea harvesting is known as plucking.

 Fine plucking - 2 leaves and a bud are removed.
 Coarse plucking - 3 leaves and a bud are removed.
 A straight fitto(straight stick) is used to guide the plucker on the plucking table.
 Tipping is done by cutting off shoots that appear above the fitto.

Precautions

 Plucked tea is placed in woven (well ventilated) baskets to prevent fermenting before it
reaches the factory.
 The plucked tea should be kept in a cool place awaiting transport.
 It should be processed within the same day of harvesting.
 Harvesting is done on a weekly basis under wet conditions and once after every two weeks
under dry conditions.

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Forage Crops

Introduction

 Thege are plants which either grow naturally or are cultivated by man to be used for feeding
livestock.
 The term forage crops include pasture and fodder crops.
 Fodder crops are purposely grown for feeding livestock.
 They are cut or uprooted when ready
 Pasture is a round cover of grass or a mixture of grass and legumes razed directly or cut and
fed to livestock.

Classification of Pastures

 According to type of stand.

> Either pure

> Mixe_d stands.

 According to ecological zones .

> Low altitude,

> Medium altitude,

> High_altitude pastures

 According to t e establishment.

> Natura

> Artificial pastures.

Examples of grasses

 Napier,
 Rhodes,
 Setaria,
 Molasses,
 Con osi nal,
 kikuig/u, g
 star,
 Guatemala,
 Sudan

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 Guinea.

Examples of legumes;

 Lucern,
 Clover,
 Desmodium,
 Glycine,
 Stylo,
 Centrio,

Pasture Establishment

Seedbed Preparation

 This involves clearing the land, primary and secondary cultivation to a fine tilth because the
seeds are small.
 This is done during the dry season.

Selection of [planting materials

 Select see s of high germination percentage,

 Free from impurities or buy certified seeds.
 If vegetative materials are used, select from high yielding, vigorous-growing and heal y plants.

Treatment of legume seeds

 Legume seeds are inoculated with the correct strain of bacteria which fix nitrogen for crop.

Planting

 This is done at the beginning of the rains

Methods of sowing are;

 Direct sowing,
 Under sowing,
 Over-sowing

Over sowing

 This is introduction of a pasture legume in an existing grass pasture.

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Under sowing

 The establishment of a pasture in an already existing crop which acts as a cover crop.

Seeds rate depend;

 On purity o seeds,
 Pasture species
 Whether pure or mixed stand. Apply phosphate fertilizer when planting and later top-dress
with nitrogenous fertilizer.

Pasture management

 Re-Seeding or gapping; Re-seeding is done if the grass is completely denudated.

 But if partialy, gapping can be done
 Control of weeds by slashing, uprooting and mowing

Fertilization of pastures-done by use of manures and nitrogenous fertilizer.

 Topping;This is t e removal of stemmy fibrous material left behind after grazing.|t allows
newtgrowth after the rains
 Control of pests-done by trapping of moles, use of pesticides and biological means.

Pasture Utilization

 Pastures should be utilized at maturity when nutritive value is high.

It is utilized through the following methods:

 Direct grazing - this can be done through rotational grazing or herding.

 Zero grazing - this is where the pasture is cut and fed to the animals in the stalls.

Common fodder Crops

Edible Cana

 Altitude: 1500 - zooom above sea level.

 Establishment: Young tubers or bulbs are used.
 Spacing: 1m x 1m.
 Management: Does well with application of farmyard manure and requires fertile land.
 Utilization: Tops and tubers are sliced and fed to livestock.
 Conservation: Bulbs or tubers are sliced and stored.

Napier Grass

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 Altitude: 0 - 2000m above sea level.

 Establishment: Stem cuttings or splits.
 Spacing: 1 m x 50cm.

Management:

 Apply phosphatic fertilizers during planting time.

 Top-dress with nitrogenous fertilizers in split application.
 Clean weeding when young.
 Cut when 6-8 weeks or 1m-1.5m in height.
 Utilization: Cut stem is fed to livestock.
 Conservation: Ensiled when in plenty.

Types of Napier Grass:

 Bana grass (broad-leaved with hairy leaves)

 Clone (thin-stemmed and hairless)
 French Cameroon (thin-stemmed and not hairy).
 Pakistan hybrid (thin-leaved with hairy leaves).
 Used for silage making.

Lucerne

 Altitude: 1500 - 2500m above sea level.

 Soil: Deep red soil are ideal.
 Establishment: inoculated seeds are planted 30~50cm apart in the rows.
 Management: Weeding and fertilizer application.
 Utilization: Cut wilted and fed to livestock before flowering stage.
 Conservation: Hay, silage, dried materials such as cubes or pencils.

Mangolds

 ls a root crop.
 Root is utilized as livestock feed.
 Ripe ones are used.

Kales

 Leaves used as livestock feeds.

Guatemala Grass

Leaves and stems used as livestock feed.

Sorghum Grass
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Two varieties:

Columbus grass Sudan grass.

Established from seeds which are drilled or broadcasted.

Columbus grass should be dried before feeding to animals to avoid hydrocyanic and prussic acid
poisoning.

Desmodium (Desmodium spp)

Two varieties;

 Green leaf
 Silver leaf.
 Established from seeds on thoroughly prepared clean beds.
 Can also be inter~planted with Napier grass.
 Cut and wilted before feeding to livestock.

Agroforestry, trees used as fodder crops include:

 Leucaenia
 Calliandra
 Atriplex
 Sesbania.

Forage Conservation

Forage can be conserved as;

 Hay,
 Silage
 Standing forage.

importance of forage conservation:

 To reserve excess forage for use during time of shortage.

 To avoid unnecessary wastage of forage.
 Conserved forage can be sold.
 To have sustained supply of feed for livestock throughout the year.

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Methods

Hay Making

 This is the dehydration of green pastures to a moisture content of 16-20 per cent

Steps in hay making:

 Cut the crop when the sun is shining.

 Dry the materials for 1-2 days.
 Windrow the dry material to allow for further drying.
 Bale the dry materials for storage.
 Store under shed or shelter.

Factors Determining Quality of Hay

 Stage of growth at which forage is harvested.

 Leaf content of the forage material.
 Method of handling and curing the hay.
 Form in which material is fed to livestock.
 Species of forage used.
 Amount of foreign materials in forage.

Silage Making

 This is a feed produced by conserving forage in succulent form through the process of
fermentation by anaerobic bacteria.

Steps in silage making:

 Cut the crop and transport it to the silo,

 Material with a high moisture content is wilted in the sun for 4-48 hours before ensiling.
 Material is chopped to reasonable size pieces before filling in the silo.
 Spread the chopped material evenly.
 Check temperature if below 31°C, needs further filling; if above 31°C compaction is
necessary.
 Filling should be complete by the end of the third or fourth day.
 The silo is covered with 15cm of straw, sawdust then 15cm of soil to make it air and water
tight.
 A trench is dug round the silo to keep off surface water.

Factors Affecting the Quality of Silage

 Maturity stage of the crop when cut.

 Type of crop.

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 Moisture content of the material

 Additives such as molasses.
 Degree of compaction.
 Size of pieces ensiled.
 Amount of foreign materials included in the silage.
 Amount of leaf of the ensiled material.

Standing Forage

 This is forage left in the field to be used during the dry season.

Livestock Health Ill: (Diseases)

Introduction

Livestock diseases are classified according to causative agents as follows:

 Protozoan diseases -caused by protozoans.

 Bacterial diseases - caused by bacteria:
 Viral diseases - cause by virus.
 Nutritional diseases - brought about by nutritional disorders.

Protozoan Diseases

 East coast Fever (ECF).

 Anaplasmosis (gall sickness)
 Coccidiosis
 Trypanosomiasis (Nagana)

East coast Fever

 Animals attacked: Cattle

 Cause: Protozoan. (Theileria parva)
 It is a tick-borne disease transmitted by red-legged tick and brown ear tick

Symptoms

 Rise in body temperature.

 Swelling of lymph glands below the ear.
 Difficulties in breathing.
 Dullness.

Control and Prevention

 Control of vectors through dipping and fencing.

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 Treatment by use of clexon in the early stages.

Anaplasmosis (gall sickness)

Animals attacked:

 Cattle between 2 months and 2 years.

 Poultry.
 Lambs and kids.
 Rabbits.

Cause:

 Protozoan (Anaplasma marginale)

 Transmitted by the blue tick
 contaminated surgical instruments and hypodermic needles.

Symptoms

 Fever/rise in body temperature.

 Constipation or hard dung.
 Paleness in the gums, eyes and lips.
 Drop in milk production.

Control

 Tick control.
 Intramuscular injection of antibiotics and iron giving injections.

Coccidiosis

 Coccidiosis of Poultry
 Cause: Protozoan (Eimeria spp.)

Symptoms

 Sudden death of chicks.

 Whitish, yellow and blood stained diarrhoea.
 Ruffled feathers.
 Chicks become paralysed before dying.
 Chicks become anaemic and dull.

Control

 Disinfection of chick house.

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 Prevention of contamination of food and water with droppings.

 Use of prophylatic drugs for example, Coccidiostats.

Trypanosomiasis (Nagana)

 Animals attacked: cattle, sheep and goats.

 Cause: Protozoan of the trypanosome species,
 Vector-tsetse flies.

Symptoms

 Fever
 Dullness.
 Anorexia/loss of appetite.
 Loss of body condition/emaciation.
 Swollen lymph nodes.
 Lachrimation which leads to blindness.
 Diarrhoea
 Rough coat and sometimes without hair and may be cracked.
 Swelling in parts of the belly.
 Drop in milk production in lactating cows.
 Loss of hair at tail end.
 Anaemia.
 Abortion may occur in pregnant females.

Control

 Treating animals with trypanocidal drugs.

 Effective vector (Tsetse flies)control
 Confinement of wild animals in game parks.

Bacterial Diseases

 Fowl typhoid
 Foot rot.
 Contagious abortion.
 Scours.
 Blackquarter.
 Mastitis.
 Anthrax.
 Pneumonia.

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Fowl Typhoid

 Animals attacked: All domestic birds which include chicken, turkey and ducks
 Causes: Bacteria (Salmonella gallinarum}

Symptoms

 Depression/appearing very sick.

 Respiratory distress.
 Dullness.
 Drooping wings.
 Sleepy eyes.
 Anaemia resulting in pale and shrunken
 combs and Wattles.
 C-reenish yellow diarrhoea.

Control

 Killing all affected birds and proper disposal of the carcasses.

 Maintaining hygiene in the poultry house.
 Ensuring that the house is dry and well ventilated.
 Obtaining chicks from reliable sources.
 Treatment using sulphur drugs which are mixed in drinking water or mash.
 For example: application of Furazolidone (Furazol) at the rate of 0.04% in mash for 10
continuous days treats the disease effectively.

Foot Rot

 It is also referred to as foul-in-the foot.

 Animals attacked: cattle, sheep and goats.
 However, it is most serious in sheep.
 Cause: Bacteria ( F usiformis necrophorus and Fusiformis nodosus).

Symptoms

 Animal's foot becomes swollen.

 Lameness is observed.
 Pus and rotten smell come out of the hoof.
 Sheep are found kneeling while grazing when the front feet are affected.
 Animals spend most of their time lying down when the hind feet are affected.
 Emaciation due to lack of feeding.

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Control

 Hygiene in the living places.

 Regular foot examination and hoof trimming.
 Use of a foot bath of copper sulphate solution at 5-10% solution or formalin at 2-5% solution.
 Treating wounds on the feet with antiseptics.
 Affected animals should be given antibiotic injections.
 Isolation of sick animals from healthy ones.
 Avoid dampness and muddy conditions.

Contagious Abortion (Brucellosisl Bang's Disease)

 Animals attacked: cattle, sheep, goats and pigs.

 It also affects man.

Cause: Bacteria

 Brucella abortus in cattle,

 Brucella suis in pigs
 Brucella malitensis in goats and sheep.

Symptoms

 Spontaneous abortion or premature birth.

 Retained placenta if abortion occurs during the later stages of pregnancy.
 Infertility in cows while bulls have low libido and inflamed testis also known as orchitis.
 A yellowish brown, slimy, odourless discharge from the vulva may occur after the abortion.

Control

 Use of artificial insemination.

 Slaughtering affected animals followed by proper disposal of their carcasses.
 The attendant to the animals should avoid contact with the aborted foetus.
 A blood test should be carried out for all breeding animals to detect the infected ones.
 Hygiene in the animals’ houses.

Scours (white Scours)

 Animals atacked: calves, piglets, lambs and kids.

 Cause: A bacterium which attacks young animals in the first week of life.

Symptoms

 White or yellowish diarrhoea.

 Pungent smelling faeces.
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 AGRICULTURE NOTES

 Fever
 Anorexia/loss of appetite.
 Listlessness.
 Sunken eyes.
 Undigested milk and mucus with blood spots observed in the faeces.
 Faecal matter sticks to the hind quarters.
 Sudden death if no treatment is given.

Control

 Maintaining hygiene in the young animal housing units.

 Avoiding dampness on the floor of the house.
 Fingers of the attendant training calves to drink milk from a bucket must be disinfected.
 Calving should be carried out in a clean area.
 Have separate attendants for the infected calves to prevent disease spread.
 Replacing milk with warm water mixture.
 Treating affected animals with antibiotics.

Black Quarter

 It is also known as black leg.

 Animals attacked: All ruminants aged between 8 - 18 months.
 Cause: Bacteria (Clostridium chauvei and Chauvei septicum)

Symptoms

 Lameness.
 Feven
 Fast and heavy breathing.
 Cracking on the swollen parts if touched.
 Swelling of the affected parts usually the hindquarters, shoulders and chest or back
 Dullness.
 Anorexia.
 Grunting and grinding of teeth.
 Animal stops chewing cud.

