School Science Lessons
Chicken Project 1
2012-05-12 SPwp
Please send comments to: J.Elfick@uq.edu.au
Table of contents
Preface
12.0 Chicks, care for baby chicks
20.0 Chicken diseases
13.0 Chicken house
2.0 Chicken parts, feathers
1.0 Chicken project management
21.0 Costs, returns and profits
Egg, chicken egg (Science experiments)
8.0 Egg production
2.6 0 Hatching chickens
16.0 Meat chickens, broiler production
22.0 Prepare chickens for food
22.1 Prepare eggs for food
12.0 Chicks, care for baby chicks
12.1 Baby chicks arrive from a hatchery
50.12 Cardboard box incubator
12.2 Caring for baby chicks
12.4 Chicken brooders
9.14 Development of the chicken embryo
9.17 Development of the hatched chickens
12.3 House for baby chicks
9.18 Sex of the chickens
50.13 Styrofoam cool box incubator
50.16 Warm brooder
20.0 Chicken diseases
20.7 Botulism or food poisoning
20.3 Chronic Respiratory Disease (CRD), (mycoplasmosis)
20.1 Coccidiosis
20.8 Fatty liver of laying hens
20.5 Fowl pox
20.4 Lymphoid leucosis
20.2 Marek's disease
20.6 Vitamin deficiencies
13.0 Chicken house
13.1 Cages
13.2 Housing
19.0 Management of deep litter
13.3 Nests
12.3.7 Water reservoir for chicken drinker
2.0 Chicken parts, feathers
12.3.9.1 Chicken bone, Dilute hydrochloric acid with calcium carbonate, (See 2.)
4.0 Digestive organs
3.0 Post-mortem dissection
5.0 Respiratory organs
6.0 Reproductive organs
1.0 Chicken project management
1.1.1 Backyard chickens ("chooks")
14.0 Chicken feed
6.3 Chicken life cycle (Primary)
15.0 Chicken project management
1.3.0 Commercial system
13.5 Laying hens
22.0 Prepare chickens for food, poultry
13.4 Roosters
1.2.0 Semi-commercial system
1.1.0 Village system
8.0 Egg production
9.20 Egg density
8.10 Egg laying
9.10 Egg parts
9.30 Egg preservation (See 6.)
7.2.3 Egg preservation, Waterglass, (See 1.)
13.6 Egg production
9.00 Eggs in your diet
9.40 Float eggs
18.1 Layers, How long to keep layers
17.0 Layers, Management and feeding of laying hens
13.8 Layers, Modern egg laying chickens
13.7 Layers, Point of lay
18.0 Layers, Timing of replacement stock
2.6.2: Measure eggs
22.1 Prepare eggs for food
50.11 Unfertilized chicken egg
2.6 0 Hatching chickens
2.6.7 Care for chickens
2.6.8 Castrated capon raising the chicks as a eunuch mother
2.6.4 Development of chicken embryo
2.6.1 Hatching an egg
2.6.3 Incubators, brooders
2.6.2 Measure eggs
2.6.5 Record chicken development
2.6.6 Sexing a chicken
9.16 Warm brooder
Preface
Before teaching this project, discuss the content of the lessons with a field officer of the Ministry of
Agriculture and get advice on chicken breeds, method of obtaining chickens, site for chicken project,
design of buildings, control of pests and diseases, medicines, feed supplements. Use only the procedures,
medicines and insecticides recommended by the local field officer of the Ministry of Agriculture.
All insect sprays are dangerous. Show the students how to use them safely. Do not get the spray onto
your hands. Do not breathe in the spray. Wash your hands well after using spray. Keep the spray
container in a safe place where students cannot get it. Spray on a day of no wind but if you must spray
when there is a wind, spray down wind. Make sure the spray does not blow on other people.
6.3 Chicken life cycle (Primary)
See diagram 50.6.2: Chicken life cycle | See diagram: 50.6.0: Parts of a chicken
Objective: To explain how the mother hen can make baby chickens.
Discuss the diagram for this lesson with the head teacher before you teach this lesson.
1. Where do baby chickens come from? [Eggs.] Where do the eggs come from? [The mother hen lays
them.] What does a hen need to make a baby chicken? [She must mate with a rooster that will put
sperm inside her to fertilize her egg.] Then she puts a shell around the egg and lays it.
2. Show the children the diagrams and read the explanations. Most fish and all frogs do not look after
their young but chickens always look after their young.
