THIRD TERM E-LEARNING NOTE

SUBJECT: AGRICULTURAL SCIENCE CLASS: SS 2

SCHEME OF WORK

WEEK TOPIC
1-2 Common Weeds Found in Farm: Meaning, Types, Examples and Economic
Importance
3-4 Crop Improvement: Meaning, Aims, Methods, Processes of Crop Improvement
5-6 Basic Economic Principles: Principles of Demand and Supply, Effects of Demand
and Supply, Law of Diminishing return
7-8 Farm Records and Farm Accounts
9-10 Animal Nutrition
11 Revision
12 Examination

REFERENCE BOOKS
 Essential Agricultural Science for Senior Secondary Schools, by O.A. Iwena
 WAEC PAQ
 Essential economics

WEEK ONE AND TWO

TOPIC: COMMON WEEDS FOUND IN FARMS
CONTENT
- Meaning of Weeds
- Effects of weeds on crops and the Economy
- Various types of weeds and their botanical names
- Methods of weed control

MEANING OF WEEDS
A weed is any plant that grows in a place where it is not (expected to grow) wanted

ECONOMIC IMPORTANCE OF WEEDS

1. They compete with crops for space
2. Weeds compete with crops for sunlight
3. Weeds compete with crop for nutrient
4. Weeds habour crop pests and pathogens
5. Weeds compete with crop for soil moisture
3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 1
 6. It leads to loss in crop yields
7. Weeds compete with crop for soil oxygen
8. They reduce the quality of crops
9. They reduce the income of farmers
10. They cause reduction in the taste of some grasses
11. Some weeds are toxic to farm animals

BENEFITS OF WEEDS TO FARMERS

1. Weeds helps in checking soil erosion
2. Some weeds are useful as food for humans
3. Some weeds serve as food for animals
4. Certain weeds have medicinal values
5. They can be used as green manure
6. Some are used for making roots, mats and baskets
7. Weeds are used for mulching
8. Weeds are used for compost making

EVALUATION
1. What are weeds?
2. List five beneficial effects of weeds

CHARACTERISTICS AND GROWTH HABIT OF WEEDS

1. Production of large quantity of seeds
2. Some weeds reduced by seeds
3. Some weeds reduced by vegetative propagation
4. Growth of large leaves within a short time
5. Weeds growth is favoured during rainy season
6. Most weeds are wind pollinated
7. Production of large quantity of pollen grains

DISPERSAL OF WEED SEEDS AND FRUITS

Most seeds and fruits of weeds are generally dispersed by wind and animals. The mode of
dispersal are;
1. Dispersal of seeds by wind
Such weeds have feathery, winged or powdery seeds e.g. Tridax (pwd weed), goats weed,
guinea grass, elephant grass and many other species of grasses.
2. Dispersal of seeds by Animal
Animal dispersed weeds usually have sticky, hooked, edible or colourful fruits or seeds.
The sticky and hooked types of fruits and seeds adhere to the coats of grazing animals
and are carried from one place to another. Examples of such animals are; rabbits, rats
squirrels, antelope and man. Pig weed and commelina spp are example of such weed.
3. Dispersal of seeds by water
Water dispered weeds have water proof cuticles, air spaces within the fruit and a light
weight
4. Dispersal of seeds by explosive mechanism
Few plants and all leguminouns weeds are dispersed by explosive mechanism eg water
leaf, centro, pueraria, calapo and mucuna.

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COMMON WEEDS FOUND ON FARMS
S/N COMMON NAME BOTANICAL NAME
1. Guinea grass Panicum maximum
2. Bahama grass Cynodon dactylon
3. Carpet grass Axonopus compressus
4. Cogon grass Imperata cylindrica
5. Spear grass Heteropogon contortus
6. Wild sun flower Aspilia Africana
7. Centro Centrosema pubescens
8. Water leaf Talinum triangulare
9. Wire/sida weed Sida acuta
10. Goat weed Ageratum conyzoides
11. Elephant grass Pennisetum purpureum
12. Giant star grass Cynodon plectostachyum
13. Pig weed Amaranthus spinosus
14. Tridax Tridax procumbens
15. Calapo Calapogonium mucunoides
16. Sunhemp Crotalaria juncea
17. Mucuna Mucuna utilis
18. Stylo Stylosanthes gracilis
19. Northern gamba Andropogon gayanus
20. Southern gamba Andropogon tectorum
21. Puero Pueraria phaseoloides

EVALUATION
1. List and explain different weed dispersal method
2. List five weeds and their botanical names

GENERAL CONTROL OF WEEDS

1. Mechanical control: involves the use of machines such as bulldozer, tree puller, plough
etc to get rid of unwanted plants.
2. Physical or manual control: This can be done in different ways which includes hand
pulling, hoeing, slashing with cutlass etc.
3. Biological Control: This involves the introduction of some insects and herbivorous
animals to farmland to eat up the leaves of the weed and even the entire plant in some
cases.
4. Cultural control: This involves the use of farming system to get rid of wed. It can be
achieved by practice of crop rotation and the growing of cover crops to suppress the
growth of the weeds on the farm. Other types of cultural weed control methods are:
flooding, bush burning, mulching
5. Chemical Control: This involves the use of chemical solution called herbicides to control
weeds. Some herbicides are selective while some are non-selective or contact herbicide

REASONS WHY WEEDS ARE DIFFICULT TO CONTROL

1. They have vigorous growth, they are aggressive and persistent
2. Weeds have high reproductive capacity
3. Their seeds have long period of viability
4. Weeds have efficient dispersal method
5. They have efficient means of propagation
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 6. They have long period of dormancy
7. They produce many seeds
8. They have short life cycle