Control

 Treating with recommended antibiotics.

 Vaccinating using black quarter vaccine known as blanthax.
 Burying the carcass deep or burning it completely.

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Mastitis

 ls an inflammation of the udder.

 Animals attacked: Goats, cows, pigs and human beings.
 Cause: Bacteria (Streptococcus spp. or Staphylococcus spp.)

Pre-disposing Factors:

 Incomplete milking.
 Injuries on the udder and teats.
 Weak sphincter muscles of the teats allowing free flow of milk.

Symptoms

 Milk is watery, blood stained or clotted.

 Swollen udder

Control

 Proper milking techniques.

 Treatment by use of antibiotics.
 Culling of animals which are often attacked.

Anthrax

 Attacks all domestic animals.

 Cause: Bacteria (Bacillus anthracis)

Symptoms

 Sudden death.
 High fever.
 Grinding of the teeth.

Pneumonia

Cause:

 It is an inflammation of the lungs.

 Animals attacked: Calves, kids, lambs, piglets and poultry.
 Bacteria (Mycoplasma mycoides)
 dust
 worms in the lungs.

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 AGRICULTURE NOTES

Symptoms

 Dullness.
 Anorexia/loss of appetite.
 Staring coat.
 Emaciation.
 Breathing rapidly.
 Abnormal lung sounds when breathing.
 Coughing if the chest is pressed.
 Fluctuating body temperature.
 Nasal discharge.

Control

 Keeping young animals in warm pens.

 Proper sanitation.
 Isolation of the affected animals.
 Treating using antibiotics.

Viral Diseases

 Rinderpest.
 Foot and mouth disease (FMD).
 New Castle
 Fowl pox
 Gumboro
 African swine fever

Rinderpest

 Animal attacked: Cattle and wild game.

 Cause: virus.

Symptoms

 Harsh staring coat.

 Rise in temperature.
 Eye discharge (Lachrimation)
 Diarrhoea and dysentery.
 Ulcers in the mouth.

Foot and Mouth Disease

 Animals attacked: Cattle, sheep, goats and pigs.

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 Cause: Virus .

Symptoms

 Sharp rise in temperature.

 Blisters in the mouth, hooves, udder and teats.
 Loss of appetite.

Control

 Vaccination.
 Quarantine
 nursing wounds with disinfectant.

New Castle

 Animals attacked: Poultry.

 Cause: Virus.

Symptoms

 Difficulties in breathing.
 Beaks remain wide open and necks are strained.
 Birds become dull.
 The birds stand with eyes closed all the time.
 Anorexia/loss of appetite.
 Nasal discharges which force the birds to shake their heads to clear it.
 Birds walk with a staggering motion.
 Paralysis of wings and legs may occur.
 Birds have their beaks and wings down.
 Birds produce watery greenish diarrhoea.
 Birds lay soft shelled eggs.

Control

 Killing all birds and burning them followed by cleaning and disinfecting the houses before
bringing in new stock.
 Vaccination should be done during the first 6 weeks and then 2-3 months later.
 Quarantine.

FowlPox

 Animals affected: Poultry.

 Cause: A virus known as avian fox.

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Symptoms

 Two types of fowl pox with different symptoms.

 Cutaneous type
 Diptheritic type
 The cutaneous type affects the skin and has the following signs:
 Injuries on the combs and Wattles, legs, vent and under the wings.
 Loss appetite.
 The diptheritic type affects internal membranes and has the following symptoms:
 Injuries in the inside of the throat and mouth membranes resulting in difficult breathing and
swallowing.
 Eyes and nose produces a watery liquid.
 Loss of appetite.
 Dullness.
 Emaciation.

Control

 Killing all affected birds followed by proper disposal of their carcasses.

 Vaccinating remaining healthy birds.

Gumboro

 It is also referred to as poultry AIDS.

 Animals attacked: Poultry.
 Cause: A virus known as Birma virus.

Symptoms

 The glands above the vent (bursa) become swollen.

 Drop in egg production.
 Birds develop respiratory distress.
 Loss of appetite.
 Low water intake by birds.
 Loss of immunity making the birds more susceptible to opportunistic diseases.

Control

 Vaccination.
 Administering vitamins and especially B12.

African Swine Fever

 Animals attacked: All domesticated pigs.

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 Cause: A virus known as lrido virus.

Symptoms

 Fever
 Loss of appetite.
 Depression/dullness.
 Emaciation.
 Coughing.
 Nasal discharge.
 Diarrhoea in serious conditions.

Control

 Vaccination.
 Quarantine.
 Killing all affected animals and proper disposal of their carcasses.
 Double fencing to keep wild animals away.

Nutritional Diseases/Disorders

 Milk Fever
 It is a non-infectious disease brought about by calcium deficiency in animals which have
recently given birth.
 Animals attacked: Cows, goats and pigs that have recently given birth.

Causes:

 Due to low calcium levels in the blood.

 Which leads to an increase in the magnesium and sugar level in the blood.
 Mostly occurs in high producing cows in the first few months of lactation.
 This is because these animals loose more calcium through milk secretion than they are getting
from the diet.

Symptoms

 Dullness.
 Muscular twitching causing the animal to tremble.
 Staggering as the animals move.
 Animal falls down ands becomes unconscious.
 The animal lies down on its side and the whole body stiffens.
 Body functions such as urination, defecation and milk secretion stops.
 Stomach contents are drawn into the mouth which later cause lung fever when breathing in.
 Loss of appetite.

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Treatment

 Intravenous injection of soluble calcium salt in form of calcium boro-gluconate ,60gms

dissolved in 500cc of water.
 Keeping the animal in a comfortable position on its sternum.
 Giving fresh water.

Note: The animals suffering from milk fever should not be given medicine orally for the
following reasons:

 It will not be able to swallow medicine.

 The medicine may get into the lungs thereby promoting lung fever.

Control

 Partial milking for the first 10 days.

 High yielding cows should be given rations containing phosphorus and calcium.
 Giving high doses of Vitamin D.

Bloat

 Animals attacked: Cattle and sheep.

 Cause: Accumulation of gases as a result of fermentation in the rumen.

Symptoms

 The left side is blown up.

 Sudden death.

Control

 Relieve by use of trocar and cannula.

 Chasing the animal around if noticed early.
 Drenching by use of stop bloat.
 Feeding ruminants with dry roughages during the wet season before grazing on lush pastures.

Livestock Production V (Poultry)

Introduction

 Poultry industry in Kenya has developed tremendously due to the use of artificial incubation
and brooding and easy availability of hybrid birds, both layers and broilers.
 Poultry production has become an easy source of income and food for the rural as well as the
urban communities.

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 The term poultry includes domestic birds such as turkeys, ducks, geese, pheasants, doves and
pigeons.
 Of late ostrich farming has become a lucrative activity.
 Poultry production starts with incubation of eggs.

Parts of an Egg

Parts of an Egg

 Shell

> Forms 10-12% of the whole egg content.

> Made of calcium and phosphorus.

> Protects the inner egg contents.

 Shell membrane

> Made of inner and outer membranes.

> Lining of the egg shell.

> Constitutes 1 % of the total egg content.

 Albumen (egg white)

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 AGRICULTURE NOTES

> About 55-60% of the total egg content.

> It is divided into chalaza, thick and thin albumen.

> Chalaza holds the egg yolk in position.

> Albumen serves as food for the chick.

 Yolk

> 30-33% of the total egg content.

> Supply embryo with nutrients.

 Germinal disc -The embryo which develops into a chick if fertilized.

 Vitelline membrane - Gives the yolk its round shape.
 Air sac

> Keeps the egg fresh by allowing gaseous exchange.

> Provides oxygen for the embryo

Egg Candling:

 This is the practice of determining the internal qualities of an egg by examining it against a
light source.

Procedure

 The egg is placed on a hole made on a cardboard box.

 This is called a candling box.
 A source of light is placed in the box directly under the egg.
 The observer then looks through the egg against the source of light below.
 Abnormalities on and within the egg can be seen through the translucent shell. incubation

 Involves the provision of fertile eggs with the proper condition for embryonic development.

Selection of Eggs for incubation

 Should be fertile.
 Should be of medium size about 55- 6ogms in weight.
 Should have smooth shell.
 Should be oval shaped.

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 Should not be cracked.

 Eggs should be clean to ensure that pores are open.
 Should not have abnormalities such as blood spots, meat spots and double yolk.
 Eggs should not be more than 5 days old.
 Eggs should be fresh that is collected within one week. internal egg qualities can be
determined through the egg candling process.

Methods of incubation

Natural Incubation

 This involves the use of a broody hen which sits on the eggs to provide them with conditions
necessary for hatching.
 Takes 20-21 days.
 The hen is given about 10-15 eggs.

Signs of Broodiness in Poultry

 Tendency to sit on an egg after laying.

 Moulting of the hen.
 Making some noise at the laying nests.
 Feathers are raised.
 It becomes aggressive when disturbed.
 It stops laying.

Preparation and Management of Natural lncubation

 The hen is given "China eggs" to sit on to induce broodiness.

 When broody the hen should be provided with a nesting nest or a saucershaped nest scooped
on the ground.
 The nest shall be lined with soft bedding and fertile eggs provided.
 The eggs are set in the evening or night.
 The bird is dusted to control externa parasites.
 The hen is allowed t hour outside to feed and exercise everyday.
 Broken eggs should be removed immediately.
 The hen s ould not be disturbed.

Advantages of Natural Incubation

 It is cheap.
 High hatchability.
 Low risk involved.
 Useful in small scale production.
 Less skill is required.

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 Less laborious.

Disadvantages of Natural Incubation

 Egg production is low because the hen will not lay eggs during incubation.
 It is not possible to plan when to incubate.
 If the hen dies the eggs will be destroyed.
 If the hen deserts the eggs or refuses to sit on them the farmer will incur losses.
 Only few chicks can be atched at a time by one hen.
 Diseases and parasites could easily be transmitted to the chicks.

Artificial Incubation

 This is the use of artificial device known as an incubator for hatching eggs.

Conditions Necessary for Artificial Hatching of Eggs

 Temperature - maintain at 37.5°C-39.4 °C throughout to control the rate of embryonic

development of the chick. High or low temperatures are lethal.
 Ventilation - Good air circulation.
 Carbon dioxide: oxygen ratio maintained at 0.03%:21 %.
 Relative humidity - Maintained at 60%.

> High humidity leads to marshy chicks

> low humidity the chick may stick to the shell.

 Turning of Eggs

> Done 3-4 times a day to facilitate uniform distribution of heat for uniform development of
chick.

> Turn slowly 180 ° clockwise along the axis to avoid breaking the blood vessels. > Some
incubators have automatic turning mechanism.

 Cleanliness - cleaning and disinfecting the incubator with formaldehyde solution.

Advantages of Artificial incubation

 It facilitates large scale production of chicks.

 Incubators are always ready when needed.
 Artificial incubation leads to higher egg production because broodiness in the hens is not
required, so there is more time for laying eggs.

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Disadvantages of Artificial Incubation

 High initial capital in buying an incubator.

 High level of management and attention is required.
 It is not economical for only a small number of eggs.
 High risks involved in turning the eggs.

Brooding and Rearing of Chicks

 Brooding is the rearing of day old chicks upto 8 weeks old for the layer chicks and 2 weeks for
the broiler chicks.
 For successful brooding the source of the chicks should be considered.

Sources of Chicks

The following factors should be considered:

 The reputation of the supplier (hatchery).

 Time taken by the chicks in transit.
 Proper sexing and breed identification.

Brooding

Natural Brooding

 A hen is allowed to take care of the chicks.

 She provides them with warmth and security.
 She stays with the chicks for 8 weeks and then rejects them.

Advantages

 It is cheap.
 Less labour is needed.
 Suitable for small scale.

Disadvantages of Natural Brooding

 Not possible to produce large numbers of chicks.

 The hen goes off laying during brooding time.
 Only possible when a broody hen is available.

Artificial Brooding

 The chicks are raised artificially in a structure known as a brooder until they are 8 weeks old.

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Brooder Requirements

 Temperature - should be about 35°C in the 15th week and reduced to 21°C by the 8“ week.
 Litter - wood shavings which are capable of absorbing 60% moisture without showing wetness
should be used.
 Space confinement - Done by use of hardboards which are about 25cm high and form a
circular space. A space of 1m for 25 chicks is required.
 Feeders and waterers ~ should be enough for the chicks and evenly distributed in the brooder.
 Ventilators - windows should be enough to allow proper air circulation but direct draught
should be avoided.

Types of Heaters in the Brooder

 Electric heaters - one ordinary bulb 100 watts can raise 30 chicks.
 One infrared bulb 240 watts can raise 100 chicks.
 Kerosene burners - Hurricane lamps can raise 100 chicks.
 Charcoal burners - these are specially made jikos with heat deflectors.

Brooder Management

Preparation Before Chicks Arrive

 Start 2-3 days before arrival.

 The brooder house should be cleaned to remove old litter and then disinfected.
 New litters 5-1Ocm high should be put in and covered with absorbent materials/news papers.
 Equipment should be cleaned, disinfected and tested to make sure that they are working.
 The brooder is lit about 6 hours before the chicks arrive.
 Feed and water should be placed into shallow containers.
 Brooder space should be confined with a hard board to prevent chicks straying far from the
source of heat.

Management After Arrival of the Chicks

 Chicks are placed in the brooder during the day to familiarize with the brooder.
 If chicks arrive stressed and weak they should be given glucose solution in the waterers.
 In case the heat source is charcoal burners they should be covered with wire mesh.
 Feed chicks with chick mash which is later mixed with growers mash as the chicks grow.
 Clean water should be provided and changed regularly.
 Constant attention should be given to the chicks for the first 2 weeks.
 Any vices should be checked and controlled.
 Any dead chicks should be removed as soon as seen.
 Ventilation should be used to control the temperature and humidity in the brooder.
 Constant disinfection is required at the entrance to avoid diseases.
 Brooder space should be increased as the chicks grow.