1.0 Management of chicken projects
The three systems of management of chicken projects
1.1.0 Village system
1.2.0 Semi-commercial system
1.3.0 Commercial system
1.1.0 Village system
In this system the chickens are allowed to run all over the village. They are sometimes fed bought feed,
but usually scavenge for themselves and they hatch their own eggs. In other words, the chickens are just
"there" and the owner takes the eggs and meat for his table whenever he wants and whenever they are
available. In this system production is usually very low, mortality rates are very high and it is a very
inefficient method of keeping poultry. However, the advantages are that the owner does not have to
spend any time or money on the chickens and can devote his time to other things that may be more
important to him. Therefore, any methods introduced to improve the efficiency of this type of poultry
keeping must be carefully studied against the owner's desires and the availability of time and money.
Village chicken project
1. Many people like village chickens because they do not appear to need any care. The chickens find
their own food and look after themselves. They hatch out clutches of chickens and some of these
chickens grow up into adult birds. In some villages, chickens can always be found to be killed and eaten.
2. When a hen goes broody, it should hatch many chickens and nearly all chickens should live and grow
to a big size. However, in some villages many chickens do not survive. A village hen may hatch out 10 or
more chickens from her eggs. She then walks about the village with baby chickens following her.
However, after about 3 weeks she may have only a few chickens left because the other chickens have
died. In some villages most of the hens are not laying eggs. Some have stopped laying and spend all day
sitting on their eggs so they will hatch out. Chicken production would increase if most hens were laying
eggs and only a few hens were going broody and sitting on eggs to hatch out chickens. Some have
hatched their chickens and spend all day walking around the village trying to find food. They are not
laying eggs at this time.
3. Investigate what happens to little chickens when the hen takes them to find food in the village. Tie
labels on the legs of the chickens, e.g. label A for a particular hen and labels A1, A2, A3 . . . for her
baby chickens. Note how many village hens are broody and sitting on eggs or broody with young
chickens.
Note how many village hens are not broody. To check whether these hens are laying eggs, catch the hen
and observe whether the lay bones are two fingers apart and the vent (cloaca) soft and moist.
4. Village hens have not been bred to lay eggs. They are descended from chickens that have always lived
in the village. These chickens do not lay many eggs and do not produce much meat. They are small
chickens compared to modern chickens that have been bred to lay many eggs or produce much meat.
Modern egg breeds can produce many eggs but they are expensive, need special imported food and
require much work to look after them properly. The hens of fast growing big meat chickens will not lay
many eggs. Chickens that lay many eggs will have small bodies and not much meat on them. So breed
chickens for egg laying or for growing meat but not both.
5. Put a hen with her chickens in a small yard with a creep in it to investigate how small chickens can be
saved from dying.
5.1 Find a hen that has just started to sit on her eggs. Count the 21 days and be ready to find the hen
when she has hatched out her chickens. Then drive the hen and chickens into the house made for them.
5.2 Find a hen that is walking around the village with many new chickens. Drive the hen and her
chickens into the house made for them.
6. Decide what food to give the little chickens. Imported special food for little chickens called "chicken
starter" may be too expensive for a village chicken project.
6.1 Energy food: Make energy food from grated coconuts or from root crops cooked and grated into
small pieces.
6.2 Protein food: Make protein food from small fish, scaled, boiled until cooked and scraped into small
pieces. Also, use sea cucumbers (beche de mer) small crabs and shellfish and big African snails. Soft
legume plants, e.g. each pea, can be chopped up into small pieces and mixed with other food.
6.3 Vitamins: Some soft green feed should also be cut into fine pieces and mixed with the food.
6.4. Minerals: Get some mineral mixture from the Department of Agriculture and mix the food or mix in a
little salt and a little clean soil.
7. Ask the Department of Agriculture about using a medicine to prevent disease coccidiosis, e.g. drugs
such as Amprolium, Sulfaquinoxiline, or Sulfamezathine. They may be very expensive. Use them for the
first 5 weeks of the chickens' life.
8. When the chickens arrive, put prepared food in the creep. Provide food for the hen and the small
chickens. Keep the small chickens in the house all the time or open the house only in the afternoon to
allow the hen to take the chickens outside to find some food. The hen will teach the little chickens to
find food but the hen must take them back to the house before the night. By the time the chickens are
six weeks old they are bigger and stronger and can look after themselves so can let them go out of the
house.
