INTESTINAL MORPHOLOGY AND LIVER HISTOLOGY OF MALLARD

DUCK SUPPLEMENTED WITH MADRE DE AGUA

(Trichantera gigantea) LEAF MEAL

RALPH DENMARK A. CALAMASA

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THESIS OUTLINE
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Republic of the Philippines

ISABELA STATE UNIVERSITY

Echague, Isabela

January 2023
 I. INTRODUCTION

A. Importance of the Study

Poultry is a high-quality animal protein source, and various strategies have been used to

boost poultry production profitability. Determination of nutrient requirements of different types

of poultry is necessary to efficiently use the genetic potential of these birds for specific

production goals (Pym, 1990). Dietary nutrient density is the most critical nutritional factor in

commercial production, not only because it has a significant effect on growth performance,

carcass quality, and health of poultry, but also because of economic inputs and outputs (Scott,

2002; Sterling et al., 2005; Brickett et al., 2007).

Duck raising is a lucrative livestock industry in the Philippines because of its egg. Ducks

are the next to chicken in terms of economic importance of source of eggs as well as meat. Local

farmers and entrepreneurs ventured into duck farming because of some economic value and

significant role in the Filipino culture. Duck farming does not require costly and elaborate

housing facilities which needed slight space for rearing purposes. It can succeed in a wide range

of climatic and nutritional conditions (Dagaas and Chang, 2004), resilient to avian diseases, and

can subsist on a various feedstuff.

The Philippine native mallard ducks (Anas platyrynchos Lin.) are raised by smallholders

that provides low-cost animal protein and incomes for the poorer sector of the population in the

rural areas through selling of duck eggs either fresh or boiled which duck eggs has demand

higher prices than the table eggs of chicken Ampode and Espina, (2019) reported that duck egg

sizes are large, thick shells, and suitable for processing into value-added products such as salted,

boiled and balut (embryonated egg).

 Perception of consumers on raw and cooked meat quality have created significant interest

in increasing the understanding of digestive physiology and the dynamics of the gut microflora

(Dibner and Richards, 2005). Physiological studies reveal that a functional gastrointestinal track

is vital for the digestion and absorption pf nutrients required for the bird’s maintenance and

growth (Mateos et al., 2002., Baurhoo et al., 2009).

The digestive track is the main site for digestion and absorption of nutrients in animals. It

also acts as the largest immunological organ in the body, as it is the first point of protection

against exogenous pathogens that enter the body, preventing the pathogens from colonization

and entering the host cells and tissues (Choct, 2009). A balanced gut microorganism population,

consisting of less pathogenic bacteria, and an increase in beneficial bacteria, may result in an

increase in availability of nutrients (Hashemi and Davoodi, 2010).

The liver is regarded as an essential and biggest gland of the body, and it plays a crucial

role in numerous physiological processes such as synthesis of blood proteins, production and

secretion of bile, detoxification, nutrients absorption, metabolism of several substances and

storing metabolites (Saez et al., 2012., Odokuma and Omokara, 2015).

A number of additives from plants have been reported to contain nutrient properties that

affect gut microflora, intestinal morphology and meat quality of poultry. One of the possible

sources of cheap protein is the leaf meal of some tropical legumes and browse plants to boost

their income though poultry business (WAC, 2006). Leaf meal supplements have been also

included into the diets of poultry birds as means of increasing weight, improved gut health and

thereby reducing cost of production (Nworgu and Fapohunda, 2002; Esonu, et al., 2003;

Nworgu, et al., 2012).

 Traditionally, supplementation of protein to ducks during egg production is practiced.

Unfortunately, sources of supplement such us snails and small shrimps have become scarce. In

this regard, there is a next to explore to potential locally available plants as protein source to

lessen feed cost increase the profit of duck raisers (Lacayanga, 2015). Trichantera (trichantera

gigantea), also known as Nacedero, can be considered for this purpose. It is fodder tree that adapt

well in tropical conditions, grows easily between plantation crops, its protein content ranges

from 17% to 22% on DM basis and high calcium content compared to other fodder tree (Rosales,

1997; Garcia et al., 2008).