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 Debeaking should be done at 10 days old.

 Vaccination against diseases such as Gumboro after 2 weeks, New Castle at 3-4 weeks and
fowl typhoid at 7 weeks.
 Dusting to control external parasites.
 Growers‘ mash should be introduced gradually at 7 weeks old.
 Chicks are removed from the brooder when they are 8 weeks old.
 On average the chick uses about 1.5kg - 2.2kg of chick mash by the time it is 8 weeks old.

Temperature Control in the Brooder

If the brooder temperatures are low the following should be done:

 Brooder space is reduced.

 Heaters are increased.
 Ventilators are closed.

If the brooder temperatures are too high the following should be done:

 Brooder space is increased.

 Heaters should be reduced.
 Ventilators should be opened.

Management of the Growers

 The growers are birds at the age of 9 weeks to the point of lay that is at 18 weeks.
 Growers should be fed on growers‘ mash.
 By this time thefrowers should be occupying the main poultry house.
 Sick birds shoul be isolated and treated.
 A foot bath for constant disinfection should be placed at the entrance.
 Each bird is fed 115 gms per day of growers’ mash.
 Greens and soluble grit should also be provided.
 Clean water should be provided all the time (adilibitum).
 Drenching against internal parasites should be done by adding a dewormer into the water.
 Vermins should be controlled.
 Litter should be kept dry by turning.
 Vaccination should be done as required.
 Layer pullets require dimly lit house.

Management of the Layers

 Layers mash should be introduced at 18 weeks and increased gradually.

 The birds start laying at 18-21 weeks.
 The birds should be vaccinated against New Castle and fowl typhoid.
 Enough floor space roosts, feeders and waterers should be provided.

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 Each hen should be given 120gms per day of layers‘ mash.

 Clean water should be provided adlibitum.
 Eggs should be collected twice a day at noon and in the evening.
 Green leaves should be provided to keep the birds busy thus preventing cannibalism and
improve the yellow colour of the yolk.
 Grains should be given in addition to the layers’ mash at the rate of 65gms per bird per day .
 Soluble grit or oyster shells should be provided at all times for efficient digestion and strong
shelled eggs.
 Layers should be fed according to their body weight and the rate of egg production for
example a 70kg bag should feed 100 layers for 4-5 days.
 Enough laying nests should be provided at least 1 per 5 layers.
 The laying boxes should be dimly lit to reduce egg eating.
 Debeaking should be done when necessary.
 Broken eggs and dead birds should be disposed off properly.
 The non-layers and cannibals should be culled.

Management of Broilers

 Broilers are table birds kept for meat production.

 They have high growth rates or high feed conversion ratio.
 The objective is to produce a kilogram of quality poultry meat from less than two kg of broiler
feed.
 The broiler chick requires special broiler feed from day old to 4 weeks of age.
 Broiler starters’ mash or crumbs should be fed.
 This contains coccidiostat, high level of protein, vitamins and trace elements for early growth.
 From 4 weeks to 8 weeks they are given broiler follow-on mash or pellets.
 This feed contains high level of metabolisable energy to ensure a good cover of subcutaneous
fat in the finished broiler.
 From 8 weeks until slaughter finisher pellets should be given to increase the size.
 Adequate clean water should be provided at all times (adlibitum).
 High level of hygiene should be maintained to reduce mortality rate.
 Birds should be dusted with appropriate pesticides to control external parasites.
 Deworming should be done routinely.
 Vaccination against common diseases should be done.
 Dead birds should be disposed off properly.
 Broilers should be kept under deep litter system, the house should be well ventilated and well
lit.

Poultry Rearing Systems

 extensive, semi
 intensive intensive
 systems.

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The Extensive Systems

Free Range

 Birds are set free throughout the day to fend for themselves.
 Birds are confined in night shelters for the night.
 There is no supplementation.

Advantages

 Birds eat insects and green leaves therefore less feed is required.
 Cheap method.
 Cannibalism and egg eating are reduced since the birds are not crowded.
 Manure is evenly spread in the runs.
 Low labour requirement.
 Birds get plenty of exercises thus helping to keep in good health.
 No need to provide grit as birds pick it from the soil.

Disadvantages

 More land is required if a farmer wants to rear many birds.

 Birds can be stolen or eaten by predators.
 Eggs get lost in the vegetation or stolen.
 Eggs get dirty.
 Difficult to determine layers from non-layers.
 Birds get easily infected with diseases and parasites of the area.
 Breeding programme is not easy to follow.
 Birds can destroy crops where perimeter fencing is not constructed.
 Low productivity per unit area.

Semi-Intensive

Fold System

 Birds are confined in small portable structures called folds.

 A fold measures 3.5m long, 1.5m wide and 1.5m height.
 1/3 of the fold is roofed while the rest is enclosed with wire mesh.
 Birds get plenty of sunlight.
 Birds get fresh grass as the fold is moved to new grounds.

Advantages

 Manure is evenly spread in the field.

 Less feed is used because birds eat grass.

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 Reduces build up of parasites and diseases since the fold is moved often.
 Birds are protected from predators.

Disadvantages

 Few birds are kept per fold.

 It is laborious since the folds are moved from one place to the other.
 individual egg production record is difficult to keep.
 The fold does not last long because of
 high frequency of handling.
 The return per unit area of land is low.

Intensive System

Deep Litter System

 Birds are confined in a house throughout their life.

 The floor of the house is made up of litter which accumulates over time.
 Enough feeders, waterers and laying boxes are provided depending on the number of birds and
space available.
 Movable roosts and perches made of timber frames should be provided in the house
 Stress and vices should be watched closely and controlled.
 Eggs should be collected as frequently as possible to prevent dirt and egg eating.
 The house should be dimly lit.
 The floor space requirement should be 1m2 per 2-3 birds.

Advantages

 High stocking rate per unit area of land.

 Low labour requirement.
 Fast accumulation of manure.
 There is control of feeding, egg production and movement of birds.
 Safety of the birds is guaranteed from predators.
 No loss of eggs.
 Useful method when rearing breeding stock.
 Easy collection of eggs.

Disadvantages

 High incidence of cannibalism like egg eating, feather plucking and toe pecking.
 Regular cleaning of the house is not necessary since the litter absorbs the droppings.
 Pests and disease causing organisms accumulate in the litter.
 Individual records of the birds are not possible.
 May be difficult to find litter.

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 Eggs become dirty if laid on the floor.

 Feeders and waterers may be contaminated by the litter.
 The system encourages broodiness in hens.
 High infestation of diseases if the management is below standard.
 If there is a disease outbreak, it can spread very quickly throughout the house due to the
communal housintg.
 High cost of building deep litter house.

Battery Cage System

 Birds are confined in cages which are placed in the poultry house.
 The cages are made of wire mesh
 Each cage contains 1-3 birds.
 Water and feed troughs together with eggs trays are fitted along the front side of the cages.
 The floor of the cages should be slanting to allow the eggs to roll out of the cages.
 Droppings from the cages fall from behind for easy cleaning.

Advantages

 Records are easily kept therefore culling is easy.

 Birds do not become broody.
 More eggs are collected due to restricted movement of the hens and complete control of egg
eating.
 Tender meat is obtained from the culls because the muscles have not been toughened much.
 Handling is easier than in the other systems and individual attention to hens is given.
 Stocking rate is very high.
 Vices are greatly reduced.
 Eggs are clean because hens do not step on them.
 The system can easily be mechanised.
 Birds do not contaminate the food and water.
 Sick birds can be detected easily and isolated for treatment.
 Wire floors prevent re-infestation of parasitic worms and coccidiosis.
 No bullying during feeding.
 Low labour requirement.

Disadvantages

 Initial costs for cages, equipment and house are excessively high.
 Requires high level of management.
 Higher maintenance costs where automation is used.
 Birds may get fatigue due to lack of exercises thus lowering productivity.
 In case of disease outbreak, spreading is very fast.
 Birds develop bruises on combs, breasts and toes as they stick their necks out-to feed and walk
in the cages.

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 Not useful when rearing breeding stock and the rearing of broilers.
 Cannot be used for brooding young chicks.

Stress and Vices in Chicken

 Stress is a condition imposed on the birds making them disturbed and uncomfortable.
 Stress reduces production and brings about poor performance.
 Vices are habits developed by animals.
 These ariect production and health of the birds.
 Usually they are bad habits.

Cause of Stress in Poultry

 Sudden changes in routine management.

 Presence of strangers in the poultry house.
 Presence of animals and vermins.
 Too much noise.
 Constant and poor handling.
 Sudden weather changes.
 Disturbance of the pecking order.
 Overcrowding
 Poor hygiene.
 Disease and pest attack.
 Lack of food and water.

Control of Stress

 Poultry house should be kept quiet and constructed away from noise.
 Poultry house should be insulated to maintain constant temperatures.
 Parasites and diseases should be controlled.
 Change in routine management should be gradual.
 Enough feed and water should be provided.

Vices

 Feather pecking.
 Cannibalism (toe and vent pecking).
 Egg eating.

Pecking and Cannibalism

 Situation where birds peck at each other resulting in death or injury.

Effects:

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 Feather and body growth rate IS reduced.

 Loss of birds due to death may result from cannibalism.
 Culling rate is increased (economic loss).
 The appearance of the carcass is spoiled thereby reducing its market value.

Causes of Cannibalism

 Overcrowding in the house.

 High temperatures in the poultry house making the birds uncomfortable.
 Too bright light.
 External parasite infestation.
 Inadequate and incorrect feeding.
 idleness of the birds.
 C-reediness of the birds.
 Disturbances of the pecking order.
 Prolapses of the rectum which occurs once in a while.
 Bright light in the lying boxes.

Preventive Measures

 Ample spacing should be provided on the floor, feeders, waterers and laying boxes.
 Overheating should be avoided during brooding.
 The house should be dimly lit for the layers.
 Laying nests should be darkened and above the ground.
 Dusting should be done to control external parasites.
 Provide enough balanced ration.
 Birds should be kept busy.
 New/strange birds should not be allowed in the house.

Egg Eating

A vice influenced by the following:

 Presence of broken or soft shelled eggs.

 ldleness of the birds.
 Inadequate laying nests.
 Mineral deficiencies.
 Bright light in the laying nests.
 Greediness of the birds.

Preventive Measures

 Eggs should be collected regularly.

 Laying boxes raised above the ground.

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 Laying boxes should be darkened.

 Birds should be given balanced ration.
 Debeaking should be done as need be.
 Birds should be kept busy with greens.
 Birds should be kept according to age groups.
 Injured birds should be isolated and treated.

Marketing of Poultry Products

 Poultry products include eggs and meat.

Marketing of Eggs

 Eggs are delicate and perishable foods and have the highest value when fresh.

The factors considered when sorting out and grading eggs for the market include:

 Size/weight of the egg - large eggs fetch high prices than small ones. The average weight
should be about 57gms.
 Shape of the egg - The normal egg shape is oval, with a broad end and a narrow end.
 Cleanliness - Consumers prefer clean eggs.
 Colour of the shell - Brown eggs are popular with the consumers.
 Candling qualities - candling is done to determine freshness of the eggs and presence of any
other egg abnormalities.
 Shell texture - should be smooth and without cracks.

Poultry Meat

 Broilers are slaughtered at the age of 1-2.5months old with a life weight of 1.5-2 kgs.
 The birds are killed and dressed in a clean way before being wrapped in clean bags ready for
sale.
 The meat is sold in hotels and restaurants.
 Whole birds can be sold live in local markets.

Livestock Production VI (Cattle)

Introduction

 Cattle production is a widely distributed enterprise in Kenya.

 Most farming communities choose between the exotic and the’ local breeds or their crosses
depending on the environmental conditions.
 Whereas the backbone of beef industry in Kenya is made up of the indigenous animals and
their crosses, and based in the somewhat drier areas, the-dairy industry is mainly based on the
exotic breeds and their crosses and common in the wetter regions of Kenya.

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 Whatever production undertaken, the returns depend mostly on the management levels
provided to these animals.
 A productive herd starts with good management of the young stock.

Raising of Young- Stock.

 The young one of cattle is known as a calf.

Feeding Dairy Calves

 Newborn calves should be given colostrums within the first 3-5 days of their life.
 Colostrum is important for the following reasons:
 It is highly digestible.
 It contains antibiotics.
 It is highly nutritious.
 It serves as a laxative.
 It is highly palatable.
 Calves can be fed using natural method (direct suckling) or artificially/bucket feeding.

Natural Method

 In this method, calves suckle the mother directly.

Advantages

 The calf takes milk at body temperature.

 The milk is free from contaminants.
 Less problems of scouring.

Disadvantages

 Underfeeding of the calf may result.

 Cows may not let down milk in case the calf dies.
 Difficult to keep accurate production records.

Artificial/Bucket Feeding

 The calf is trained to feed from the bucket immediately after birth.

The calf is trained as follows:

 Well measured milk is put in a clean bucket.

 Index finger is inserted into the mouth of the calf.
 The head of the calf is lowered slowly into the bucket until the calf starts to drink the milk.
 The finger is withdrawn slowly as the calf continues to drink from the bucket.

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 The procedure is repeated until the calf gets used to the process.

Advantages

 Easy to keep accurate production record/milk yields of the cow.

 Possible to regulate the amount of milk given to the calf
 The cow does not need the presence of the calf in order to let down milk
 Easy to maintain high hygiene standards.