9. Keep records of the village chicken project:
9.1 Number of chickens put in the project, n1
9.2 Number of chickens were still alive at six weeks of age, n2
9.3 Calculate percentage survival (n2 / n1) × 100,
9.4 List causes of death: disease, eaten by dogs, trodden on by humans, lost in the village, drowned
9.5 List kinds of energy food and protein food given to chickens.
10. Growing village chickens as layers
The cockerels can be killed and eaten or sold in a market. Get more eggs from the village pullets by
giving the chickens some food in the house to get them used to coming to the chicken house. When the
chickens grow bigger, build a bigger creep. Build some nests in the house when the pullets approach 20
weeks of age. They will see these nests when they come to the house to find food. Later when they start
laying as hens they will not have to go searching for the nests and collecting the eggs will be easy. If some
eggs are left in the nest, the hens keep laying and stop them from going broody. Keep some cockerels
with the pullets to have fertile eggs. Modern chickens must be kept shut up in their own separate house
so that so they will not steal the food from the village chickens and not mix with the village chickens and
catch diseases from them.
11. Investigate the habits of village hens
11.1 Note where they lay eggs and how many days after laying before the chickens hatch. (21 days)
11.2 Note the number of hens and roosters in the village.
11.3 Note the colours of the hens and roosters.
11.4 Note how many hens have very small chickens and larger chickens.
11.5 Note how many older chickens the hens have.
11.6 Find a nest where a hen is sitting on some eggs. Note how long the hen stays sitting on the eggs
before she gets up to move around. Note whether the hen has shelter from the rain, protection from other
animals, e.g. dogs.
11.7 Note how many eggs the village hens lay.
11.8 Watch a hen walking with her chickens. Note how often the chickens eat something. Note whether
the chickens stay near the hen.
11.9 Investigate why some chickens die, e.g. run over or squashed, eaten by cats or dogs, drowning,
starvation, disease.
11.10 Note the noise the hen makes to call the chickens or when danger is nearby. Not what happens
when a hen sees a hawk nearby.
1.2.0 Semi-commercial system
A semi-commercial system can achieve an increase in production over that obtained from traditional
village farming if some form of housing and some form of supplementary feeding is available. This system
of poultry keeping requires the chickens to be kept in a house where they are given their supplementary
feed and where they will lay their eggs, until about midday. At midday they are let out to scavenge as
they would in the village system.
In this system the farmer grows either some special feed for the chickens or purchases feed. This farmer
will probably have bought some chickens from a hatchery. They will probably be better quality than
village poultry and have the capacity to produce more eggs or meat. With this system the farmer is trying
to produce more eggs and meat and to be able to sell any surplus to pay for bought feed and the cost of
the bought chickens. The farmer may use this system of poultry keeping to provide protein for the family.
1.3.0 Commercial system
This is the keeping of poultry for business purposes. Most of the eggs and meat are sold by the farmer.
This system of poultry keeping usually fails if the farmer does not have the knowledge or management
ability to make a profit.
2.0 Parts of a chicken and feathers
See diagram 50.6.0: External parts of a chicken | See diagram 50.12: Chicken feathers
See diagram 50.6.5.1: Chicken feathering
3.0 Post-mortem dissection
See diagram 50.6.4: Chicken dissection
Dissect a hen that has a red comb and is laying eggs. Just before the lesson kill the chicken by quick
strangulation, but not in sight of the students who may be offended. Pull off all the feathers then wash
and dry them for later examination by the students. At this stage do not cut the skin. You will need a
piece of wooden board, a hammer, 4 nails about 5 cm long, a new one-sided razor blade or scalpel, a
pair of large straight scissors, string, old newspaper, scrap bucket.
1. Put the chicken onto the piece of board.
2. Study the marks where the feathers were joined to the skin. In some places the skin is bare with no
feathers.
3. Note the pin feathers on the skin. Use a flame to burn off these feathers.
4. Lay the chicken on its back and nail it to the board.
5. Use the razor blade to cut through the skin over the breast bone and down over the thighs. Follow the
lines X-X in diagram 50.6.4.
6. Pick up the edges of the skin and use the razor blade to cut away underneath the skin so you can lift it
off the body. Remove the skin from the whole area inside the dotted lines in diagram 50.6.4.
7. Put the flat palms of your hands on the legs and break the legs down flat. Push down with your hands
until the legs are alongside the body.
8. Make a deep cut with the razor blade through the breast muscle about 2 cm up from the base of the
wing. The lines A and B in the dissection diagram show where to make these cuts. Cut down deep until
you feel a bone, the main wing bone.
9. Use strong scissors to cut through the main wing bone. Cut it on both sides, A and B.
10. Pull the covering of the abdomen out towards you a short distance and make a shallow cut in it but
do not cut the intestines below. Continue this cut along the sides of the body towards the ribs, see the
lines C and D in the dissection diagram.
11. Use strong scissors to cut through the middle part of the ribs where the two parts of each rib meet
at an angle and make a white mark under the skin.