B. Objectives of the Study

Generally, the study will be conducted to evaluate the intestinal and hepatic morphology

of mallard duck supplemented with madre de agua (Trichantera gigantea) leaf meal.

Specifically, this study will be aims to:

1. Determine the level of trichantera leaf meal that could affect or influence the intestinal

surface area (villus height and crypt depth of the jejunum) and histological feature of

liver of the improved Philippine mallard duck, and

2. Evaluate the effect of trichantera leaf meal on improved Philippine mallard duck in terms

of body weight, gain in weight, feed consumption, feed conversion ratio, and efficiency.

C. Time and Place of the Study

This study will be conducted at the Itik Pinas Production Area, Cagayan Valley

Agriculture Resources Research and Development, Isabela State University, Echague, Isabela

from January to April 2023.

D. Scope and Delimitation of the Study

The study will focus on the intestinal morphology and liver histology of mallard duck

supplemented with madre de agua (Trichantera gigantea) leaf meal on the jejunum villi height,

jejunum villi width, jejunum villi width, jejunum villi width, histological feature of liver, body

weight, gain in weight, feed consumption, and feed conversion ratio (FCR).

E. Definition of Terms

The following are words used in the study for better understanding:

Ad-libitum. It refers to the availability of feeds where animals/birds are full fed or

allowed to eat as much as they can from start to market.

Broiler. It refers to the relative homogenous group of chicken in which specie develops

and maintain by human.

Brooding. It is the process of subjecting young animals to heat and warmth in order to

increase their chances of survival.

Complete Randomized Design. It refers to the experimental design, which is appropriate

for experiment with homogenous experimental unit, in a controlled environment

Diet. The sum of feed consumed by an animal.

Dress Weight. It refers to the weight of dressed bird without its feather, head, and visceral

organs.

Dressing Percentage. It refers to the percent yield of carcass, determined as the weight of

dress chicken divided by its live weight then multiplied to 100.

 Feed Conversion Efficiency. It refers to the ability of bird to convert the number of

kilograms of feed to a corresponding weight of meat.

Feed Conversion Ratio. It refers to the amount of feed required to produce gain in weight

of birds.

Feeding. Is the act, process, or manner of giving the right kind, amount and quality of

feeds at the right age of animals.

Feeds. It is any material which after ingestion of animals is capable of being digested,

absorbed, and utilized.

Feed Formulation. It refers to the process by which different feed ingredients that are

proportionally combined to give the animals appropriate nutrients needed by them.

Gain in Weight. It refers to the difference between initial weights to current weight.

Growth. It refers to the increase in size and weight of chicken in a definite interval of

times.

Hygiene. It refers to the promotional and maintenance of the health and cleanliness of the

animals.

Leaf Meal. The term refers to fresh plant leaves properly dried and ground; usually used

as supplement in feeding livestock and poultry.

Mortality. It refers to the number of birds that died in the herd within the rotation of the

study.

Performance. It refers to the reaction of the broiler to its environment

 Pigmentation. It refers to the coloration of the skin, beak, and shank of the bird.

Poultry. It refers to the collective term for domesticated birds for man’s consumption.

Replication. It refers to the repetition of the experimental treatment to compare the result

of each other.

Supplementation. Provide nutrients either extracted from feed sources or that are

synthetic in order to increase the quantity of their feed consumption.

Trichantera (Trichantera gigantea). Also known as Nacedero, can be considered for this

purpose. It is a fodder tree that adapts well in tropical conditions, grows easily between

plantation crops. Its protein content ranges from 17% to 22% on DM basis and has high calcium

content compared to other fodder trees.

 II. REVIEW OF RELATED LITERATURE

A. Morphology of Madre de Agua (Trichantera gigantea)

Trichanthera gigantea is a small to medium sized shrub, generally about 5 m high but it

can grow to a height of 12-15 m (Cook et al., 2005; Rosales, 1997). The crown is 6 m in

diameter and the tree is many branched. Branches are quadrangular with rounded nodes and

minutely haired tips. The leaves are oppositely borne on 1-5 cm long petioles. Leaf blades are 26

cm long x 14 cm broad, ovate to oblong in shape, dark green on the upper surface and paler on

the underside. The inflorescences are compact terminal panicles bearing 10-20 bell-like flowers.