Disadvantages

 Laborious
 Calf may be given cold milk
 Equipment used and the stockman may be dirty leading to scours

Preparation of artificial colostrums

Ingredients used

 A fresh egg whipped in 0.86 litres of warm water

 Litre of warm water
 One teaspoonful of cod liver oil
 One table-spoonful of castor oil
 Note; colostrums is fed to the calves three times a day for the first 4 days of life and thereafter
twice a day.

Weaning of calves

Early weaning

 Calf is fed on whole milk up to the tenth week then it is weaned

 Calf is given milk equal to 10% of its body weight up to the 8“ week
 After 8th week, milk is reduced gradually by 1 kg until weaning
 Calf is given early weaning concentrates and soft forage

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Early Weaning Guide

Late weaning

 Calf is fed on whole milk up to the 3'd week, when milk is replaced gradually with skim milk.
 At the age of 3weeks the calf is introduced to calf pellets or pencils and green fodder
 The calf is given plenty of clean water.
 The calf continues to be given additional skim milk up to the age of 14 weeks when maximum
amount of milk is given.
 Skim milk is reduced from 14 weeks to 16 weeks when weaning is done

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Rearing of replacement stock

 The replacement stock includes young heifers and bulls which have been selected for breeding
to replace the old stock.

Management Practice

 Parasite Control-Spraying against external parasites and deworming against internal parasites.

Disease Control-Calves are vaccinated routinely against diseases such as; > Blackquater-at 4
months old.

> Anthrax and Blackquater at 6 months old

> Brucellosis - 3-8 months old (heifers).

 Castration - for male calves not selected for breeding.

 Identification - Suitable methods are used. It allows proper record keeping.
 Removal of Extra Teats ;

> These teats are known as supernumerary teats which make milking of the animal difficult.

> They are clipped off with teat clippers.

 Dehorning/Disbudding - The removal of horn buds using suitable methods.

Calf Housing

 Requirement of a Calf Pen;

 Should be clean and easy to clean.
 Be warm and dry.
 Have adequate space to allow exercise and feeding.
 Should be properly lit and allow sunlight for Vitamin D.
 Have proper drainage to avoid dampness.
 Draught free to prevent chilling.
 Be well ventilated to allow fresh air.

Types of Pens

These can be;

 permanent
 mobile/movable.

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Permanent Pens

 Have a solid floor raised above the ground.

 The floor should be slanted for drainage.
 Constructed near the milking parlour.

Mobile/Movable Pens

 Have an open floor to allow grass into the pen.

 Easily moved from one place to another to avoid soiling.
 Kept outdoors in the pastures to allow the calf to nibble on pastures.

Single Housing

 Calves should be housed singly up to the age of 3 weeks, when they are put in group pens.
 This is to avoid them licking each other and swallowing hairs which form indigestible balls.

Milk and Milking

 Milk is the white lacteal substance secreted by the mammary glands of the female mammals.

Composition of Milk

 Protein - Casein and whey.

 Fat - Butter fat.
 Carbohydrates - Lactose
 Minerals - mainly calcium and phosphorus.
 Water

Factors Affecting Milk Composition

 Age of the animal.

 Conditions of the animal.
 Stage of lactation and pregnancy.
 Completeness of milking.
 Type of breed.
 Season of the year.
 Type of food eaten.
 Physiological conditions such as diseases.

Milk Secretion and Milk Let-down

 Milk is secreted by the mammary glands which is an accessory gland of the reproductive
system.
 The mammary gland of a cow is known as an udder.
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Structure of the udder

Structure of the Udder

The udder is composed of the following parts:

 Alveolus cells - synthesize and secrete milk.

 Lobule - a group of alveolus cells.
 Lobe - Several lobules grouped together and drained by lactiferous ducts.
 Gland cistern - space where milk collects from the lobes.
 Teat cistern - A space where milk collects before emission.
 Teat -An organ which drains each quarter of the udder.

Milk Secretion

 The process of milk secretion is known as lactogenesis.

 The digested food is taken to the udder via blood vessels.
 In the udder the nutrients are carried into the alveoli cells where metabolic reactions take place
to build up these nutrients into milk.
 A hormone prolactine is secreted by pituitary gland which brings about lactogenesis.
 The milk secreted is then stored in the upper parts of the udder waiting to be released.

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Milk Let-Down

 The process of milk let-down occurs naturally when the animal is stimulated.
 Milk secreted moves from alveolar region through the ducts to the gland cistern.
 Oxytocin, a hormone secreted by the pituitary gland causes the contraction of the udder
muscles forcing the milk down the teats.
 Oxytocin hormone lasts 7 -10 minutes in the blood stream hence fast milking is important to
withdraw the milk.
 Milk is withdrawn from the teats by gently squeezing them.

Factors Influencing Milk Let-Down

 Presence of the calf.

 Presence of the milkman/milker.
 Rattling of the milk equipment.
 Site of the food/feeding the animal.
 Massaging or washing the udder.
 Sight of the milk parlour.

Factors inhibiting Milk Let-Down

 Beating the animal/inflicting pain to the animal.

 Presence of strangers and animals for example dogs.
 Poor milking techniques.
 Absence of the calf (in case the cow is used to it).

Clean Milk Production

The following factors are essential for clean milk production:

 A healthy lactating cow.

 A healthy and clean milker.
 Clean and properly constructed milking parlour.
 Clean and disinfected milking equipment.
 Proper handling of the milk after milking.

Milking Procedure

 The animals are brought near the milking parlour 15-20 minutes before milking to get into the
mood of being milked.
 Milking materials such as equipment, feeds, ropes, stools and salve are collected and placed
near the milking parlour.
 The animals are allowed into the milking stall one by one as the milking proceeds as follows:
 The animal is restrained in the stall.
 Feed is weighed and placed into the feed trough.
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 The udder is thoroughly washed, disinfected and dried with a clean cloth.
 A strip cup is used to test for mastitis on each quarter.
 Milking proceeds by squeezing the teats with the full hand. If machine milking the teat cups
are placed on the teats.
 For hand milking start with the hindquarters and finish with the forequarters.
 Fast milking should take about 8 minutes then end with stripping the udder.
 The milk is weighed and recorded.
 The animal is then released.

Dry Cow Therapy

 This is the infusion of antibiotics into the teat canal of a cow that is preparing for drying off.
 It prevents bacterial infection which leads to mastitis.

Milk Products

 Pasteurized milk - milk that is heated and cooled immediately.

 Ultra Heat Treated (U HT) - milk heated to a temperature of 130-135C, packed and then
cooled.
 Butter - Milk butterfat separated by a process known as churning.
 Cream -A layer of is: that collects at the top of the milk when left to stand.
 Cheese - Milk proteins which have been compressed.
 Ghee - Milk fat made from heating cream or butter.
 Skim milk - Milk without butter fat.

Marketing of Milk

 The Kenya Dairy Board regulates the production and sale of milk and milk products through
various Dairy Co-operative Societies.
 Processors and distributors of milk and milk products include;

o KCC,

o Brookside Dairies,

o Tuzo,

o Delamere Dairies

o Limuru Dairies.

Marketing of Beef

 Done by the following:

 Individual fanners through the local slaughter house.

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 Livestock marketing division.

 Kenya Meat Commission.
 Farmer's Choice.

Farm Power and Machinery

Introduction

. Farm power is any form of energy used in the farm to do work.

Sources of Farm Power

Human Power

. Performs light tasks.

. Quality of work produced is variable.

, Takes a long time to complete a task.

Animal Power

. Done by draught animals such as camels, donkeys, horses and elephants

. Used in land preparation and transportation.

Disadvantages

, Slow.

, Animals are liable to sickness and get tired.

, Need enough food.

Wind Power

. To pump water from boreholes.

. To winnow crops such as beans, finger millet and rice.

, Generate electricity.

Disadvantages

, Not easy to control and may not be available when needed.

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Water Power

 Irrigation.
 Grinding mills (to grind maize grains).

Disadvantages

 Difficult to use in the farm because it is not easy to control.

Biomas

This includes:

 wood or charcoal
 biogas power.

Charcoal/Wood Fuel Energy

Uses

 Provides heat for boiling water and cooking.

 Dehydrating of some crops.
 Curing of tobacco.

Disadvantages

 Exhaustible.
 It cannot be used directly in some farm operations.
 Large quantities are required.
 They are bulky hence difficult to transport.

Biogas

Uses

 Provides heat and light for cooking, boiling water and lighting.
 Produces electricity.

Disadvantages

 Only possible where there are animals under zero grazing unit.
 It is labour-consuming.
 Large quantities of dung are required.
 Cannot be used directly in some farm operations.

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Fossil Fuels

These include: coal,

 petroleumoils
 naturalgas.

Uses

 Petrol or diesel is burned in internal combustion engines to produce power.

 Kerosene is the main source of power to light rural homes.
 Natural gas is used for cooking, heating and lighting.

Electrical Power

It includes:

 hydro-electrical power (HEP),

 geothermal,
 nuclear
 power stored in batteries.
 Nuclear energy is a potential source of power which has not yet been used in the farms. Uses
of Electrical Power
 Runs stationary machines such as milling machines, grinding mills, cooling machines and
water pumps
 Supplies heat and light for operations of brooders.

Disadvantages

 Cannot be used directly in some farm operations.

 Lack of electricity in the rural areas.
 Power failures can lead to high losses.
 It is costly to install and maintain.

Solar Energy

Energy obtained from the sun.

Uses

 Provides heat and light.

 Used by all the plants in photosynthesis.
 Dehydrating crops such as vegetables, maize grains, beans and hay.
 Boils water which drives turbines to produce powerfor minor uses.

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Disadvantage

 Low concentration of energy on cloudy days.

 Expensive In collecting and concentrating equipment.
 Cannot be used directly in some farm operations.
 Requires skilled labour to install and maintain.

Tractor

 The tractor has an internal combustion engine which burns petrol or diesel to produce power
 This power is then passed to the gear box from where it is transmitted in various ways.
 The common tractor engine is a four stroke cycle engine.

The four strokes are:

 Induction stroke.
 Compression stroke.
 Power stroke.
 Exhaust stroke.

induction Stroke

 Piston moves down.

 Inlet valve opens.
 Fuel and air get into the cylinder.

Compression Stroke

 Inlet valve is closed.

 Piston moves up the cylinder.
 Fuel-air mixture is compressed.

Power Stroke

 A spark is produced at spark plug, igniting the fuel-air mixture.

 The increased pressure forces the piston down the cylinder.

Exhaust Stroke

 Exhaust valve opens.

 Piston moves up the cylinder.
 Burned fuel-air mixture expelled.

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Advantages of the Four Stroke Engines

 Produce high power which can do heavy farm work.

 Have efficient fuel and oil utilization.
 Perform a wide range of farm operations.
 Are effectively cooled with water thus allowing the production of large engine size.
 Exhaust gasses are effectively expelled from the cylinders.

Disadvantages

 Are expensive to buy and maintain

 Their use is limited in some areas;
 Tractor can only be used on flat or gently sloping areas
 Require skilled personnel and support services

The Two Stroke Engines

 Found in small machines such as mowers, motor bikes, and water pumps which do light jobs
in the farm.
 All the cycles are completed in two strokes of the piston.

These strokes are;

Induction and compression stroke

 The piston is at the bottom

 Piston moves up uncovering the inlet port
 Fuel~air mixure is drawn in
 Ignition occurs when the piston reaches the top
 Piston is forced downward compressing the mixture in the crank.

Power and exhaust stroke

 The piston is at the top

 Ignited gases produce pressure which force the piston downwards
 The piston covers the inlet port and traps fresh fuel-air mixture in the crank case
 Piston moves further down to uncover the exhaust port
 Fuel»air mixture transferred from the crankcase to the combustion chamber.

What Advantages of two stroke engine?

 Cheap to buy and easy to maintain

 Economical in fuel consumption
 Can be used in a wide range of farmland, including hilly areas

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 Can do small tasks in the farm which would be un-economical to do using the four stroke
engine

What disadvantages of two stroke engine?

 They produce less power hence cannot be used for heavy duties.
 They are inefficient in burning fuel to produce power.
 They are air cooled thus limiting the size of the engine.

Systems of a Tractor

The modern tractor has the following systems:

 The fuel system.

 Electrical system
 Ignition system
 Cooling system
 Power transmission system.

The Fuel System

 Supplies fuel to the engine.

 Categorized into two types depending on the fuel used.

These are:

 The petrol fuel system.

 The diesel fuel system
 The Petrol Fuel System

Consists of:

 Fuel tank - storage of fuel.

 Fuel filter - removes foreign particles from the fuel.
 Carburettor

> atomises fuel into spray.

> introduces fuel-air mixture into the engines.

 Regulates fuel-air into suitable proportions.

 Fuel pump - forces fuel into the carburettor.
 Delivery pipe - connects all the devices.

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Maintenance

 Cleaning the carburettor regularly.

 Cleaning the fuel filter in petrol.
 Cleaning the hole in the fuel tank cap.

The Diesel Fuel System

Consists of:

 Fuel tank - storage of fuel.

 Fuel iniection pump » pumps diesel through injection nozzles and breaks into fine spray.
 Fuel filters ~ remove foreign particles from the fuel.
 Delivery pipes - connect the various devices.

Maintenance

 Replacing the fuel filter.

 Bleeding in case air is trapped in the system.
 Cleaning the sediment bowl regularly.

Structural and Functional Differences Between Petrol and Diesel Engines

Petrol engine

 It has a carburettor
 Fuel and air are mixed in the carburettor before it gets into the engine.
 Fuel is ignited by an electric spark.
 It produces little smoke because petrol is completely burnt.
 Petrol engine is light in weight and suited for light duties.

Diesel Engine

 It has an injection pump.