12. Cut right around the sides towards the front of the bird. Lift up the breastbone at the back and push
it up. Use the razor blade to cut the muscles that are holding it down. Cut the breast bone and its muscles
and remove it to reveal the organs of the body underneath.
13. Look in the neck for the windpipe. It is white and has fine rings around it. Follow it down to the
chest where it joins the two bronchi. Look for the narrow parts which make chicken sounds. Cut off the
air tube off and remove it.
14. Lift up the liver and cut underneath it so you can remove it. Do not cut the green gall bladder. Use
scissors to remove the heart then mop up any blood left behind.
15. Look in the neck for the oesophagus. Cut it near the head and tie string around the end. Then follow
the oesophagus to the crop that is very close to the skin, so cut it away carefully. Follow the oesophagus
down to the stomach and the gizzard. Cut off the small red spleen which lies near the stomach.
16. Tie string around the end of the digestive tube near the cloaca to stop the droppings coming out.
Then cut this off between the string and the cloaca.
17. Lift all the digestive organs out of the body and put them on a piece of paper. Pull the intestines
aside so you can follow the tube for its full length.
18. Open the gizzard and observe its strong red muscles and the pieces of stone or sand in it that grind
up the food. Note the intestine, the two blind guts (caecae) and the short large intestine.
19. If the chicken is a male, observe the two large testes.
20. If the chicken is a hen, observe the oviduct. Take out the oviduct and arrange it on a piece of paper.
Note the ovary close to the backbone. Lift up the ovary and cut it away from the back. Pull out the
oviduct to see its parts.
4.0 Digestive organs
See diagram 50.6.3: Digestive organs and trachea | See diagram 50.6.1: Respiratory organs
1. The mouth has no teeth, only a strong beak that can pick up the food. A short tongue has spines on it
pointing backwards. These help to push the food down the food tube.
2. The oesophagus is a long tube that has muscles in its walls. The muscles help to push the food down
this tube.
3. The crop is a part of the oesophagus at the bottom of the neck. It is a place where food can be stored
while the chicken eats quickly. The walls of the crop can get bigger if much food is stored. Hard pieces
of food, e.g. big seeds, are stored in the crop. Here they are softened.
4. The stomach is not very big. When food comes into the stomach, it is mixed with digestive juices that
come from the walls of the stomach. These juices help to digest the food and turn it into a liquid that can
be taken into the body.
5. The gizzard has very strong muscles in its walls. When these muscles work, they squeeze the food and
make it into small pieces. Inside the gizzard is a rough hard lining and sand grains that the chicken has
swallowed. These sand grains and the rough wall help to grind up the food into small pieces. The chicken
needs a gizzard to grind up its food because it has no teeth in the mouth. The muscles of the gizzard
contract strongly once every 30 seconds.
6. After the food leaves the gizzard it goes into the first part of the intestine called the duodenum. Here
it is mixed with more digestive juices from the pancreas and the liver. These juices help to soften and
digest the food.
7. The intestine is a long narrow tube where digested food is absorbed into the blood to used by the
body.
8. The blind gut has two tubes called caecae tied together and joined to the lower end of the intestine.
The food inside the caecae is liquid.
9. The large intestine is very short and contains the droppings.
10. The cloaca is the large opening at the end of the intestine.
11. Droppings are green with a capping of white uric acid and are semisolid. The droppings from the
blind gut are very soft and are only put out once a day.
6.0 Reproductive organs
See diagram 50.6.12: Male reproductive organs | See diagram 50.6.11: Female reproductive system
1. The male chicken is called a rooster or cock. Inside his body are two pale yellow organs called testes
which make the semen. The semen contains tiny sperm which can swim to fertilize an egg by joining with
it. The fertilized egg can grow into a baby chicken.
2. Two small tubes coming from the testes take the sperms to the cloaca where they stay until the rooster
mates with a hen.
3. The female chicken, the hen, has an ovary which makes eggs. An egg is called an ovum (plural “ova”)
and it later becomes the yellow part of an egg, the yolk. In the ovary the ova grow bigger until one of
them is big enough. It breaks out of the ovary and goes into a funnel at the end of a long tube, the oviduct.
In a narrow part of the oviduct the sperms are waiting. One of them may join with the egg and so fertilize
it so that it can develop into a chicken. In the same part of the oviduct two cords, chalaza, are tied onto
the yolk.
4. The fertilized egg then passes down to where the oviduct has thick walls. Here the white of the egg,
the albumen, is put around the yolk.
5. The fertilized the egg then passes down through a narrow part of the oviduct where two thin skins are
formed around the egg. The egg then passes into the shell gland, a tube with thick walls, where the hard
shell is formed around the egg. When the egg is laid, the hen usually sits on it and to keep it warm. Then
a chicken may grow inside the egg.