GENERAL EVALUATION
1 a. What are weeds?
b. Discuss the methods of weed dispersal
2. List five economic importance of weeds
3. List five common weeds and state their botanical names
4. Discuss the four methods of weed control
5. Give three reasons why weeds are difficult to eradicate

READING ASSIGNMENT
 Essential Agricultural Science for senior Secondary School by O.A. Iwena Chapter 28
pages 249-260
 Answer the following questions from WAEC PAQ 2005 theory question 5

WEEKEND ASSIGNMENT
1. A cowpea growing in a maize plot is a ________ A. plant B. weed C. crop D. animal
2. Seed of centro, calapo are usually dispersed by _____ A. wind B. water C. explosive
mechanism D. animals
3. Which of the following is not a cultural weed control methods A. flooding B. burning
C. mulching D. hoeing
4. Which of the following is not a physical method of weed control? A. hand pulling
B. mulching C. hoeing D. slashing
5. Weeds have a _____ lifecycle A. long B. medium C. short D. average

THEORY
1. a. What are weeds
b. Describe four methods of weed control
2. a. List four benefits of weeds to farmers
b. State four reasons why weeds are difficult to control

WEEK THREE AND FOUR

TOPIC: CROP IMPROVEMENT
CONTENT
- Meaning of crop improvement
- Aims of crop improvement
- Methods of crop improvement
- Processes of crop improvement

MEANING OF CROP IMPROVEMENT

Crop improvement is defined as the science that deals with the development of new crop
varieties with superior quality and quantity.

AIMS OF CROP IMPROVEMENT

1. To increase yield
2. To improve the quality of produce
3. To adapt to climatic conditions
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 4. To increase resistance to diseases
5. To increase resistance to pests
6. To meet the needs of growers
7. To produce crops with uniform agronomic characteristics
8. To breed crops with early maturity
9. To improve nutrient value of the produce
10. To meet the needs of consumers

EVALUATION
1. What is crop improvement?
2. State five aims of crop improvement

DEFINITION OF SOME GENETIC TERMS

i. Genes: These are hereditary unit or basic unit of inheritance
ii. Chromosomes: They are rod or thread like bodies found in the nucleus of a cell
iii. Character or Trait: These are the inheritance attributes or features possessed by an
organism e.g. seed colour
iv. Gamete: It is a mature sex cell
v. Zygote: is a single cell formed as a result of the union of a male gamate with a female
gamate
vi. Allelomorphs (allele): These are pairs of genes on the position of a chromosome that
control a character
vii. Phenotype: is the sum total of all observable features of an organism i.e. physical,
physiological and behavioural traits e.g. height, weight and skin colour
viii. Genotype: is the sum total of the genes inherited from parent.
ix. Dominant character: This is a trait or character that is expressed in an offspring when two
individuals with contrasting character or traits are crossed
x. Recessive character: This is the character or trait which does not produce the effect in the
presence of dominant character.
xi. Homozygous: An individual is said to be homozygous if it has two similar genes for the
same character, i.e. the pair of gene controlling a given pair of contrasting characteristics
are identical e.g TT for height T for Tall or tt for height t for short
xii. Heterozygous: An individual is said to be heterozygous if the two members of a pair of
genes controlling a pair of contrasting characters are different. e.g Tt for height T for Tall
and t for short
xiii. Filial generation: The offspring of parents make up the filial generation. The first, second
and third filial generations are represented by F1, F2 and F3 respectively.
xiv. Hybrid: These are offsprings from a cross between parents that are genetically different
but of the same species.
xv. Hybridization: This is the crossing of plants with contrasting characters. There are two
major types of hybridization, this includes monohybridization and Dihybridization.
Dihybridization involves the crossing of plants with two pairs of contrasting characters.
Monohybridization involves the crossing of two pure traits.
xvi. Mutation: is a change in the genetic make-up of an organism resulting in a new
characteristic that is inheritable.

EVALUATION
1. Define; A. Gene B. Chromosome C. Trait
2. Explain; A. Mutation B. Hybridization C. Genotype

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MENDELIAN LAWS
1. The first law of Mendel is also called the law of segregation of genes states that; genes
are responsible for the development of the individual and that they are independently
transmitted from one generation to another without undergoing any alteration. This is
clearly seen in monohybrid crossing.
2. The second law of Mendel which is also called the law of independent assortment of
genes state that each character behaves as a separate unit and is inherited independently
of any other character. This is clearly seen in the dihybrid crossing.

PROCESS OF CROP IMPROVEMENT

These includes; introduction, selection and breeding of hybridization.
A. INTRODUCTION: This involves the importation or introduction of some varieties of crops
with desirable characteristics into areas where they have not existed before.

ADVANTAGES
1. It helps in bringing a new variety to a new areas
2. It may enhance greater productivity
3. It may perform better if there is a better climate condition
4. The past of the crop of the crops is usually absent in the new area

DISADVANTAGES
1. There is possibility of introducing a new diseases
2. The crop may not be able to adapt to climatic condition of the new environment
3. It may introduce now pests to the new environment
4. It may not be able to adapt to the soil condition of the area

B. SELECTION: This involves the picking of crops with desirable characteristics which are
most favored by the environment. Selection could be natural or artificial.

Natural selection involves the ability of a crop to survive wide range of environmental
conditions and still remain standing.

Artificial selection involves use of man’s intelligence to retain crops with desired traits on
the farm.