 The fuel and air are mixed within the cylinder.
 Fuel is ignited by compression of air and fuel mixture in the cylinder.
 It produces a lot of smoke since the diesel is not completely burnt.
 It is relatively heavy in weight and suited for heavy duties.

Electrical System

Consists of the following:

 Battery > Converts chemical energy into electrical energy. > Stores electrical energy produced
by the running

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 Ignition circuit - provide the electrical required by the spark plugs. current that produces a
spark in the engine.
 Generator circuit - provide the electrical current that starts the engine.
 Lighting circuit - supply the electrical current required for the lighting system.
 Starter motor circuit » starts the engine.

Care and Maintenance of a Tractor Battery

 The level of electrolyte should be kept iust above the plate by topping with distilled water.
 Corroded terminals should be scrapped clean and smeared with grease.
 The battery should be tightly fixed in a box to avoid spillage and damage.
 The battery should be fitted correctly on the tractor.
 The battery should be charged regularly and periodically.
 In case of long storage the battery contents should be kept upside down.
 The generator fan belt should always be functional to ensure the battery is always charged

Ignition System

Consists of:

 Ignition - change the low voltage from the battery to high voltage current required by the spark
plugs.
 Condenser - absorbs the self-induced current in the primary circuit. > stores current for a short
time.

> passes electric current to the distributor.

 Distributor - distributes the high voltage current to the spark plugs.

 Contact breaker - Interrupts the normal flow of current in the primary circuit.

State the Maintenance practices carried on the ignition System

 The carbon deposits on the spark plug electrodes should be removed.

 The spark plugs whose electrodes are worn out should be replaced.
 The contact breaker points should be cleaned.
 The breaker points should be adiusted so that they lie between 0.3omm and 0.50mm.
 The condenser should be replaced regularly.
 The ignition systems should always be kept dry.
 Ignition wires with poor insulation should be replaced.

Cooling System

 The cooling system aims at preventing the engine from overheating which would cause piston
zeisure in the cylinder.
 Some tractor engines are cooled by air while others are cooled by water.

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State the Characteristics of Air Cooled Engines

 They are simple in construction.

 They have fins and a fan blade which assists the circulation.
 They are light in weight for they have no radiators and water jackets.

Limitations

 They get hot quickly and use heavy lubricating oil.

 The cooling is not adequate under all conditions especially when carrying heavy loads.

Water Cooled Systems

 lt consists of the radiator, water jackets, water hoses, water pump, thermostat and a fanning
mechanism.
 Wateris used to absorb heat from the engine block at a reasonable rate.

Care and Maintenance of Water Cooling system

 The water pumps should be lubricated regularly.

 Clean water should be used in the radiator and trash removed from the fins.
 All pipes should be fitted tightly to avoid blockage.
 The radiator should be filled with clean water before starting the day‘s work.
 Fan belt tension should be checked regularly and if too tight or too loose should be adjusted
accordingly.

Lubrication System

 This system is aimed at supplying oil to all parts of the engine where friction is likely to occur.

importance of Lubrication system

 It helps to increase the efficiency of the machine and reduces the rate of wear and tear of
moving parts.
 It reduces the heat created by the rubbing surfaces and acts as a seal between them.
 It acts as a cleaning agent because it washes off all the dust, dirt, soot and metal chippings
from the oil paths to the sump.

Types of Lubrication Systems;

 Splash feed type

 Force feed type
 Oil mist type

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Types of Lubricants

 SAE 10 - This is thin engine oil which gives little protection when heated.
 SAE 50 - This is thicker engine oil which is recommended for protecting the bearings.
 SAE 90 - 100 - These are transmission oils which are recommended for clutch, gear box,
wheel lubrication and ball bearings.

Note: SAE - Society of Automobile Engines.

Care and Maintenance of Lubrication Systems

 Old or contaminated oil should not be used for lubrication.

 Oil should be drained when still hot to avoid sticking on the walls of the sump.
 The oil filters should be replaced when necessary.
 The correct type of oil should be used as per the manufacturers‘ instructions. Power
Transmission System
 The function of this system is to transfer power from the tractor engine to the drive shaft, the
wheel axle, the powertake off shaft and the hydraulic system.
 The system consists of the clutch, gear box, differential and the final drive.

The power transmitted from the engine is made available for use through the following:

 The propeller shaft - it connects the gear box to the differential.

 The power take off shaft (PTO shaft) -It is located at the rear part of the tractor and rotates at
the same speed as the crankshaft of the engine.
 Hydraulic system - it is operated by the use of a lever near the drivers seat.
 It is connected to the 3-point linkage and helps to lower or raise implements mounted on the 3-
point linkages such as ploughs, mowers, planters and sprayers.
 Draw bar -It is a one-point linkage at the rear part of the tractor. -lt serves for the attachment of
trailed implements that can be used during harrowing, transportation or rolling.
 Tractor Servicing
 The aim of tractor servicing is to keep the tractor in good and efficient working conditions.
 Tractor servicing is either; > short > long term.

List the Short Term Tractor Servicing

It includes:

 Checking the engine oil daily by use of a dip stick.

 if the oil level is low, it should be added.
 The fuel level should be checked at the start of every day's work and added if necessary.
 Water level in the radiator should be checked and if possible topped up.
 The level of the electrolyte should be checked daily and topped up with distilled water
accordingly.
 Nuts and bolts should be tightened every day.

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 Lost nuts and bolts should be replaced before the day‘s work.
 Grease should be applied by use of grease gun through the nipples.
 Large sediments from the sediments bowl should be removed.
 The tyre pressure should be checked daily before the day‘s work.
 The fan belt tension should be checked to ensure that it deflects between 1.9cm and 2.5cm
when pushed.
 The brake shaft bearing should be greased.
 The brake fluid level is maintained at the recommended level.

Long Term Services

 The engine oil should be drained completely from the oil sump and replaced with new oil.
 The gear box oil should be checked and refilled as recommended.
 The oil in the differential should be replaced as recommended.
 The linkage and the pulley attachment should be greased.
 The pulley oil level should be checked and added if need be.
 The dirty oil should be removed and replaced with clean one.

Farm Machinery

Tractor Drawn implements

 These are implements which are attached to the tractor during operation.

State the two categories. Tractor Drawn implements

 One-point hitch implements;

> Are attached to the tractor at only one point that is, the draw bar.

 They include all trailed implements such as the trailers, heavy harrows, planters and rollers.
 Three point hitch implements;

> Are implements attached to the tractor at three points that is, the top linkage point and two
lower linkage points.

> They are operated by the hydraulic system.

> They include ploughs, most harrows, subsoiler, planters, mower, ridgers, sprayers and
rotavators.

Trailers

 They are one-point hitch implements.

 They are used for transportation of goods.

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 AGRICULTURE NOTES

 Small ones have two wheels while big ones have four wheels.

Maintenance

 All the moving parts should be lubricated.

 Tyre pressure should be adjusted to the correct pressure.
 Worn out tyres should be replaced.
 Loose nuts and bolts should be tightened, worn-out ones should be replaced.
 The implements should be kept under a shed during long storage.

Ploughs

 They are primary tillage implements.

 The common type of ploughs include:

> Disc ploughs.

> Mould board ploughs.

Disc ploughs

 It is made up of heavy steel concave discs of 60-70cm diameter.

Disc plough

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Parts and Functions of a disc plough

 The hitchmast:

> ls an attachment for the three point hitch.

> Made up of two side links and a top link.

> These are parts connected to hydraulic system of a tractorfor lifting and pulling

 The beam: Supports all other parts. It also adds weight for better penetration.
 Depth wheel:

> Used when driving on highway, > it also controls the depth of ploughing. > May not be present
in all disc ploughs.

 The standard or leg: Connects the discs to the beam.

 The hub: Allows the discs to rotate smoothly hence does the cutting of furrow slices.
 The scrapers: Remove the trash and mud or soil which cling to the discs,
 Disc blades: Cut and invert the furrow slices.
 Rear furrow wheel: Controls the depth of digging and stabilises the discs. Adjustment .
 The cutting angle should be adjusted at 35° - 50° from the line of travel.
 Achieved by pivoting the beam or the standard.
 Depth of digging: This is corrected by changing the height of depth wheel or adjusting
hydraulic system and adding weights. Care and Maintenance of Disc Plough
 Check for loose nuts and bolts and replace them.
 Sharpen the disc blades if blunt.
 Lubricate the rotating parts by use of oil/grease to reduce friction.
 Paint the exposed parts for example the beam/framework.
 Clean the implement at the end of each dayls work before storage.
 Store the implements in a shed.
 The unpainted parts should be coated with old engine oil to prevent rust.

Uses of a Disc Plough

Used in areas with the following conditions:

 Virgin land with many obstacles.

 Land with too much trash or tall vegetation.
 Opening up pasture land.

Mouldboard ploughs

 This primary tillage implement is suited in areas without obstacles such as stones, tree stumps,
and roots.

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 AGRICULTURE NOTES

 It gives a uniform depth of ploughing.

Mouldboard ploughs

Parts and Functions Mouldboard ploughs

 Share: This makes the horizontal cut and starts the turning of the furrow slices.
 Mouldboard: Continues the turning of the furrow slices and pulverizes the soil.
 DiSC coulter: Makes a vertical cut in the soil to separate the furrow slice from the un-
ploughed land.
 Skim coulter: Removes any trash from between the furrow slices.
 Frog: It is the part where the share, mould board and the landside are attached.
 Landside: Stabilizes the plough and absorbs the side forces created when furrow is turned.
 Shin: Leading edge of a mouldboard.
 Knife coulter: ls a vertical knife which cuts trash and earth ahead of the share.

Care and Maintenance

 Lubricate the rolling parts for example wheel bearings and disc coulter bearings.
 Paint scratched parts of the plough.
 Sharpen the share or replace if worn out.
 Check all loose nuts and bolts and replace where necessary.
 Clean the implement after each day‘s work to remove soil, mud and trash.
 For long storage, keep under a shed and apply lubricants.

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Adjustment

 Depth:

> Controlled by raising or lowering the depth wheel.

> Controlled by hydraulic control lever setting.

 Pitch: controlled by altering the length of the top link.

 Front furrow width: Controlled by cross shaft adjustment lever or by rotating the cross shaft
crank
 Lateral levelling: Controlled by tractor lift rod.

Operational differences between a disc and a mouldboard

Disc Plough

 Suitable on field with stones, roots and sturnps.

 Does not invert the furrow slices completely.
 More secondary operations are necessary after it has been used.
 Cuts at varying points.
 Not easily broken by obstacles.
 Requires less power to operate.

Mouldboard Plough

 Cannot be used on fields with stone,roots or stumps.

 inverts the furrow slices completely.
 Fewer secondary operations are needed.
 Operates at uniform depth.
 can easily be broken by obstacles.
 Requires more power to operate.

Harrows

 They are secondary cultivation implements.

 There are different types of harrows.
 The common ones are:

> disc, Harrows

> spring tine Harrows

> spike tooth harrows.

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Disc Harrows

 It comprises of a set of gangs with concave discs.

Disc Harrow

Uses

 Mixing the soil particles.

 Levelling the seedbed by breaking large
 lumps of soil.
 Killing weeds.

Disk harrows can be classified according to the arrangement of the gangs such as;

> s tandem,

> double tandem

> offset tandem.

Depth Adjustment

 Adding weights on the harrows.

 Use of hydraulic force.
 Use of light or heavy harrows.

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 AGRICULTURE NOTES

 Use of regulating wheels.

Care and Maintenance

 Check for loose nuts and bolts daily.

 Lubricate the shafts and bearings.
 Clean and oil before storage.

Spring Tine Harrow

 ls made up of flat and curved tines which act as springs.

Uses

 Levels and smoothens the seedbed.

 Breaks the soil clods.
 Mixes trash and soil thus preventing wind erosion.
 Aerates the soil.

Adjustments

 Depth is controlled by the horizontal connecting link and depth wheel.

 For individual tine, use crossbarand loosening the screws.

Care and Maintenance

 Check for loose nuts and bolts and tighten them if necessary.
 Clean after use.
 Oil the lever mechanism.

Spike Tooth Harrows

 Consists of a metal framework with rigid metal spikes which break up the soil by vigorously
hitting
 large lumps of soils as it is pulled through the soil.

Uses

 It smoothens and compacts the soil.

 It breaks big lumps of soil into small particles.
 Can be used for cultivating small crops if well set.

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Subsoilers

 Heavy and require high horse power to pull.

 Ploughing depth of 51-90cm.

Functions

 Break up compacted soil.

 Break up the harclpan.

Care and Maintenance

 Clean it after use

 Check the point and if worn out, replace it.
 Oil when not in use.

Ridger

 It is double mould board plough used to make ridges and furrows.

 It is used to prevent Water logging and draining through furrows for easy harvesting of root
crops.

Rollers

 This is an equipment used to compact the soil gently especially where tiny seeds are to be
planted.

Rotavators: (Rotary cultivntors)

 Work on the principles of high speed of revolving flail blades which beat and cut the soil
together with trash.
 It is an equipment for both primary and secondary tillage operations.
 It is driven by the P.T.O. shaft of a tractor.

Uses

 Breaks up large soil particles into small ones.

 Mixes the vegetation and the soil.
 Achieves two operations in one pass.

Adjustments

 Forward speed of the tractor gives a fine tilth of the seedbed done through the gearbox.
 Depth of work done by control of depth wheel.
 Slip clutch may break in case the knives come across obstructions

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Mowers

Uses

 Cutting grass for hay or silage making,

 cutting overgrown grass
 clearing the field.

Reciprocating Mower

Parts and Functions

 Swath stick: Keeps the cut crop falling correctly.

 Swath board: To remove the cut crop.
 Shoe: Has a runner to absorb the weight and wear.
 Cutter bar: ls a flat bar which guides the fingers.
 Wear plate: Counteracts downward force and holds the knives.