Teach this lesson during a post-mortem on a hen. After taking out the digestive tubes, take out and the
ovary and oviduct and lay them in a straight line on a piece of paper.
1. Take out the reproductive organs and lay them out in a straight line drawn on a piece of paper.
2. The ovary where eggs are made is attached closely to the back bone of the abdomen. Use scissors to
cut away the ovary to take it out of the body.
3. The yolks have many different sizes. Some are very small. As the yolks grow larger they are inside a
sac covered with small blood vessels to bring food to the yolk to make it grow. At the long space without
blood vessels the yolk breaks out of its sac and starts to become an egg.
4. When a yolk in the ovary is big enough it breaks out of its sac and it goes into a thin funnel that leads
own into a long tube called the oviduct. The egg goes first through a very narrow part of the oviduct
where, inside the egg, two cords are tied onto each side of the yolk. If a rooster has mated with the hen,
sperms will be waiting in this part of the oviduct to fertilize the egg. Later the fertilized egg develops into
a chicken.
5. The yolk then passes for 3 hours down a long part of the oviduct tube where the walls are thick to get
a thick coating of white of egg. Cut open the thick wall with scissors. The egg then passes through an
arrow part of the oviduct for 2 hours where 2 egg skins or egg membranes are added. The egg passes
into a part of the oviduct called the shell gland where it stays for about 20 hours while the hard shell is
formed around it. Cut open the shell gland. If an egg is in the shell gland, take it out to dry. The egg is
dull because it does not yet have a "bloom" on it. The egg then passes through a short narrow part of the
oviduct called the vagina where the shell of the egg is covered with a sticky substance. Later it dries and
makes the shell look shiny, the "bloom" on the egg. The bloom helps to keep out bacteria that might
attack the egg and make it go bad.
8.10 Egg laying
See 2.6.4: Development of chicken embryo
1. Onset of lay or laying
A pullet (poult) is a young hen, 6 to 24 weeks old. Modern chickens do not begin to lay until at least
20 weeks old. Until they begin to lay, call them pullets. Sometimes pullets start to lay in spring when the
days are getting longer. However, close to the equator where there is not much difference in the length
of the day in winter and summer pullets may start to lay in any season. When a pullet starts to lay, the
first few eggs are often very small compare to eggs laid later in the lay period.
2. Clutches
Hens lay eggs in groups called clutches, e.g. a clutch length of 4 means she will lay an egg every day for
4 days. Then she will stop laying and rest for a day before she starts laying the next clutch.
3. Laying cycle
Each egg in a clutch is laid later than the one the previous day. The rising sun in the morning starts an egg
leaving the ovary. If a hen takes 26 hours for an egg to be made and they start the first egg of a clutch at
5 a.m., then will lay the next egg at 7 a.m. the next day. The hen may wait an hour before the next egg
starts being made, 8 a.m. This egg will be laid the following day at 10 a.m. The next egg starts being
made at 11 a.m. and will be laid the following day at 1 p.m. Then the hen will stop the clutch and have a
day of rest, because hens do not lay eggs after 3 p.m. Most eggs are laid in the morning.
4. End of lay or laying
When village chickens have laid about 12 eggs, they will usually stop laying and go broody, sit on the
eggs until they have hatched. Modern egg laying hens do not go broody so easily, but they usually stop
laying in the Autumn when the days are getting shorter. Then they drop many feathers, called moulting.
They will not start to lay again until new feathers have grown. Also, hens may stop laying if they are sick.
9.00 Eggs in your diet
See diagram 50.11: Chicken egg, parts of the egg
The shape of an egg is an ovate spheroid with one end larger than the other end. The egg has cylindrical
symmetry along the long axis. An egg is surrounded by a thin, hard shell. The egg yolk is suspended in
the egg white (albumen) by one or two spiral bands of tissue, the chalazae. The larger end of the egg
contains the air cell that forms when the egg cools down and contracts after it is laid. Chicken eggs can
be graded according to the size of the air cell, measured during candling, e.g. A very fresh egg with
small air cell, grade of AA. As the size of the air cell increases, the grade changes from AA to A to B.
As the air cell increases in size, the egg becomes less dense and the larger end of the egg will rise to
increasingly shallower depths in a bowl of water. A very old egg will actually float in the water and
should not be eaten. In a newly laid egg the yolk is round and firm. As the yolk ages, it absorbs water
from the albumen, which increases its size and causes it to stretch and weaken the clear vitelline
membrane that enclosing the yolk, resulting in a flattened and enlarged yolk shape. The yolk colour is
depends on the yellow-orange xanthophyll pigments in the diet of the hen. Foods containing lutein,
e.g. marigold petals, affect the colour of the yolk. Double-yolked eggs occur rarely in young hens
beginning to lay. Yolkless eggs rarely occur.