Methods of artificial selection includes;

1. Mass Selection: Crops with desirable characteristics are selected among others.
2. Pure line Selection: Only one crop plant with good characteristics is selected
3. Pedigree Selection: Crop plants are selected based on the performance of their ancestors
4. Progeny Selection: Crop plants are selected based on the performance of their offsprings

ADVANTAGES OF SELECTION
i. It ensures that only the best naturally available crop is grown
ii. Crops with desired qualities are selected
iii. Seeds from the best stands are multiplied for distribution
iv. It reduces the spread of diseases and pests

DISADVANTAGES OF SELECTION
i. Selection is tedious and time consuming
ii. It is very expensive in term of time and money
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 iii. It requires expertise
iv. It causes elimination of some desirable traits of the parent stick

C. BREEDING OR HYBRIDIZATION: is a method by which an offspring is produced

through the crossing of two different plant varieties of the same spices

TYPES OF BREEDING
i. Inbreeding: This is the pollination and fertilization of closely related crop plants. This
can lead to pure breed or pure line
ii. Pure line: It is obtained when a plant is being self-fertilized or crossed continuously with
a closely related species for many generations so that the desirable qualities it possess
does not change from one generation to another.
iii. Cross Breeding: This is the pollination and fertilization of unrelated crop plants
belonging to different breeds. This results in production of hybrids

ADVANTAGES OF BREEDING
i. It can produce a superior offspring resulting in hybrid vigor or heterosis
ii. Progeny grow more rapidly in cross breeding
iii. Offsprings can withstand the variation of environment

DISADVANTAGES OF BREEDING
i. Inbreeding leads to depressing or loss in vigor and performance of offspring.
ii. There is drop in production of the crops in quantity and quality in inbreeding
iii. It may leads to poor or low resistance to disease attacks in inbreeding

METHODS OF IMPROVING CROP PRODUCTIVITY

1. By crop improvement (Introduction, selection and breeding)
2. Planting at the proper time
3. Adoption of better cultivation methods
4. Use of manures and fertilizers
5. Control of pests of crops
6. Control of diseases of crops
7. Use of Resistant varieties
8. Use of good crop varieties

GENERAL EVALUATION
1. State the Mendelian laws
2. What is crop improvement
3. List three aims of crop improvement
4. State two advantages of breeding
5. State two methods of improving crop productivity

READING ASSIGNMENT
 Essential Agricultural Science for senior Secondary School by O.A. Iwena Chapter 39
pages 366-376
 Answer the following questions from WAEC PAQ 2005 theory question 6, 2008 theory
question 6, 2009 theory question 5 and 2011 theory question 6

WEEKEND ASSIGNMENT
1. The unit of inheritance is ______ A. chromosomes B. eggs C. genes D. gamates
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 2. __ are thread like bodies found in the nucleus of a cell A. chromosomes B. eggs C. genes
D. gamates
3. The fusion of male and female gamate result in ____ A. embryo B. genes C. gamates
D. zygote
4. An individual with pair of identical genes for the same character is called ____
individual. A. homozygous B. heterozygous C. gamates D. zygote
5. The character which express itself in the presence of the other is said to be ____
A. dominant B. recessive C. sexual D. asexual

THEORY
1. a. What is crop improvement?
b. State two aims of crop improvement
2. a. State the Mendelian laws
b. State two methods of improving crop productivity

WEEK FIVE AND SIX

TOPIC: BASIC ECONOMIC PRINCIPLES
CONTENT
- Basic economic concepts
- Principle of demand and supply
- Effects of demand and supply
- Law of diminishing return

BASIC ECONOMIC CONCEPTS

The following economic concept explains the behavior of consumers of agricultural goods.
These concepts or elements includes
1. Wants: this is the desire or needs of man to own goods and services that give satisfaction.
These wants are insatiable because the resources needed to cater for them are limited (in
short supply). The basic need or wants of man are food, clothing and shelter.
2. Scarcity: this refers to the limited supply of resources needed to meet (satisfy) wants.
3. Choice: this is the system employed in selecting one need to satisfy out of a number of
alternatives.
4. Scale of preference: is a list of unsatisfied wants in order of importance. This is relative
to the individual
5. Opportunity cost: is the satisfaction of one want or need at the expense of another. It is
expressed in terms of the value or worth of forgone alternative. It is also referred to as the
true or real cost while money cost is the amount spent in order to acquire a particular
good or service.

PRINCIPLES OF DEMAND AND SUPPLY

Demand: Demand may be defined as the quality of goods a consumer is willing and ready to buy
at a given price over a given period of time. Demand is effective when willingness to buy is
backed with the ability to pay.

LAW OF DEMAND
The law of demand states that the higher the price, the lower the quantity of goods that will be
demanded or the lower the price, the higher the quantity of goods that will be demanded.
DEMAND SCHEDULE

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This is a table showing the relationship between the price and quantity of that commodity
demanded. This table below obeys the law of demand.
Price N Quantity Demanded (kg)
100 10
80 20
60 30
40 40
20 50

DEMAND CURVE
Demand Curve is a graph showing the relationship between price and quantity of that commodity
demanded. This curve derived from demand schedule.
Demand Curve:
DEMAND CURVE
120
100
80
Price (₦)

60
40
20
0
10 20 30 40 50
Quantity demanded (Kg)

FACTORS AFFECTING DEMAND

1. Price of good
2. The price of other commodities
3. Income of the consumer
4. Changes in taste of consumer
5. Population
6. Periods of festivals
7. Expectation of changes in prices
8. Taxation

EVALUATION
1. What is demand?
2. List five factors affecting demand

SUPPLY
Supply may be defined as the quantity of goods which a producer is willing and ready to offer
for sale at a given price over a given period of time. Quantity of goods offered for sale in the
market is referred to as effective supply.