Adjustments

 To adjust knife register by moving the whole bar away or towards the yoke.
 Knife lead: The outer shoe should be adjusted to be outer than the inner shoe by 4cm.

Maintenance

 Check for loose nuts and bolts and tighten where necessary.
 Keep knife section sharp.
 Lubricate the knife parts.
 Check knife to ledger plate cup for best cutting.
 Keep all the parts tight.

Rotary Mowers

 Cutting edge consists of two blades fitted opposite to each other on horizontal disc.
 The cutting blades swing round at high speed horizontally to the ground hence cutting is
effected

Adjustment and Maintenance

 Blades should be sharp.

 Guards to be fitted around the blades to protect the operator from flying objects.
 Lubricate the P.T.O. shafts.
 Check the gear~box oil regularly and fill to the right level if necessary.

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Planters

 They are machines used for sowing seeds.

 There are two types:

> Row crop planters.

> Seed drills.

Functions of the Planters

 Meter the seed and fertilizers from seed and fertilizer hopper.
 Open the seed furrow.
 Deposit the seed in the furrow through the delivery tubes.
 Cover the seed

Functions of Parts of a Seed Plate

 Filler plate: gives proper seed depth.

 False ring: allows the seed to fall from the seed plate into the boot.
 Knockout pawl: pushes the seeds out of the cell by the roller action.
 Cut-off pawl: prevents more than one seed remaining in a plate cell.
 Cells: shaped holes to hold the seed.

Adjustments

 Adiust the coulters depth for the right crop.

 Fix the right seed plate.
 Place the planter in the level position.
 All the shafts should be free to turn.

Care and Maintenance

 Check all loose nuts, bolts and tighten them.

 Clean and oil the planter after use.
 Grease the drive sprockets regularly.

Seeders

 The grain drill sows grains of wheat, barley, oats, peas, beans and alfalfa seeds. Parts that can
be adjusted to change the sowing rate;
 Select the side of the feed wheel recommended on the drill charts for the seed-rate.
 Change the speed of the wheels by changing the gears or sprockets or both.
 Change the position of the feed gate in the cup.
 Use reducers below the feed wheel.

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Care and Maintenance

 Keep seed and fertilizer hoppers dry and clean after each day‘s work.
 Check the drive shaft and lubricate them.
 Paint the parts for example fertilizer
 hopper to be shiny

Combine Harvester

Use

 Harvesting cereal crops for example maize, wheat and barley.

 It is designed to do the following:

> Cutting

> Threshing.

> Winnowing

> Bagging

Parts of a Combine Harvester

 Cutter bar- cuts the grain head.

 Pick up reel- direct crop into the cutter bar,
 Elevator- channels the cut grain to the threshing drum.
 Winnowing ran - fans trash up onto a straw walker and directs it out of the combine harvester
 Delivery tube » delivers the clean .grains into a collecting tank from where it is bagged.

Maintenance of a Combine Harvester

 Loose nuts and bolts should be tightened.

 Remove all foreign materials stuck in the machine at the end of the day‘s work.

Ridgers

 They are used for harvesting tuber crops and for making furrows or ridges.

Maintenance

 Lubricate the moving parts.

 Clean the implement after use.
 Store undera shed.
 Repair or replace worn-out or broken parts.

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 Loose nuts and bolts should be tightened.

 Unpainted parts should be oiled during long storage.
 Shares should be sharpened if blunt.

Foragers

 They are tractor mounted and operated by power from the P.T.O. shaft.
 Used for harvesting forage crops such as Napier grass, sorghum and maize.

Maintenance

 Tighten loose nuts and bolts.

 Lubricate moving parts.
 Store in a shed.
 Clean after the day‘s work.
 Repair/replace worn out or broken parts.
 Unpainted parts should be oiled to prevent rust.

Maize Shellers

 These are stationary implements which are either hand or tractor driven.
 They consist of a rotating disc which shell maize grains from cobs.

Maintenance

 Greasing moving parts.

 Removing any stuck maize cobs.
 Repair or replace worn out or broken parts.
 Store in a shed.

Animal Drawn Implements

Ox-Plough

 Ox-plough is a simple type of a mouldboard plough which is pulled by a pair of oxen, donkeys
or camels.

Ox-Plough

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Explain the functions of the following parts of an ox-plough

 Main beam - It is the main component onto which all the other parts are attached.
 Mouldboard - It inverts the cut furrow slice upside down.
 Plough share -It cuts the furrow slices.
 Land wheel- It regulates the depth of plough.
 Draft rod - lt is on this rod that a chain is connected on which a yoke is linked.
 It forms the draught mechanism of the plough.

What are the Advantages of an Ox-Plough Over Tractor Drawn Plough ?

 Less skill is required to operate it.

 Useful where tractors cannot be used for example steep slopes.
 Cheap to buy and maintain.

What are the disadvantages of an Ox-Plough Over Tractor Drawn Plough

 Much time is wasted in training oxen.

 Tedious and laborious to the driver of the animals and the controller of the implement
 Animals can be sick or in poor physical state.
 Extra land is required as grazing fields for the oxen.

Adjustments

 Depth of plough is controlled by the land wheel and draft rod

Care and Maintenance

 Sharpen or replacing of the worn out share

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 Replacement of worn out parts such as hooks and draw bar assembly.
 Oiling the shiny parts e.g moulclboard
 Wash off the soil after use.
 Paint the handles, beam and braces to prevent rusting.

Ox-Drawn Cart

 These are small carriages harnessed to the animals by a yoke

 The small carts have only two wheels bigger ones have four.
 They are pulled by animals in singles or in pairs
 Carts are used for transport.

Maintenance

 Moving parts should be oiled

 The yoke should be repaired when worn out or replaced if not repaired
 Tyre pressure should be checked and adjusted accordingly
 Repair other damages on the cart.

Agricultural Economics Ill:

(Production Economics)

Introduction

 The agricultural sector is a key player in the economy of our country.

 It is a major employer and brings a lot of national income through foreign exchange.

National Income

 These are the total earnings from goods and services produced by a country in a period of one
year.

Relationship Between Firm and Household

 A household is considered to be a unit comprising a farmer and family members.

 It produces raw materials and consumes manufactured goods.
 A firm on the other hand, is any manufacturing or processing unit which consumes raw
materials and produces manufactured goods.
 Both household and firm generate income, which in turn, is used to: > Improve the standard of
living of the household members by paying for essential goods and services.
 The firms build more industries to create more employment and revenue through salaries and
wages. > Finance government projects through taxes and hence further national development.

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Gross Domestic Product (G.D.P.)

 This is the sum total of all goods and services produced in a country in a period of one year

Gross National Product (G.N.P.)

 ls the sum total of G.D.P. and the difference between income inflow (revenue coming into the
country from outside) and income outflow (money going out of the country by foreign
investors).
 It represents the total income earned within the country and from abroad.

Per Capita income

 ls the Gross National Income (in terms of revenue) divided by the number of people living in
the country.
 It is not a good measure of the economic well-being of the people because of the uneven
distribution of income among them.

Contribution of Agriculture to National Development

 The interaction between household and the firm generate income which is used to finance
further expansion of the firms.
 This creates more employment and revenue.
 The government taxes the income to finance national development programmes such as;

> health,

> education,

> water, energy

> communication.

Factors of Production

 A factor of production is anything that contributes directly to output, that is, it is a productive
resource.
 Productive resources usually employed in the production of goods and services. Include:

> Land

> Labour

> Capital

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> Management

Land

 As a factor of production, refers to the natural characteristics and properties of a given area of
land.
 The key factor here is productivity for example soil fertility, presence of water and minerals
and is always fixed and has no geographical mobility.

Labor

 Besides being a consumer, human beings are also a factor of production.

 They provide the labour force (human power) required in the production process.
 Labour is assessed in terms of productivity and not mere numbers of workers or labourers.
 Labour is measured in terms of man hours, man days or man months.
 The labourer's productive capacity depends on such factors as;

> age,

> health,

> state of nutrition

level of education.

 The amount of work and the efficiency with which it is performed determines the quality of
labour.

Capital

 Capital refers to all man-made assets that help land and labour to produce.
 It is categorized into:

> Fixed/durable;

> Working capital

> Liquid capital

Fixed/durable;

Capital for example

 machinery,
 buildings

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 permanent improvements on land like fences, roads,

 irrigation facilities
 water supply system.

Working capital;

Which include consumer goods such as;

 fertilizers,
 livestock feeds,
 fuel in store,
 pesticides.

Liquid capital;

For example;

 ready money,
 bank deposits,
 shares in financial institutions.

Management;

 it is a process of decision making in the farm.

 Managers use their knowledge and judgment to decide how to combine the other three
productive resources in the best way possible.
 They make plans, execute them and bear the risks or consequences which such plans entail.

Production Function

Definition

 Production function is a physical relationship between inputs and outputs in a production

process.
 It tells the quantity of output (product) that may be expected from a given combination of
inputs.
 Production function may be expressed in table form or graphically as a curve.

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Examples:

Feeding pigs for pork production at varying levels of concentrate feed.

Types of Production Functions

 A production function assumes three forms which may be treated as different types:

> Increasing Returns

> Constant Returns

> Decreasing (Diminishing) Returns

Increasing Returns

 In this type, each additional unit of input results in a larger increase in output than the
preceding unit.
 This shows that resources are under utilized.

Constant Returns

 The amount of the product increases by the same amount for each additional input; that is
constant returns to input factor.

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 Again here resources are under utilized.

Decreasing (Diminishing) Returns

 Here, each additional unit of input results in a smaller increase in output than the preceding
unit.
 Resource use is stretched to the maximum.
 It is the most commonly encountered form in agricultural enterprises;
 It gives rise to the law of Diminishing Returns.

Examples:

 Feeding dairy cows for milk production with varying amounts of feed
 Crop responses to application of varying amounts of fertilizers
 Use of varying units of labour on fixed unit of land.

Economic Laws and Principles

The Law of Diminishing Returns

 The law of diminishing returns states that;

"if successive units of one input are added to fixed quantities of other inputs a point is
eventually reached where additional product (output) per additional unit of input
declines.”

 This law is encountered practically in all forms of agricultural production

 It is useful in determining the most rational and profitable level of production

Example:

Production of maize at varying levels of N.P.K. fertilizer application on a fixed area of land

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Zones of a production function curves

Zones of a production function curves these are:

> Irrational zone or Zone I.

> Rational zone or Zone II

> Irrational zone or Zone III.

 The three zones are arrived at by drawing two perpendicular lines through the production
function curve, one at MP = AP and another at MP=O.
 In Zone I resources are not fully utilized while in Zone III, excessive application of resources
leads to production decline or loss.
 It is not economical to produce at these levels.

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 In Zone II resources are maximally utilized resulting in maximum production.

 It is therefore economical (or wise) to produce at this level.

Principle of Substitution

 States-"if the output in a production process is constant, it is profitable to substitute one

input factor for another, as long as it is cheaper than its next alternative."
 This principle is applicable in a situation where more than one variable input factors are used.
 For example feeding hay and concentrates for milk production, farmyard manure and
phosphatic fertilizers in the production of maize.
 The basic problem that the producer wishes to solve when two input factors are used in
combination is in what proportions must the variable inputs be combined in order to produce at a
minimum cost and hence attain maximum profit.
 To solve the above problem, the producer must determine the least cost combination of inputs
used.
 The least cost combination is attained at a point where the Marginal Rate of Substitution
(MRS) equals the inverse of price ratio of the factors involved.

That is:

A X2:PX1 A X1= PX2

X1 - first input factor

X2 second input factor

A» change (increase or decrease)

P - price (cost of input fators)

Examples:

 Producing 20 bags of maize using varying combinations of farmyard manure and phosphate
fertilizers.
 Price of farm yard manure (FYM) is KShs10/- per unit and that of phosphate fertilizer is Kshs
50/- per unit

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In the above example, the following assumptions are made

 A fixed quantity of output is to be produced.

 Input factors in combination substitute for one another at varying rates.
 Relative prices of input factors do not change drastically during the period of production.

NOTE: one input factor substitutes for the other at diminishing varying marginal rate of
substitution.

Principle of Equimarginal Returns

 This principle states ;" That the last unit of an input factor spent in one enterprise yields a
marginal return exactly equal to the marginal return earned from the last unit invested in each of
the other enterprises."

Example

 If the last shs.100/- spent buying cattle feed will return more than shs.100/= spent on buying
fertilizer for growing maize, then it is advisable to purchase more feed up to a point where the
last shs.l00/- spent on it will return exactly the same as the last shs.1oo/- spent on fertilizers.
 This concept is only relevant in a situation where farmers do not have adequate capital to
employ inputs up to the level where marginal revenue equals the marginal cost.

The principal of Profit Maximization

 The profit is defined as the difference, in monetary terms, between the total returns (income)
and total costs (expenses) in a production process.

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 Profit maximisation aims at obtaining the highest returns at a minimum cost per unit of input
factor used.
 This can be done by considering two concepts. Marginal Concept
 Profit is maximised when the marginal (additional or extra) revenue (MR) is equal to, or
slightly higher than, the marginal cost (Mc).
 At this point every added input factor brings in higher returns than the expenses incurred in
investing it.

Net Revenue Concepts

 Profit is said to be maximized in a production process when the Net Revenue (differences
between total revenue and total costs) is the highest that is; NR = TR - TC.
 This is arrived at by analyzing the total cost and total revenue earned from a particular
enterprise and then subtracting the former from the latter.

When calculating the profit using whatever concept, the following assumptions are made:

 Cost of inputs (such as fertilizers, labour) remains constant during the period of production.
 Price of the produce (product) remains unchanged.
 Fixed costs are ignored that is only varying costs directly involved are considered.