Take a fresh egg and a plate into the classroom.
1. People need two main kinds of food, energy foods and protein foods. Examples of energy foods are
rice, root crops and coconuts. Examples of protein foods are fish, meat and other animals, e.g. insects,
snails, frogs and worms. Plants contain some protein especially legumes, e.g. peanuts, beans and peas.
People need protein to make muscle and skin. Children need more protein for every kilogram of body
weight that adults need. Eggs are very good protein food. Both the yellow yolk in the middle of the egg
and the white of egg around it contains much protein.
2. An egg has a pointed end and a round end. The round end contains air. As an egg gets older, the air
increases. Push a pin into this end by making a small hole in the shell. The air comes out when the egg is
put into boiling water to cook it.
3. Break an egg carefully onto a plate. The yolk is the yellow part in the middle. It contains fat and
protein. Some people like eggs where the yolk is a dark yellow colour. Chickens that have not had
much green grass to eat may lay eggs with pale yolks. Sometimes the yolk has a blood spot but eating
it is not harmful. Blood spots may occur when the yolk breaks away from the ovary and starts to turn
into an egg. The white of egg also contains protein. It is usually in two parts. The thick white is next to
the yolk. The thin white is watery and spreads out on the plate. In good eggs have much thick white
and not much thin white. In an egg also see the two cords that connect the yolk to the inside the shell.
The cords hold the yolk in the middle of the egg.
9.10 Eggs parts
See diagram 50.11: Chicken egg, parts of the egg
Study the component parts of a hen's egg and name the parts. Tap a hen's egg against the rim of a dish
so that the shell egg cracks in the middle. Break open the two parts of the egg without using too much
pressure, and lets its contents flow into the dish. Do not break the yoke! The liquid white fills the egg
apart from a small air space. Inside the egg white, note how the albumen filaments, the chalaza, hold the
yellow yolk in the centre of the egg, The germinal disc, from which the chick develops, lies on the yolk
mass. The part of the yolk opposite the germinal disc is the heaviest, so the germinal disc always floats
on the top of the yolk and receives the greatest amount of heat when the hen is sitting on the egg. As the
hen sits on the egg, a chick gradually develops from the germinal disc. During this period, the yolk and
egg white (albumen) nourish it. When, after 21 days, the yolk and the white have been consumed, the
chick is fully developed and hatches out of the egg.
9.20 Egg density
The density of eggs decreases with age because of evaporation of water through pores in the shell.
Evaporation increases with increase in temperature. A new laid egg placed in salt water will sink to the
bottom. A 1 day old egg sinks below the surface, but not to the bottom. A 3 day old egg will sink just
immersed in the liquid. If more than 3 days old the egg will float on the surface. So more shell is
exposed with age
Average relative density
Fresh eggs 1.090
After 10 days 1.072, loss of 1.6% After 20 days 1.053, loss of 3.16%
After 30 days 1.035, loss of 5%
9.30 Egg preservation
1. Dried eggs
Egg powder was produced industrially for the armed forces during the Second World war.
2. "Hundred years old" eggs
Eggs are coated with clay, ash, salt, lime, and straw for long periods. The yolk becomes a green-black
with an odour of sulfur and ammonia compounds. The while the white becomes a dark brown,
translucent jelly with a tasty flavour. The product is usually cut into 4 pieces and eaten raw in Chinese
meals.
3. Pickled eggs
The eggs are boiled then put in a mixture of vinegar, salt, and spices, e.g. ginger, then put in beetroot
juice for colour. The acetic acid in vinegar dissolves the calcium carbonate in the shell. Pickled eggs may
keep for a year without spoiling.
4. Refrigerated eggs
Fresh eggs are preserved by low temperature, cold storage just below freezing point and by excluding
air by coating or immersing the eggs. Eggs preserved by cold storage must be used soon after they
have been removed from storage and thawed. At home, eggs should be kept in the refrigerator, usually
in a rack in the refrigerator door where the eggs can be monitored. Cracked eggs should be discarded
or cooked thoroughly because they may contain disease organisms.
5. Salted eggs
Salt is a good preservative because it draws water out of bacteria and moulds to prevents their growth.
Chinese salted duck eggs are made by immersing in salt water or coating them with salt and mud or
clay paste. The orange-red yolks are solid, but the white is till liquid. They are boiled before being eaten..