LAW OF SUPPLY
The law of supply states that the higher the price, the higher the quantity of produce that will be
supplied or the lower the price, the lower the quantity of produce that will be offered for sale.\

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SUPPLY SCHEDULE
Supply Schedule is the table which shows the relationship between price and quality of
commodity supplied. See the table below.
Price N Quantity Supplied (kg)
100 50
80 40
60 30
40 20
20 10

SUPPLY CURVE
Supply Curve is a graph showing the relationship between price and quantity of goods supplied
or offered for sale. The supply schedule is used to draw the supply curve as shown below.
Supply Curve:
SUPPLY CURVE
120
100
80
PRICE (₦)

60
40
20
0
1 2 3 4 5
QUANTITY SUPPLIED (Kg)

FACTORS AFFECTING SUPPLY

1. Price of good
2. Level of Technology
3. Cost of production
4. Government Policy
5. Weather condition
6. Taxation
7. Price of other commodities
8. Number of producers
9. Natural disasters

EVALUATION
1. What is supply?
2. State the law of supply.

LAW OF DIMINISHING RETURN

The law states that as successive amount of a variable factor are applied to one or more fixed
factors, output might increase a lot at first, but there comes a point at which the use of an
additional amount of the variable factor will add less to output than the proceeding amount.

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In other words, it state that as more and more units of a variable factor of a production are added
to fixed factor, after a certain point, the marginal product diminishes or declines.
Diminishing returns is caused by poor/inexperienced management resulting in the use of more
than required amount of one or more factors of production thereby making them less effective.

IMPORTANCE OF LAW OF DIMINISHING RETURNS IN AGRICULTURE

1. It enables managers effectively combine factors of production to attain optimal output.
2. It minimizes wastage on unproductive input.

DEFINITION OF TERMS
1. Fixed factors: these are assets or resources whose value does not change in the short run
e.g Land
2. Variable factor: these are assets or resources whose value changes in the short run e.g
capital, labour
3. Total product (TP or Q): is the overall quantity of output or yield produced by the farm.
4. Average product (AP): is the overall quantity of output or yield produced by the farm per
variable input.

5. Marginal product (MP): is the change in quantity produced resulting from change in
variable input.

This can be represented in the table below;

Fixed Variable Total output Marginal product Average product
factor factor (kg) (kg) (kg)
10 1 10 - 10
10 2 25 15 12.5
10 3 46 21 15.3
10 4 60 14 15
10 5 73 13 14.6
10 6 83 10 13.8
10 7 83 0 11.9
10 8 80 -3 10

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Graph demonstrating the law of diminishing return
Graph of TP/AP/MP
90
80
70
Increasing TP
60 +ve return
TP/MP/AP
o 50
decreasing
ut 40 Decreasing +ve return
p +ve return
30
20
AP
10
0
1 2 3 4 5 6 7 8
variable input MP

CLASS ACTIVITY (WAEC PQ)

1. State the law of diminishing returns.
2. Using the table below, make an input-output graph and describe the relationship between
fertilizer used and maize yield.
Quantity of fertilizer (bags) 0 4 8 12 16 20 24 28 32 36
Maize yield (Kg) 8 24 48 80 120 150 170 180 180 170
3. Explain the main cause of diminishing returns in agricultural production.

GENERAL EVALUATION
1. What is demand?
2. State the law of demand
3. What is supply?
4. State the law of supply
5. State the law of diminishing return
6. Differentiate between total product, marginal product and average product.

READING ASSIGNMENT
 Essential Agricultural Science for senior Secondary School by O.A. Iwena Chapter 35
pages 343 – 347 and Chapter 37 pages 353 – 362,.
 Answer the following questions from WAEC PAQ 2007 theory question 9, 2008 theory
question 9 & 10, 2012 theory question 9 & 10, 2014 theory question 5, 2017 theory
question 6, 2000 theory question 9, 1994 theory question 9 and 1991 theory question 9

WEEKEND ASSIGNMENT
1. The higher the price, the ____ the quantity demanded A. higher B. lower C. up D. down
2. Increase in population will lead to _____ demand A. high B. low C. medium D. long
3. The real cost of an item is the ____ A. cost of forgone alternative B. amount spent to
acquire the item C. cost of substitute item D. money cost of the item
4. Short run in production refers to ____ A. a period in which there is at least one fixed
factor of production B. a period in which there is at least one variable factor of
production C. a period in which there is no fixed factor of production D. a period in
which there is variable factor of production
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 5. An example of variable input in poultry production is? A. Land B. Feed C. Fertilizer or
manure D. Incubator

THEORY
Complete this table
Quantity of fertilizer (bags) 0 4 8 12 16 20 24 28 32 36
Maize yield (Kg) 8 24 48 80 120 150 170 180 180 170
Marginal product (Kg)
Average product (Kg)

WEEK SEVEN AND EIGHT

TOPIC: FARM RECORD AND FARM ACCOUNT
CONTENT
- Meaning of Farm Accounts/Farm records
- Importance of Farm Account / farm records
- Types of Farm Record
- Types of Farm Account

MEANING OF FARM ACCOUNTS AND RECORDS

FARM ACCOUNT
Farm Accounts are statements of money paid out or received for goods and services used in a
farming business.