Farm Planning

 Planning is the process of establishing the organizational objectives and defining the means of
achieving them.

Factors to consider in drawing a farm plan.

 Size of the farm.

 Environmental factors.
 The current trends in labour markets.
 Farmer's objectives and preferences.
 Possible production enterprises.
 Existing market conditions and price trends.
 Availability and cost of farm inputs.
 Government regulations/policy.
 Security.
 Communication and transport facilities

Farm Budgeting

 Farm budgeting is the process of estimating the future outcomes of a proposed farm plan,
 That is; the future incomes and expenses of a farm plan.

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Importance of Farm Budgeting

 It helps the farm in decision making.

 It helps the farmer to predict future returns that is planning ahead.
 helps the farmer to avoid incurring losses by investing in less profitable enterprises.
 helps the farmer to secure loans from financial institutions such as Agricultural Finance
Corporation and commercial banks.
 It ensures a periodic analysis of the farm business.
 It acts as a record which can be used for future reference.
 It pinpoints strengths or weaknesses in farm operations.

Types of Budgets

Partial Budget

 It represents financial effects on minor changes in a farm organisation.

 It is necessary when a farmer wants to replace or reduce enterprise.

Complete Budget

 A complete budget is necessary when the farmer wants to start a new business where both the
variable costs and the fixed costs are likely to be affected.
 It involves a major change or reorganization in the farm business.

Agricultural Services Available to the Farmer:

 Agricultural production efficiency is greatly increased by services rendered to the farming

communities by;

> Government institutions

Non-governmental organizations.

Some of these services are:

> Extension and Training:

> Banking Services:

> Credit:

Extension and Training:

 In the field and in farmer's training centres.

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Banking Services:

 These enables the farmers to save some of their farm income and invest them in future
projects.

Credit:

 Credit is a financial assistance advanced to agricultural farmers to finance their farm projects
and repay it with interest.
 It is a borrowed resource.

Types of Credit

 Credit is categorised according to;

> Time of repayment

> The types of projects to be financed.

Examples are:

Short-term Credit

 Repayable within one year and is advanced for the purchase of;

> seeds,

> fertilizers,

> animal feeds.

Medium-term Credit

 Repayable within 2 - 5 years and is used to finance projects such as;

> fencing materials,

> purchase of livestock,

> light farm equipment.

Long-term Credit

 Repayable period is up to 15 years and even more.

 It is given for the long-term or durable projects such as;

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 AGRICULTURE NOTES

> purchase of land,

> construction of soil and water conservation structures, farm buildings,

irrigation projects for perennial cash crops for example;

* coffee,

* farm machinery

* implements.

Sources of Credit

 Co-operative societies and unions.

 Crop boards.
 Commercial banks.
 Agricultural Finance Corporation.
 Insurance companies.
 Individual money lenders.
 Settlement fund trustee.

Artificial insemination Services:

 Provides farmers with semen from improved or superior bulls to improve their livestock herds
through controlled breeding.

Agricultural Research Organization

 These develop and pass on to farmers, improved production techniques as well as crop and
livestock species with better performance in different ecological zones.

Marketing Outlets

 These are agencies that ensure effective and efficient conveyance of farm produce to points of
processing and consumption.
 They are largely crop marketing boards or corporations and cooperative societies.

Veterinary Services

 In the field are veterinary officers who help the farmer in treating and controlling livestock
diseases and parasites.

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Farm input Supplies

 Farmers are able to obtain their farm inputs from organizations such as co-operatives and
private companies.
 These organizations bring inputs closer to the farmers for example Kenya Farmers Association
and private agrovets.

Tractor Hire Services

 This involves hiring of tractors and machinery at a cost by farmers who are not privileged to
own their own.

Sources

 Ministry of Agriculture
 Private contractors.
 Individual farmers.
 Other service providers.

Risks and Uncertainties in Farming

 Uncertainty-is the state of not knowing about future events or outcomes.

 Risks-is the difference (divergence) between the expected and the actual outcome.

Types of Risks and Uncertainties

 Fluctuation of commodity prices.

 Physical yield uncertainty.
 Ownership uncertainty.
 Outbreak of pests and diseases.
 Sickness and injury.
 New production technique.
 Obsolescence for example machinery may become outdated or obsolete within a short time.
 Death of either farmer or livestock.
 Natural catastrophies such as; > floods, > drought, > earthquakes, > storm and strong winds
which may destroy crops or kill the animals.

Ways in Which Farmers Adjust to Risks and Uncertainties

 Diversification.
 Selecting more certain enterprises.
 Contracting.
 Insurance.
 Input rationing.
 Flexibility in production methods.

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 Adopting modern methods of production. Agricultural Economics IV:

(Farm Accounts)

Introduction

 Financial and physical records if accurately kept in the farm serve as very important tools in
decision-making.
 The records are kept in several books and statements as follows: Financial Documents
 They include:
 Invoices.
 Receipts.
 Delivery notes
 Purchase records.

An Invoice

 This is a document issued by the seller to the buyer for goods taken on credit, and payment to
be done later.
 The original is given to the buyer and duplicate retained by seller.
 The invoice shows the following:
 The buyer and seller.
 Date of transaction.
 Amount involved.
 Invoice number.

A Receipt

 This is a document issued by the seller to the buyer when cash payment for goods delivered is
made.
 it shows the following:
 The buyer and the seller.
 Date of transaction.
 Amount involved.
 Serial number

Delivery Note

 It is a document which shows that the goods have been delivered.

 The receiver verifies the goods and then signs on the delivery note.

Features:

 The delivery note shows the following:

 Goods delivered as per order.
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 Quality or condition.
 People involved in the transaction.
 Date of delivery.

Journal:

 It is a book of first entry showing a record of all business transactions arranged in the order in
which they occur.
 Its pages are divided vertically into five sections.
 The information is posted to the ledger

Inventory:

 This is a list of all the possession/assets item by item and their market value.
 Such items are land, livestock, tools and equipment and crops in the store.
 Valuation is an estimation of the value of each asset or item, based on market price or cost of
production.

Local Purchase Order:

 Issued by the purchasing officer of the supplier for example school.

 It shows people involved in the transaction, types and amounts of goods ordered and dates.
 It should be written and signed by the authorised officer.
 It is written in duplicate and the original is given to the supplier.

Financial Books

Ledger:

 ls a book which contains individual accounts.

 It is a principle book of accounts in which entries contained in all the other books are entered.
 It is a storehouse of all the transactions.
 Each page is numbered and vertically divided into two equal parts namely credit and debit.
 Each part is further sub-divided into four sections.

Cash Book:

 It is a book where transactions involving cash or cheque payments are recorded.

 It involves cash or cheque payments and receipts.
 It is divided into two parts - debit and credit side.
 All the receipts of cash or cheque are recorded on the debit and all payments are recorded on
the credit side.

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Example: Enter the following entries in the cash book.

 1.7.05 -Received shs.2,000 from Ndete by cheque.

 2.7.05-Bought D.A.P. fertilizer and paid cheque of shs. 5,000.
 3.7.05-Received shs.5,000 cash from Ngala.
 4.7.05 -Paid water bill for shs 400 in cash.
 9.7.05-Paid telephone bill of 1,500 by cheque.
 11.7.05 -Deposited shs.2,000 in the bank.
 20.7.05 -Withdrew shs.2,000 from the bank for home use.

Cash Book record

Financial Statements

Cash Account Sheet

 It involves the recording of sales and receipts, purchases and expense.

 Each sale or purchase is entered twice, once in the total column and once in the analysis
column.
 The sum of all the entries in the total column should always equal the sum of the entries in all
the other columns.
 The cash analysis account sheet is given above.

The Balance Sheet

 It is a financial statement of assets and liabilities recorded on a given date.

 It shows the financial position of a farm business at a glance (snapshot).

Assets are items owned by the farmer,

These include:

 Property (money, goods and buildings).

 Debts receivable from other people.
 Goods and services paid for in advance.

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Assets can be divided into two:

 Fixed assets: assets of permanent nature and not easily converted into cash.
 Current assets: assets which can be easily converted into cash.

Liabilities are claims to the farmer's property such as bank overdraft and debts payable.

They are divided into:

 Current liabilities - debts which must be paid within a short time.

 Long term liabilities - debts which are payable over many years or over a long period.Profit
and Loss Account
 Prepared at the end of a calendar year.
 It is a final account which summarises the sale and receipts (income flowing in the business)
and the purchases and expenses (flowing out of the business).
 Note: If assets are more than liabilities then the balancing factor is net capital (in the liability
side) hence the farm business is said to be solvent.
 If the liabilities are more than the assets, then the balancing factor is a loss (in the asset side)
hence the farm business is insolvent.
 To calculate profit or loss, account, valuation is done by having an inventory of all the assets.
 Valuation of the assets is determined by market price and cost of production for machinery
and buildings as depreciation factor, is attached.

Format of a balance sheet

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Agricultural Economics V

(Agricultural Marketing and Organizations)

Introduction

 Agricultural marketing is an economic activity which involves the distribution of farm

produce from the farm to the consumer.

Market and Marketing

 Market is an institution for the exchange of goods and services or a place where selling and
buying of goods takes place.
 Marketing refers to the flow of goods and services from the producer to the consumers.

Marketing Functions

 Transportation - Movement of goods from production centres to the consumption centres.

 Buying and selling - Purchase of goods from the producer to be sold to the consumer.
 Storage - Agricultural products are seasonal hence storage is necessary.
 Processing-Changing of raw form into utili sable form.
 Grading and standardisation - Sorting into uniform lots of certain qualities.
 Assembling - Collecting the farm produce from the farm to the market centres.
 Collecting market information — To know the prices, supply and demand of certain
commodities.
 Advertising - Making the consumers aware of the produce.
 Bearing of risks - Such as fire risk, price fluctuation.
 Financing or expenditure on other processes.
 Packaging or putting into small packs and labelling.
 Packing or putting produce In containers such as bags.

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Marketing Agencies and Institutions

 Middlemen (itinerant trader) - are the people who buy from the producer and sell to other
agencies.
 Wholesalers - Buy in bulk and sell to the retailers.
 Retailers - Buy from the wholesalers and sell in small units to the consumers.

Problems in Marketing Agricultural Produce

 Farm produce are bulky, that is weight and volume are high but low in monetary value thus
difficult to transport.
 Most of the agricultural products are perishable for example milk, vegetables and fruits.
 Storage problems (since they are bulky they require a lot of space).
 Lack of proper transport system since agricultural products are in the rural areas and the
market are situated in urban centres.
 Lack of market information hence farmers are exploited by middlemen.

Price Theory

 Price is the amount of money paid in exchange for goods or services.

 Price theory is concerned with the determination of price of any commodity.
 Price is determined where demand for and supply of any commodity are equal to each other.

Demand

 It is the quantity of any commodity which is purchased at any price within a given time.
 The law of demand states that quantity demanded changes inversely with the price.

Demand Curve

 The curve slopes from left to right downwards.

 This means people buy more at lower prices and vice versa.

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Demand Curve

Factors Affecting the Demand of a Commodity

 Population
 Income of the consumer.
 New inventions.
 Taste and preference of the individual.
 Price of the substitute commodities.
 Price expectations.
 Advertisement.
 Culture and social values ofthe consumers.
 Price of commodities having joint demand for example tractors and diesel.

Elasticity of Demand

 It is the responsiveness of demand to a change in price.

 Elasticity of demand : Percentage change in quantity demanded

Percentage change in price

Types of Elasticity of Demand

 Elastic demand is one where the ratio is more than 1.

 Unitary elasticity is one where the ratio is equal to 1.

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 Inelastic demand is one where the ratio is less than 1.

Supply

 Supply is the quantity of any commodity which is offered for sale at any price at a given time.
 The law of supply states that when price rises, quantity supplied increases and when price falls
quantity supplied decreases (other factors held constant).
 The curve rises from left to right upwards.
 This means that people are willing to offer more for sale at higher prices.

Factors Affecting Supply of a Commodity

 Number of sellers
 Price of substitute commodities.
 New technology.
 Price expectation.
 Peace and security.
 Weather conditions.
 Policy of the government.
 Cost of production of the commodities

Elasticity of Supply

 This refers to the rate at which quantity supplied changes due to a change in price level

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 Elasticity of Supply: percentage change in quantity supplied divided by percentage change in

price

Type of Elasticity of Supply

 Elastic supply one where the ratio is more than 1.

 Unitary elasticity of supply is one where the ratio is equal to 1
 In elastic supply is one where the ratio is less than 1.
 One of the problems of agricultural produce is that supply does not readily adjust to price
changes.

Equilibrium Price

 ls the price at which demand and supply are equal.

 That means whatever is offered for sale at the market is bought
 In the graph below, the quantity supplied and demanded are equal at a price of Shs.300 and
quantity of 80kg.
 At this point the price is higher than shs.300 then the supply will be greater than demand and
there will be surplus hence price will fall.
 If, on the other hand, the price is less than shs.300 demand will be greater than supply hence
shortage and rise in price.

Agricultural Organization

 Agricultural organizations are agencies which, through their activities, promote agricultural
development.
 These organizations are co-operatives and statutory boards.

Co-operatives

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 A co-operative is an organisation of people with a common aim of pooling their resources to

achieve their objectives.

Functions of Co-operatives

A co-operative society carries out the following functions:

 Collecting and assembling members’ produce.

 Processing the farm produce after collection.
 Transportation of members’ produce to market points.
 Negotiation of fair prices with the purchasing agencies for the members’ produce.
 Purchase and distribution to members of farm inputs.
 Storage of members’ produce before transmission to market points.
 Provision of credit facilities to members on easy terms.
 Training and education of members on improved farming techniques.
 Offering farm machinery services to their members on hire terms for farm operations.
 Co-operatives may invest in other viable ventures and the profits realised are shared among
members in form of dividends or bonuses.