6. Water glass
See 7.2.3: Silicon compounds, glass (See 1.)
Water glass is an aqueous solution of potassium silicate or sodium silicate, or a mixture of the two, that
solidifies in the air and seals all the pores in the egg shell and so preserving the eggs. Commercial water
glass is sold as thick syrup liquid and as a powder. Dissolve 1 part of water glass in 10 parts of boiled
water. Pour the solution over the eggs packed in a suitable container and store them in a cool place.
Do not wash the eggs before preserving them because this removes the natural mucilaginous coating on
the outside of the shell. To prevent the shells of eggs preserved in water glass from cracking when
boiled, puncture the blunt end of the egg with a pin before putting it into the water.
9.40 Float eggs
Estimate the age of an egg by floating. Place a fresh egg in a solution of 1 part of salt to 2 parts of water.
From 1 to 36 hours old, the egg sinks completely, lying horizontally on the bottom of the container.
After 2 to 3 days, the egg sinks to just below the surface of the water, with a slight tendency of the large
end to rise. After 5 days the long axis of the egg floats at 20o from the perpendicular. After 8 days 45o.
After 14 days 60o. After 21 days 75o. After 30 days 90o, so the egg floats upright with the point or
small end downward. The change in floating action is caused by the air cavity in the big end of the egg
increasing in size and capacity as the egg grows older.
12.0 Care for baby chicks
12.1 Baby chicks arrive from a hatchery
See diagram 50.6.5.1: Chicken feathering record
1. When the chickens arrive, collect the chickens, open their box and give them some food and water.
2. Record number of chickens, date of arrival, number died before delivery, number of sick chickens
on delivery, colour of feathers, colour of beaks, colour of eyes.
3. Note whether all chickens are eating. If not, tap on the food container with a pen. The chicken will
think it is the sound of the hen's beak and it will start eating.
4. Note whether all chickens are drinking. If not, catch a chicken and gently push its beak into the
water to make it drink.
5. Study the chickens carefully. Note the number of toes, earlobes, wattles, any sign of a comb and any
abnormal features, e.g. twisted legs.
6. Note the colour and size of the first droppings.
7. Record any feathers on feathering records.
8. Note whether the chickens move about or stay together in one place, where do they go, the sounds
they make and how they drink.
12.2 Caring for baby chicks
See diagram 50.6.9: Pick up baby chicks
Hold a chicken safely. Hold the legs between the last 2 fingers of the right hand.
1. In some villages the people are not accustomed to caring for chickens.
Make a roster and put down the names of four students for each day to go to the brooder twice every
day and do the following:
1.1 Replace newspaper covering the floor.
1.2 Empty the drinker. Clean it with running water. Fill it with clean water again.
1.3 Add food to the feeder.
1.4 Study each chicken carefully. Look at the droppings. If the students see anything that is not right
they should tell the teacher straight away. Every 5 days, record chicken weights and how many feathers
are showing.
2. Prevent little chickens from dying when they are young. Some chickens may be killed by hawks, or
cats, dogs or other animals. Some chickens die because they get a disease. Some little chickens die
because they do not get enough energy food and protein food. However, if some food is put out for
them to eat, dogs or big roosters and hens may eat the food and chase the chickens away. 3. Choose a
dry place to make the yard. Put a fence or wall around the yard to keep other chickens and animals out.
Put in strong posts for the house. Make walls and roof for the house. Build a creep in the middle of the
house with a cover that can be taken off to put food inside it. Make a protected place where the hen
can sit on her chickens. Use a creep to stop dogs and the big chickens eating the food for little chickens.
A creep can be a small area surrounded by small sticks pushed into the soil. The sticks are so close
together that dogs and big chickens get inside this place but small chickens can. Make a cover over the
creep to keep out dogs, other chickens and rain. Build the creep under a roofed pen so the hen and her
chickens can be put inside the pen until the little chickens learn to find the food in the creep. The food
for the small chickens should be in very small pieces. The wall of the feeder must not be too high for
little chickens to eat out of it.
4. Feeding young chickens
Day old chickens for meat or egg production require a 20% protein feed. The feed contains a
coccidiostat to prevent coccidiosis disease. When buying feed for chickens, check the label on the bag
to see whether the feed is medicated with a coccidiostat. Feed the chickens the 21% protein medicated
feed for the first six weeks. If raising meat birds, then keep feeding this feed until the chickens are 9- 10
weeks of age when they will be sold at the market. If raising pullets for egg production, at the end of six
weeks change the feed to a grower feed that contains only 15% protein. Use the lower protein feed to
save costs and to delay the maturity of the chicken when it starts to lay eggs. By delaying maturity, the
chicken will produce larger eggs when it starts to lay at about 24 weeks. If a chicken is made to lay
eggs at too young an age, most of the eggs it will produce during its life will be small eggs. If the price
received from small eggs is not as much as that received for large eggs, the more large eggs the greater
the profit. Commercial poultry keepers, usually buy feed because they do not have enough time to grow
feed crops.