FARM RECORD
Farm Records are written documents, showing major activities going on in the farming business

IMPORTANCE OF FARM ACCOUNTS/RECORDS

1. It enables the farmer to monitor the changes in prices of product brought or sold.
2. It shows the financial position of the farm
3. It helps to determine profit
4. Detection fraudulent decisions
5. For taking informed management decision
6. For procurement of loans
7. For determination of annual tax
8. Determining the actual worth of the farm
9. For comparing management efficiency
10. To evaluate performance of an enterprise
11. To estimate future farm returns.
12. It provides basis for conducting research.
13. To monitor health status of crops and animals.

EVALUATION
1. What is farm record and account?
2. List five importance of keeping farm records and account.

TYPES OF FARM RECORD

1. Farm Diary: This is the record of daily activities
2. Farm Inventory: This is the list of all assets on the farm and their money worth or value
3. Sales and purchase record: record of revenue and expenses made by the farm business.
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 4. Yield or production record: it contain the information on output of crops and animal
product
5. Payroll or labour record: It shows the amount and types of labour hired or employed to
work on the farm and rate at which their wages are paid
6. Farm Input Utilization Record: It shows the input required, utilized and their level of
input application.

TYPES OF FARM ACCOUNT

1. Sales Account: Sales Account is also known as sales and receipt account. This shows
data of farm produce, the quantity, date sold, to whom and at what price.
2. Purchase Account: It is also known as purchased for use on the farm.
3. Farm Valuation: This is the value of the farm at the beginning and end of production. At
the beginning it is called opening valuation while at the end, it is called closing valuation.
4. Cash Analysis Account: It shows the details of the income and expenditure of a farm over
a given period of time
5. Farm Income Statement: It comprises of all the farm receipts (sales) and expenses came
out on the farm over a period of time as shown below;

INCOME STATEMENT OF AKANDE FARMS FOR OCTOBER, 1995

EXPENSES ₦ RECEIPT ₦
Feeds 2000 Egg 5000
Drugs 400 Culled layer 3000
Water 100 Manure 200
Labour 500
Fuel 200
Net Income 5000
Total 8,200 8,200

6. Balance Sheet or Networth Statement: The balance sheet shows the capital or financial
position of the farm at the end of the accounting period usually a year.
7. Profit and Loss account: This is the type of account prepared at the end of the business
period, usually a year. By farmer with the purpose of knowing weather his business is
making profit or loss.
In this account, all expenses and purchases are listed on the left hand side i.e. debit side
and all receipts on sales are recorded on the right hand i.e. credit side. Closing valuation
is also put on the right while opening valuation is put on the left.

IMPORTANCE OF PROFIT AND LOSS ACCOUNT

1. It helps to detect if the farm is making profit or a loss
2. It helps to determine the overall performance of the farm at the end of the account period
3. It aids future planning of the farm for better results.

Example
Prepare a profit and loss account for Segun Farms for the year which ended 31/12/17, using the
following data;
i. Cost of feed N500
ii. Cost of drugs N 200
iii. Sales of Eggs N 2000
iv. Eggs for domestic use N 200

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 v. Loss due to mortality N 300
vi. Value of stick left N 600
vii. Farm wages N 400
viii. Sales of spent layers N 1000
ix. Transportation cost N 300
x. Depreciation N 200
xi. Electricity bill N 300
xii. Net profit N 1600

SOLUTION
SEGUN FARMS PROFIT AND LOSS ACCOUNT AS AT 31ST DECEMBER, 2017
DEBIT CREDIT
S/N ITEMS ₦ S/N ITEMS ₦
1 Cost of feed 500 1 Sales of spent layers 2000
2 Cost of drugs 200 2 Eggs for domestic 200
use
3 Loss due to mortality 300 3 Value of stick left 600
4 Farm wages 400 4 Sales of spent layers 1000
5 Transportation cost 300
6 Depreciation 200
7 Electricity bill 300
8 Net profit 1600
Grand Total 3800 Grand Total 3800

EVALUATION
1. a. List five types of farm record
b. Explain any two of record mentioned
2. a. List five types of farm account
b. Explain profit and loss account

DEFINITION OF SOME ACCOUNTING TERMS

1. Farm Asset: This is anything of value in the possession of a farm business, There are two
types;
a. Fixed Assets: These are assets which are not used up during production. Examples
are; landed property, farm building, motor vehicles, tools and implements, incubator
and milking machine
b. Current Assets: These are assets which are used up during the process of production
eg water, feed, drugs, chemical, fertilizers, seeds and cash in bank.
2. Cost: these are expenses made during production. There are two types fixed and variable
cost
a. Fixed Cost: This is the component of the total of production cost which does not vary
with the level of production e.g. cost of buildings, equipment, machineries, farm
structures (Silo, barn e.t.c)
b. Variable Cost: This is the other component of the total cost which varies directly with
the level of production e.g wages, salaries, cost of seeds, cost of fertilizer, cost of
agrochemical e.t.c
3. Liabilities: This is the money owed to external persons or corporate bodies e.g. loan to
banks. The two types are;

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 a. Current or short term liabilities: These are debts that must be paid back within one
accounting year
b. Long term liabilities: These are debts that cannot be paid within an accounting year
4. Net Capital, Net worth or owner equity: This is the total amount of money supplied by
the owner of the farm business.
Asset – Liability = Owner’s Equity or Capital
5. Liquidity: is the ability of a farm business to meet its financial obligations as they fall
due. It is the ease at which farm asset can be covered to cash.
6. Solvency: This is the ability of the farm business to cover its liquidation of the asset. A
business is solvent if the sale of its assets would be sufficient to pay off all debts
7. Appreciation: This is the increase in the value or worth of an asset as the asset is being
used over time. Examples of assets that can appreciate are; growing animals, cash crops,
land etc.
8. Depreciation: Depreciation refers to the loss or reduction in the value or worth of an asset
as the asset is being used over time
9. Salvage Value: This is the amount at which an asset is sold off when it is no longer
economical to keep, or when the cost of maintenance is too high
10. Useful life Span: This means the number of years a piece of farm equipment can
effectively serve the farmer.