Formation and Structure of Co-operatives

The formation of a co-operative takes the following stages:

 Individuals with common interest collect together to form a primary co- operative society
 At least ten (10) members qualify for registration.
 Each primary co-operative society elect their office bearers consisting of chairman, secretary
and treasurer.
 Several primary co-operative societies are usually amalgamated to form a district co- operative
union.
 Tertiary co-operative unions are nationwide organizations to which the secondary co-operative
unions are affiliated.
 Examples are Kenya Planters Co-operative Union, Kenya Farmers Union, Kenya Co-
operative Creameries, Co-operative Bank of Kenya, etc.
 Apex organizations. This is represented in Kenya by Kenya National Federation of Co-
operatives which is an affiliate of the International Co-operative Alliance. Problems Facing Co-
operatives

Co operatives encounter the following problems in their operations:

 Managerial problems arising from:

 Financial mismanagement due to poor accounting. > Corruption and misappropriation of
cooperative resources by the personnel in the system.
 Lack of advisory services on technical operations.

> Inability to meet the set obligations of providing credit facilities due to malpractices.

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 The nature of agricultural products and associated problems.

> Bulkiness hence difficulties in transportation and storage.

> Perishability of produce hence difficult to sustain quality.

 Inadequate capital to invest in the cooperative undertakings.

 Transport problems due to poor roads.

> This hampers the produce getting to the market points in time.

Statutory Boards .

> A statutory board is an organization established by an Act of Parliament and charged with the
running or managing of a certain industry within the government sector.

Marketing Boards

 Some of the statutory boards are charged with the marketing of certain farm produce and are
thus called marketing boards.
 Examples are the Coffee Board, Pyrethrum Board, Cotton Seed and Lint Marketing Board,
Tea Boards, National Cereals and Produce Board, Kenya Meat Commission, the Dairy Board of
Kenya and others.
 Their marketing functions are to look for market and better prices.

Research Organization

 These are research centres which among other things, carry out research and trials on:
 Development of new varieties and cultivars of crops.
 Breeding disease and pest resistant varieties of crops and types of animals.
 Adaptations of crop and livestock species to ecological conditions of certain areas.
 Use of fertilizers and pesticides on crops in specific areas.
 Development of early maturing and high yielding species.
 Soil testing and crop analysis. Advisory services of agro-economic aspects.

Other Organizations

Kenya National Farmers‟ Union negotiates for:

 Reasonable and affordable prices of farm inputs.

 Better prices for farm produce.
 Better credit facilities.
 Better control of diseases and pest.

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Agricultural Society of Kenya

 Organizes agricultural shows in the country.

 Encourages improvement of livestock through exhibitions and educating farmers
 Organizes the running of young farmers’ clubs.
 Organizes and finances the ploughing contests during which farmers learn the modern
techniques of seedbed preparation.
 Publish "Kenya Farmers" magazines.

Young Farmers and 4-K Clubs.

 These are student organizations whose objectives are:

 To expose the young students and encourage them to appreciate agriculture as a profession in
their career.
 To encourage the youth to develop leadership qualities through assignment of small farming
projects.
 Organizing students exchange programmes with other club members both locally and abroad.
y
 To develop better farming skills through judging competitions, annual rallies and camps.

Agricultural Based Women Groups

 These are self-help groups whose objective is to uplift the economic status of their members
by carrying out agricultural related activities.

Their success depends on the following factors:

 Commitment of their leaders.

 Motivation of the members.
 Sacrifice for each other.

Agroforestry

Introduction

 In Kenya land use is changing from extensive methods of farming to more productive and
sustainable intensive methods.
 Agroforestry is a method of farming which has become increasingly important.

Definition

 This is the practice of integrating a variety of land use

 It combines tree growing, pasture and crop production practice on the same piece of land to
improve the output of the land.

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Forms of Agroforestry

 Agroforestry;

> It is a combination of trees/shrubs and crops in agricultural production.

 Silvopastoral:

> It is a combination of growing tree/shrubs, pastoral and keeping of livestock.

 Agrosilvopastoral:

> It is a combination of growing trees/shrubs, animals, pastures, and crops.

importance of Agroforestry

 Environmental protection.
 Source of income.
 Afforestation for timber production.
 Maintenance of soil fertility.
 Aesthetic value.
 Labour saving in firewood collection.
 Source of food and feed.
 Source of fuel wood.

important Trees and Shrubs for Particular Purposes

 Eucalyptus Spp;

> Timber,

> Bee forage,

> Fuel wood,

> Medicinal,

> Production of essential oils.

 Acacia Spp;

> Leaves and pods eaten by animals,

> Provision of shade.

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 Caianus cajan (pigeon peas);

> Proteinous feed for human,

> Used as fodder

> Firewood.

 Croton megalocarpus(croton);

> Fuel wood timber for poles

> Handles for hand tools.

 Erythrina abyssinica (flame tree);

> Wood carvings,

> Bee forage,

> Nitrogen fixation

> Medicinal.

 Markhamia lutea (markhamia tree);

> Timberfor construction,

> Shade,

> Soil protection,

> Bee forage.

 Grevillea robusta (silky oak.)

> Timber,

> Fuel wood,

> Fodder

> Bee forage,

> Soil protection,

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> Wind breaker

> Shade.

 Sesbania sesban (sesbania);

> Fodder,

> Nitrogen fixation,

> Shade,

> Fuel wood.

 Calliandra calothyrsus (calliandra);

> Fuel wood,

> Fodder

> Nitrogen fixation,

> Shade,

> Bee forage.

 Persea american (avocado) ;

> Fodder

> Fruit production,

> Shade,

> Fuel wood.

 Mangifera indica (mango);

> Fruit production,

> Shade trees,

> Wind break,

> Soil protection,

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> Fuel wood.

Characteristics of Agroforestry Tree Species:

 Fast growth rate.

 Trees
 Deep rooted.
 Nitrogen fixation ability.
 By-product production ability.
 Be multipurpose in nature.
 Should not possess competitive ability with main crop ..
 Have coppicing and lopping ability.
 Have appropriate canopy - should not shade others.
 Nutritious and palatable.

Trees and Shrubs to Avoid at Certain Sites and Reasons

 Eucalyptus Spp.-should not be planted near water sources because it would absorb the water.
 Eucalyptus Spp. -should not be planted on the arable land as the roots have allelophathic
effects on other vegetation including crops.
 Tall trees should not be planted near farm buildings because they may fall and damaging the
buildings, their roots will break the building stones gradually.
 Bushy trees or shrubs should not be near farm buildings as they may harbour predators.
 Tall trees planted with main crop of a lower canopy intercept the rainfall, affecting the growth
of the main crop.
 Cypress trees have leaves which produce acidity in the soil preventing undergrowth beneath
the tree.
 These trees should not be planted within the farm but at the periphery.

Tree Nursery

 Tree nurseries are structures used to raise tree seedlings until they are ready for transplanting.
 There are 2 main types:

Bare root nurseries:

 These are also known as 'Swaziland' beds where the seedlings are raised directly into the soil.

Advantages

 Cheap and less time consuming.

 Require less labour
 Occupy a small space.
 Many seedlings are raised in a small space.
 Transportation of seedlings is easy. Disadvantages
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 Root damage when uprooting the seedlings.

 Difficult to transport.
 Lower survival rate after transplanting.

Containerized nursery:

 The seedlings in this type of nursery are raised in containers such as pots, polythene bags or
tubes and tins.

Advantages

 Higher survival rate after transplanting.

 No root damage.
 Successful in arid areas.

Disadvantages

 Labour intensive.
 Difficult to get containers.
 Sometimes it may be difficult to get the right type of soil to use in the containers.

Seed Collection and Preparation

Seed Collection

Seeds should be collected from;

 Adaptable trees,
 High yielding,
 Heakhy
 Resistant to pests /diseases.
 The mother plant should be identified first.

The following methods used to collect seeds.

 Shaking the tree.

 Gathering from under the tree.
 Lopping of the tree.
 Climbing on the trees.
 Hooking method.

Seed Preparation

 This done when seeds are collected from a fresh fruit, they should be soaked in water, then
washed and dried.

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 Cleaning and sorting: done to remove immature seeds, rotten seeds, broken or damaged seeds.
 Drying: Done by sun-drying or oven drying.
 Seed testing: this determines;

> Seed quality for percentage purity,

> Seed weight,

> Moisture content,

> Germination percentage.

 Seeds should be stored in dry containers at roorn temperature.

 Seed treatment: seeds are treated first to break the seed dormancy and ensure rapid
germination;

> Hot water treatment: used to soften the seed coat to make it more permeable to water.

> Exam_ples of seeds which require this treatment are leucaenia, calliandra and GCCICIG.

> Mechanical breaking: done by nicking the seed coat with a knife for easy entrance of water for
example seeds of croton trees.

> Light burning: applied to the wattle tree seeds.

Nursery Management

The following are the practices carried out in the nursery when the seedlings are growing:

 Mulching:

> Aim is to reduce excessive evaporation,

> Moderates the soil temperature,

> When it decays it improves the soil structure,

> Reduces the impact of the raindrops.

 Weeding:

> Done to reduce competition for growth factors by uprooting the weeds,

> Use a sharp pointed stick.

 Watering:
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> Done by use of a watering can

> Done twice a day in the morning and in the evening.

 Pricking out:

> It is the removal of seedlings in an overcrowded area to another nursery bed,

> This allows the seedlings to grow strong and healthy.

 Root pruning:

> It is the cutting of the roots longer than the pots.

Root pruning is done for the following reasons;

> Make lifting easier

> Encourage fast establishment.

> Reduce damage to the seedlings.

> Encourage development of a short dense and strong rooting system.

 Shading:

> Done to reduce the intensity of sunlight .

> Dark conditions should be avoided.

 Pest and disease control:

> Use of appropriate chemicals,

> Sterilization of soil through heat treatment,

> Fencing to protect seedlings against animal damage.

 Hardening off:

> It is the practice of preparing seedlings to adapt to the ecological conditions prevailing in the
seedbed.

> It involves gradual reduction of shade and watering 1-Zweeks before transplanting.

 Transplanting:

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> The practice of transferring seedlings from the nursery bed to the main field where they grow
to maturity.

Procedure of Transplanting

 Holes are dug early before transplanting.

 Topsoil is mixed with compost manure.
 The seedlings are watered well a day before transplanting.
 The seedlings are removed from the nurseries carefully with a ball of soil for the bare root
seedlings and roots trimmed for the containerized seedlings.
 The seedling is placed in the hole at the same height it was in the nursery.
 The container is removed carefully.
 The soil is returned into the hole and firmed around the seedling.
 The seedling is watered and mulched.

Care and Management of Trees

 Protection:

> From damage by animals such as goats and cattle by eating the leaves.

> It is done by fencing the fields or using small poles around each seedling with or without wire
nettings, can be done for individual trees or an entire field.

 Pruning and trimming:

> Pruning is the removal of extra or unwanted parts of a plant.

> The unwanted part may be due to breakage, overcrowding, pests or disease attacks and over
production.

> Pruning initiates growth of shoots and trains the tree to have the required shape.

> Regular cutting back of the trees is known as coppicing,

> It is done at the beginning of each cropping season to reduce competition for water, minerals,
nutrients and sunlight with crops.

> The materials pruned or coppiced are used as fuel wood or for fodder crops.

 Grafting old trees:

> This is the practice of uniting two separate woody stems. > The part with the rooting system is
known as root stock (base) > The part which is grafted onto the rootstock is called a scion which
has buds that develop into the future plant. > The ability of the scion and the rootstock to form a

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successful union is known as compatibility. > Methods of grafting include whip or tongue
grafting, side grafting and approach grafting.

Agroforestry Practices

 Alley Cropping/Hedgerow Intercropping:

> The growing of multipurpose trees and shrubs together with crops.

Benefits

 Improve soil fertility through nitrogen fixation and organic matter.

 Provision of green manure.
 Used as fence and mark boundaries.
 Acts as windbreaks.
 Suppress weeds.
 Source of timber and fuel wood.
 Multi-storey cropping ;

> This is the growing together of trees of different heights.

> The system is based on crops which can tolerate shading.

> The trees and crops form different levels of canopy which look like storey.

Benefits

> Increases water consen/ation for pastures.

> None of the crops or trees included will be shaded.

> Act as windbreak for crops.

> Creates suitable micro-climate in the area.

> Trees are used for timber, fuel wood and forage.

 Woodlots (farm forests)

> These are plots of land set aside for trees only.

> They are established in the hilly and less productive parts of the farm.

> Fast growing tree species such as Eucalyptus spp. should be grown.

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Sites for Agroforestry:

 Farm boundaries - provide live fences.

 River banks - protect water catchment areas.
 Homesteads - provision of shade and windbreak
 Terraces - for soil conservation.
 Steep slopes - as contour hedges to encourage water seepage.

Tree Harvesting Methods

 Pollarding;

> This is the extensive cutting back of the crown of the tree about 2-3 meters above the ground
level to harvest all the side branches.

> It stimulates the development of a new crown and branches.

 Coppicing;

> Cutting the main stem of the tree completely at a height of 10 - 50 cm above the ground.

> The tree should be cut in a slanting angle.

 Lopping or side pruning;

> The removal of selected branches of the tree

> Done to produce fuel wood and fodder.

 Shaking of the tree;

> This is a method of harvesting pods and seeds from trees without cutting the tree.

 Cutting back;

> The tree is cut from the base to allow new growth as done in coffee when changing the cycle.

 Thinning;

> The removal of some of the trees growing in lines to give the remaining trees enough space to
grow.

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