The corolla is 3-4 cm long, red at the base and becoming yellow at the throat. Nacedero flowers

have conspicuous, long, hairy anthers (the latin name Trichanthera means "hairy anther"). Fruits

are dehiscent woody capsules, containing between 4 and 40 seeds, which split open once the

seeds are mature (Cook et al., 2005; Rosales, 1997). Like all plants of the Acanthaceae family,

Trichanthera gigantea forms cystoliths, which are small mineral concretions that appear as

minute short lines on the upper surface of the leaves, the upper portions of the stems, on the

branches of the inflorescences and on the calyx (Rosales, 1997).

Nacedero is a very versatile species. It can be cultivated from sea level up to 2000 m. It

grows on a wide range of soils, including those that are acidic and infertile with a pH as low as

4.5. Trichanthera gigantea does better where average temperatures are high (around 30°C) and

where annual rainfall is in the range of 1500 mm to 3000 mm. It can grow in places where

rainfall is lower (1000 mm), but then it drops its leaves during dry periods. It tolerates much

higher rainfall (5000-8000 mm) provided that the soil is well-drained (Ecocrop, 2014). Nacedero

is sensitive to frost which is one of its most important limitations. It is more productive under
shade than in full-light and does better for instance under leucaena or banana shade (Cook et al.,

2005; Rosales, 1997).

B. Nutritional Attributes

Nacedero foliage is relatively rich in protein (13 to 22% DM), though lower values have

been recorded (Rosales et al., 1999; Rosales, 1997; Nguyen Xuan Ba et al., 2003). Most of the

crude protein is true protein and the balance of amino acid appears to be good (Rosales et al.,

1999; Rosales, 1997). The ash content (often more than 20% DM) and more specifically the

calcium content has been found to be particularly high compared with other fodder trees (Garcia

et al., 2008; Rosales, 1997). This can be explained by the presence of cystoliths in the leaves,

which may help to explain why, on farms in Colombia, nacedero is used as a lactogenic drink,

which may have potential for feeding lactating animals (Rosales, 1997). The fibre content is

extremely variable, with reported NDF values ranging from 33 to 66% of the DM.

Nacedero foliage is free from alkaloids and condensed tannins, with low contents in

saponins and steroids. Phenol content was extremely variable, from 0.045 to 5% of DM, which

has been suggested to be the cause of the large variations of nutritional value observed in feeding

trials with Trichanthera gigantea. The tannins from nacedero may be of the hydrolysable type

(Rosales, 1997). In Venezuela, in a comparison of 11 other forage tree species, nacedero had no

detectable concentrations of coumarins, saponins, or bitter compounds, low concentrations of

alkaloids and moderate contentrations of terpenes (Garcia et al., 2008).

The high protein content of nacedero leaves could be valuable for poultry feeding, despite

a high fibre content that limits their energy value (Rosales, 1997). They can be an element of

extensive poultry production systems based on alternative feed ingredients (Ruiz-Silvera et al.,
2008). Some trials investigated the potential of nacedero in moderately intensive poultry

production. Experiment in laying quails also showed that it was possible to replace maize by

cassava and 6% nacedero leaf meal (Nguyen Thi Hong Nhan et al., 1997). Growing ducks

performed well when they were given fresh nacedero leaves (about 60-70 g/day) in partial

replacement of soybean meal or fish meal. An increase in skin pigmentation was observed

(Nguyen Thi Hong Nhan et al., 1997; Nguyen Thi Hong Nhan et al., 1999).