EVALUATION
1. Define the following: (i) Appreciation (ii) Solvency (iii) Liquidity
2. Distinguish between fixed assets and variable assets.

Calculations of Depreciation and Salvage Value

The formula for calculating depreciation is as follows,
a. Total depreciation = cost price of asset – salvage value of asset

b. Annual depreciation =
Example: A plough was purchased in 1985 at the cost of N 6000 and sold off in 1990 at the cost
of N 1000
Calculate;
i. The salvage value
ii. Total depreciation
iii. Annual depreciation
iv. Appreciation

Solution
- Cost price of the plough = N 6000
- Salvage value = N 1000
- Lifespan of useful life (1990 - 1985) = 5years
i. Salvage value = N 1000 i.e the price at which it was sold off
ii. Total Depreciation
= Cost price – salvage value
= N 6000 – N 1000
= N5000
iii. Annual Depreciation

3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 16

 =

=
=N1000 (annual depreciation)
iv. There is no appreciation

CLASS ACTIVITY
Answer questions 3, 4, 6 and 9 from Essential Agricultural science on Page 448.

GENERAL EVALUATION
1. What are farm records and account?
2. List five importance of keeping farm records and accounts.
3. List five types of farm account.
4. Distinguish between fixed and variable cost.

READING ASSIGNMENT
 Essential Agricultural Science for senior Secondary School by O.A. Iwena Chapter 48
pages 440-449
 Answer the following questions from WAEC PAQ 1989 theory question 10, 1993 theory
question 10, 1996 theory question 10, 1997 theory question 10, 1998 theory question 10,
2013 theory question 9 & 10, 2009 theory question 9 & 10, 1999 theory question 9, 2006
theory question 9 and 2007 theory question 9

WEEKEND ASSIGNMENT
1. In profit and loss account, opening valuation is put on the _____ A. credit side B. debit
side C. and side D. all sides
2. Ability of farm to meet its financial commitment as the falls due is _____ A. solvency B.
liquidity C. depreciation D. appreciation
3. The amount at which an asset is sold off when the cost maintaining it is high is called
____ A. useful life B. lifespan C. salvage value D. asset
4. Day to day activities on the farm are recorded in _____ A. register B. diary C. payroll D.
inventory
5. Farm assets are recorded in _____ A. diary B. register C. inventory D. labour

THEORY
1. a. What is profit and lost account
b. List five types of farm records
2. a. What is farm asset
b. Distinguish between credit and subsidy

3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 17

WEEK NINE AND TEN
TOPIC: ANIMAL NUTRITION
CONTENT
- Meaning of Animal Nutrition
- Classification of livestock feeds
- Food Nutrients of livestock

MEANING OF ANIMAL NUTRITION

Animal nutrition is the process by which an animal obtains nutrient necessary for its healthy
growth and development.

IMPORTANCE OF ANIMAL FEEDS

1. Animal feeds are needed for growth
2. Useful for repair or worn out tissue
3. It provides energy
4. It is useful for the general well-being of the animal.
5. It aids animal’s resistance to diseases.
6. It influences maturity in animals.
7. It aids optimal production in animals.

DEFINITION OF FEED
Feed refers to the food given to animals. They contain nutrient element either alone or in
combination with other substances which supports the healthy growth and development of
livestock.

CLASIFICATION OF LIVESTOCK FEEDS

Animal feeds can be classified into four main groups according to the digestibility, quantity of
fibre, quantity required and moisture in the feed. The four groups of feeds are;
1. Concentrates: They are fee with a low proportion of fibre and water content. They are easily
digested by farm animals. Concentrates can be further be subdivided into two groups: Those
containing a high proportion of carbohydrates are called carbohydrate concentrates/basal
feed/energy feed e.g maize, guinea corn, cassava e.t.c while those with a high proportion of
proteins are called protein concentrates e.g beans, peas, cotton seed, sunflower seeds and
heads, groundnuts, palm kernel and animal products such as meat, blood meal, bone meal,
fishmeal and milk.
2. Roughages: Roughages are very low in protein and carbohydrate but high in fibre. They are
not easily digested by animals, therefore are fed together with concentrate foods for young
animals and those kept for milk and meat production. Examples are hay, groundnut hulls,
straw, bean pods and maize stover.
3. Succulents: These have high water content. They are easy to digest. Examples are freshly
cut/lush grass and legume plants (soilage), pumpkin, silage, melons and most green crops.
4. Supplements (minerals and vitamins): they are required in small quantities, low in energy,
protein and fibre but high in vitamins and minerals. They aid digestion and increase animals
resistance to diseases. They are available in basal and protein concentrate feeds. Other
sources are bone meal, oyster shell, salt licks etc.

A. Basal/Energy Feed or Carbonhydrate Concentrates

Characteristics
i. They are fed with crude fibre content less than 18%
ii. They are high in energy and starchy food e.g. maize and cassava
3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 18
 iii. It is high in carbohydrates or fats
iv. It is low in proteins
v. Low in fibre
vi. It is highly digestible
vii. It is low in minerals

B. Protein Concentrate
Characteristics
i. They crude fibre content is less than18%
ii. Protein concentrate is high in protein
iii. They are low in carbohydrates and fats
iv. They are low in fibre
v. They are highly digestible
vi. They are low in minerals

C. Mineral and Vitamin Supplements

Characteristics
i. They are required in small quantities in feeds
ii. They supplement basal and protein concentrates
iii. They are low in energy
iv. Low in protein
v. Low in fibre
vi. High is vitamin and minerals
vii. Necessary for growth and development
viii. They aid food digestion
ix. They aid resistance to diseases

D. Roughages
Characteristics
i. They are feeds which contain crude fibre that is greater than 18%
ii. They are high in fibre
iii. They are low in digestible carbohydrates
iv. They are low in protein
v. They have poor or low digestibility
vi. Pasture grasses and legumes form roughages
vii. Roughages exist in different forms which are; hay, straw, soilage and salvage.
Hay: It refer to the aerial part of a young and succulent grass or herbage cut and dried for
feeding animals

Straw: This is the aerial part of grass or harvested crops cut and store for future use. They are
difficult to digest. Both hay and straw are called dry roughages

Soilage: This refer to the process of cutting fresh or succulent grass or legumes from the field
and taking them to the animals in their pens. It is also called zero grazing

Silage: This refers to the preservation of green and succulent forage crops under anaerobic
conition.

ACTIVITY
Describe the preparation of silage.
3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 19
EVALUATION
1. What is animal nutrition?
2. State the classes of animal feed

ANIMAL FEED INGREDIENTS

These are the raw materials used in production of animal feeds. These includes; blood meal, fish
meal, groundnut cake, palm kernel cake, cotton seed meal, bone meal, maize, guinea corn etc.

ACTIVITY
Explain the method of preparing the ingredients mentioned above.

FOOD NUTRIENTS OF LIVESTOCK

There are six classes of food nutrients. These are;
1. CARBOHYDRATE: It is made up of carbon, hydrogen and oxygen.
Sources: Maize, guinea corn, cassava, grasses, wheat, potato, rice, millet, yam, hay, silage,
potato, rice millet, yam, hay, silage potatoes etc
FUNCTIONS OF CARBOHYDRATES
Provides energy to farm animal for growth, reproduction, milk production and other activities.

2. PROTEIN: It is composed of carbon, hydrogen, oxygen and sometimes sulphur, nitrogen

and phosphorus
Sources: The sources of animal proteins are; fish meal, blood meal, meat meal, milk,
earthworms, eggs e.t.c. Plant proteins sources are; soyabeans meal, groundnut cake, palm kernel
cake, cotton seed meal, sunflower seed meal, cashewnut meal and leguminous forage. Synthetic
sources of proterins are; methionine, lysine, cysteine
FUNCTIONS OF PROTEIN
i. Essential for the growth of young animal tissue
ii. They are used to repair worn out tissue
iii. They are used in the formation of gamates in reproduction
iv. They are needed for the production of enzymes
v. They are necessary for flesh built-up
vi. Essential for sustenance of life
vii. Help to provide raw materials for building protective covering such as hair, nails roof, wool
feather e.t.c.
viii. They are useful in the production of

3. FATS AND OIL

Fat are composed of carbon, hydrogen, and oxygen
Sources: These are palm oil, palm kernel cake, groundnut cake, coconut meal, cotton seed cake,
milk, lard and fallow.
FUNCTIONS OF FATS AND OIL
i. Fats provide more energy than carbohydrates
ii. Fat supply essential fatty acids and fat build-up
iii. They provide fat soluble vitamins
iv. They improve the diet
v. They help in the maintenance of body temperature

4. MINERALS: these are essential elements needed by the body but which the body cannot
produce. They are grouped into two major classes:
1. Structural mineral elements: Carbon, Hydrogen, Oxygen and Nitrogen
3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 20
 2. Mineral elements is further divided into
a. Macro-elements or mineral: These are required by animals in large quantity e.g.
calcium, photophorus, magnesium, potassium, sulphur, sodium and chlorine
b. Trace Elements or micro elements: These are required by animals in small quantity
e.g. iodine, cobalt, copper, manganese, zinc and fluorine.
Sources are born meal, oyster shell, limestone and salt licks
FUNCTIONS OF MINERAL
a. It helps to ensure good health and productivity
b. Present in muscles for muscle contractions
c. Constituent of milk, egg and meat
d. Help in the formation of hormones.
e. Maintain PH balance of body fluids
f. They prevent diseases
g. Regulate blood clothing
h. Help in bone and teeth formation
i. Prevent tooth decay

MINERALS SOURCES FUNCTIONS DEFICIENCY SYMPTOMS

Calcium Bone meal, oyster shell, Bone and teeth formation Ricket, osteomalacia, soft egg
limestone, milk rock Egg shell formation shell.
calcium phosphate Blood clotting Retarded growth
Phosphorus Bone meal, Dicalcium Bone and teeth Ricket, Lack of appetite.
phosphate, fish meal formation; Acid-base Osteomalcia
balance; Egg shell
formation
Magnesium Salt licks, wheat germs, Aid functioning of the Hyper-irritability, Nervous
forage, grasses nervous system. disorder Called tetany
Activation of enzymes
Sodium and Common salt, salt licks, Regulates acid-base Reduced growth and weight;
Chlorine fish meal balance; Maintenance of decline in appetite.
osmotic pressure,
constituents of Hcl
Improves pleasant taste
of feed.
Sulphur Salt licks, fish meal Constituent of protein Poor growth
and amino acids like
cysteine, methione
Iron Yeast, iron injection, salt Constituent of Anaemia e.g. baby pig
licks haemoglobin in red blood anaemia of piglets.
cell. Constituent of
protein called
myoglobuline
Iodine Iodined salts, fish meal Constituent of hormone Goitre
called thyroxine
Cobalt Salt licks, Activate some Constituents of vitamins General malnutrition
enzymes B12
Copper Salt licks Aids formation of Anaemia
haemoglobin & Iron
absorption