C. Digestive Tract of Mallard Duck

The small intestines of mallard were distinctly divided into three segments, namely the

duodenum, jejunum and ileum. The duodenum consisted of descending and ascending limbs

forming U-shaped tube called duodenal loop. The U-shape of duodenum in the current birds was

commonly observed in the other avian species (King and Mclelland, 1984; Bailey and Brown,

1997). The jejunum of the mallard was organized grossly in the form of cone-shaped of spiral

coils. This jejunum shape was similar to other avian species such as domestic fowl (King and

Mclelland, 1984), in most birds (Dyce et al., 2002) and in African pied crow (Corvus albus)

(Igwebuik et al., 2010). The third segment of the small intestine of the mallard was the ileum

which appeared the shortest part of the small intestine.

The structure of bird alimentary system is characterized by large individual variability as

a result of digestive tract adaptation of these animals to environment condition (Szczepanczyk, et

al., 2000). Avian digestive tract modifications may occur as an adaptation to diet (Traveset, et

al., 1998). The small intestine is one organ and it is a primary sit of absorption of the digestive

system for most nutrients in birds and mammals (Lavin, et al., 2010). The animal growth

depends on its capacity to digest and assimilate ingest macromolecules and any impairment of

this is expected to constrain growth (Liu, et al., 2010). The digestive tract is the major site for
digestion and absorption in the body along with being the first site of protection against

exogenous pathogens, making it the body’s largest immunological organ (Choct, 2009). By

interacting with the nutrients supplied by the diet, digestive tract microorganisms have a

significant effect on the host health, nutrition and growth performance (Hashemi and Davoodi,

2011). Phytogenic feed additives improve the gut health of the animal, by controlling and

eliminating pathogenic microorganisms in the digestive tract.

The small intestine is the major site for digestion and absorption of nutrients and is

divided into three parts, namely duodenum, jejunum, and ileum. The crypts depth was correlated

with the intestinal cells turnover rate and the increase in crypts depth indicates the need for

enterocyte replacement and higher tissue turnover (Oliveira, et al., 2009). A high demand for

tissue turnover results in an increase in the energy requirements for maintenance of the digestive

tract (Choct, 2009). The crypt depth may be an important factor that determines the ability of the

crypts to sustain the increase in the villus height as well as to maintain the villus structure (Poole,

et al., 2003). The villi height and crypt depth plays an important role in the digestion and

absorption of feed in the small intestine, as an increase in crypt depth and a decrease in villi

height can lead to increase secretions into the gastrointestinal tract, resulting in a diarrhea,

decrease in disease resistance and a decreased animal performance (Parsaie, et al., 2007; Catalá-

Gregori et al., 2008). the villi crypt ratio of the small intestine plays an important role in the

absorptive ability and digestive capacity of the small intestine (Saeid et al., 2013). Deep crypts

are a sign of a high turnover of cells along the villi, and a high demand on the crypts to produce a

new cell for villi growth (Xu, et al., 2013). The increase of villus height to crypts depth

associated with better nutrient absorption and faster growth (Wu, et al., 2004). The nutrient

absorption is more efficient when villi are organized like this pattern than if they are in parallel
or randomly poisoned (Yamauchi, et al., 1991). (Liu et al., 2010) mentioned that the villi and

crypts play significant role in final stages of nutrient digestion and assimilation.

D. Liver Feature of Mallard Duck

The liver is regarded as an essential and biggest gland of the body, and it plays a crucial

role in numerous physiological processes such as synthesis of blood proteins, production and

secretion of bile, detoxification, nutrients absorption, metabolism of several substances and

storing metabolites (Saez et al., 2012; Odokuma and Omokara, 2015). The bird liver is divided

into two portions forming the right and left lobe (Al-Abedi, 2015). The size or subdivision of

these two lobes can vary among different species. The right lobe appeared in more instance

greater than the left one as in ostrich and bustard (Stomelli et al., 2006; Baily et al.,1997),

however, some species of birds have an analogous size of the hepatic lobes as in galliformes

(Schmidt et al., 2003). Hepatic parenchyma in birds showed similarity with that observed in most

mammals except the variation in some histological characteristics (El-Zoghby, 2005). In coot

birds, the hepatic parenchyma is subdivided into defined lobules and the hepatocytes organized

around the central vein in radiation manner (Selman, 2013).