3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 21

Flourine Salt licks, fluorinated Prevents tooth decay Tooth decay.
water

5. VITAMINS: are organic substances also required by animals for proper growth and bosy
development. The types are;
a. Fat Soluble Vitamins: These are vitamins which are soluble in fat e.g. A,D,E and K
b. Water Soluble Vitamins C and B-Complex. Examples of vitamin B-Complex are;
cobalamine, pantothenic acid and folic acid.

MINERALS SOURCES FUNCTIONS DEFICIENCY SYMPTOMS

Vitamin A Fish meal, grasses, Proper eye sight (or vision), Nightblindness
(retinol) yellow maize Epithelical cell formation,
Aid reproduction.
Vitamin C Grasses, vegetables Formation of connective Scurvy
(Ascorbic) acid and fruits. tissues, bone and dentine
Vitamin D Bone meal, fish Aids bone and teeth Ricket, Osteomalacia, soft shell
(Calciferol) meal and sunlight formation, egg shell egg.
formation
Vitamin E Vegetables, grasses, Aids reproduction. Reproductive failure like
(Tocopherol) synthetic vitamin E As an antioxidant. sterility and premature
Vitamin K Fish meal, Aids blood clotting. Haemorrhages i.e inability of
(phylloquinone) vegetables Prothrombin the blood to clot in time.
Vitamin B1 Yeast, cereals, Co-enzyme in energy Poor appetite, Bere-beri
(Thiamine) green plants metabolism
Vitamin B2 Green herbage and Co-enzyme in protein and Slow growth, Dermatitis
(Riboflavin) milk products fat metabolism
Vitamin B12 Fish meal, milk As co-enzyme in several Pernicious anaemia.
(Cobalamin) products biochemical reactions.
Red blood cell formation
Vitamin B3 Yeast, cereals, Carbohydrate oxidation Pellagra
Niacin grasses
(Nicotinic acid)

6. WATER
Sources of water; tap, feed, rain, rivers, pond and fresh fodder.
FUNCTION OF WATER
1. Water is provided for drinking purposes
2. It is used for metabolic and digestion of food
3. For dipping/drenching animal against ectoparasites
4. For washing or cleaning of animals
5. For sanitation, cleaning of floor and pens
6. For processing animal products
7. For maintenance of body temperature
8. For irrigation of pasture
9. It helps to get rid of waste products in the body
10. Helps to maintain body turgidity

FUNCTIONS OF ANTIBIOTICS
1. Helps to fight against pathogen

3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 22

 2. Helps to heal sore and wounds in animals
3. They increase absorption of nutrient from digestive tract

EVALUATION
1. State five functions of proteins.
2. What are macronutrient?

TYPES OF RATION/DIET AND THEIR USES

Diet: is defined as the feed formulated to meet specific needs of an animal. It is also referred to
as the amount of feed regularly given to or consumed by animal. It is formulated to meet specific
metabolic or physiological functions such as growth, location, maintenance of pregnancy,
reproduction or egg laying.

Ration: is the total supply of food given to animals in a twenty four hour period.
Balanced Ration: A balanced ration is the feed containing all essential nutrients in the correct
quantity and in adequate proportion for feeding animals.
Types of balanced ration
1. Maintenance Ration: This is given to farm animals just to maintain normal functioning
of the body system.
2. Production Ration: This is the type of ration given to farm animals to enable them to
produce.

Factor to be considered when deciding the type of Ration to feed an Animal

1. The purpose for which the animal is kept
2. Age of the animal
3. Animal’s condition of health
4. Management System
5. Physiological state of the animal

Categories of farm animals that require production ration are;

a. Lactating animals
b. Weaned animals
c. Pregnant animals
d. Fattening animals
e. Broiler
f. Layers
g. Steaming up or flushing

GENERAL EVALUATION
1. What is balanced ration?
2. Distinguished between production and maintenance ration
3. State five functions of vitamins
4. State five functions of water

READING ASSIGNMENT
 Essential Agricultural Science for senior Secondary School by O.A. Iwena Chapter 33,
pages 329-338
 Answer the following questions from WAEC PAQ 1995 theory question 7, 2012 theory
question 8 and 2014 theory question 4

3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 23

WEEKEND ASSIGNMENT
1. ____ is essential for bone formation A. iron B. calcium C. carbon D. lodine
2. Night blindness is as a result of lack of vitamin ____ A. A B. B C. C D. D
3. Ricket is as a result of deficiency of vitamin ____ A. A B. B C. C D. D
4. Which of these is a micronutrient A. calcium B. manganese C. magnesium D. sulphur
5. Goitre is as a result of deficiency of ____ A. iron B. cobalt C. copper D. lodine

THEORY
1. a. What is a nutrient?
b. List five characteristics of roughages.
2. a. Define (i) Diet (i) nutrition (iii) production ration
b. State five functions of proteins.

3RD TERM/AGRICULTURAL SCIENCE/SS 2 Page 24