12.3 House for baby chicks
See diagram 50.6.6: Make a chicken house | See diagram 50.6.7: Make a chicken surround
The house must have the following:
1. The house must be dry. It must have a roof and good walls that keep out the rain. Air vents in the
walls must have hoods over the top of them to keep out the rain.
2. The house must be cool. Do not use iron for the roof or walls. Use materials such as palm thatch that
allows air to flow through it. Do not use plastic sheeting for the walls of the house, because no air flows
through it.
3. The house must be safe to protect the chickens from cats, mongoose, owls, dogs and human thieves
who may steal the birds. Predators can be kept out by putting wire netting or loose bamboo strips over
all the holes. The only way to keep out thieves is to put a door on the house and put a lock on this door.
4. The house must have enough space. Laying hens need to have more space than meat chickens.
Twelve hens need 4.4 m2 of floor space. A house 1½ m × 3 m, or 2 m × 2 m enough floor space for
12 hens.
5. The house must have perches. Each chicken needs 23 cm of perch length. So if the house is two
metres long, use 3 perches two metres in length along one wall.
6. Cover the floor of the house with deep litter and put the chickens in a round “surround” with no
corners where for the chickens can huddle together and smother. Use a 2 metre surround for 250 to
300 chickens. Keep the chickens confined for the first two weeks close to their source of heat, feed
and water. After two weeks gradually increase the area until at four weeks they can use the whole floor
area of 100 cm2 per chicken. You can remove the surround after two weeks, but block of the corners
of the house to prevent crowding.
12.4 Chicken brooders
See diagram 50.6.3.1: Simple electric incubator | See diagram 50.6.3.2: Warm brooder
See diagram 50.6.3.4: Electric incubator | See diagram 50.6.3.3: Brooder drinker
See diagram 50.6.3.5: Feeder box
Chickens require a uniform temperature for the first six weeks of their life. In nature the warmth of the
hen's body gives the chicken enough heat, but when chickens are raised artificially a source of heat
must be provided for them. This is most economically provided by warm earth brooder or kerosene
lamp. 1. Make a brooder to be ready before the modern laying chickens arrive. Use it for the first 2
weeks. You can make two kinds of brooder:
1. Make a cold brooder from a cardboard carton or a box 76 cm long and 37 cm wide to hold 12
small chickens. The chickens can keep warm for the first 10 days of their life by moving between strips
of old blanket fixed to the roof at one end of the brooder. Put the feeder and drinker at the other end o
f the brooder. 2. In a hot brooder the heat is provided by a kerosene lantern turned down low. The
brooder must be big enough so that chickens can move away from the kerosene lantern if they find it
too hot.
2. Make drinkers from two tins of different sizes. The smaller tin has a small hole made with a nail down
near the open end. This hole must be below the edge of the larger tin. The larger tin is cut down to 4 cm
deep.
3. Make a feeder from a chalk box so that chickens cannot stand in the food. In warmer coastal places
the easiest method is by using a kerosene lamp and a sheet of 3-ply timber. Cut a hole is cut in the
middle of a 112 cm × 112 cm piece of plywood for the lamp. The brooder should be 15-20 cm high
from the floor. Light the lamp at about five o'clock in the afternoon. Nail pieces of bag 5 cm wide onto
the 3-ply timber to keep the heat in and allow the chickens to go in and out. In cooler highlands places
so plenty of heat must be provided to keep the chickens warm. The ideal temperature for a brooder is
35oC measured just inside the brooder and 2. 5 cm above the floor. If you do not have a thermometer,
judge the temperature by putting a hand inside the brooder. If the temperature feels pleasantly warm,
the temperature is right for the chickens. If it feels hot, turn down the wick of the lamp.
4. A warm earth brooder is suitable for large numbers of chickens. You need a special house for this
brooder, with a low ceiling, about 120 cm high. Bury a 44 gallon drum half way into the earth. Make a
chimney, a vent for air and a hinged lid so wood can be put on the fire. Provide protection around the
drum so that the chickens cannot burn themselves on the hot drum. Light the fire in the afternoon and adjust the air vent so the fire will burn all night. This brooder is useful for the colder highlands.
13.0 Chicken house
See diagram 50.6.6: Chicken house | See diagram 50.6.10: House door end
See diagram 50.6.9: Feeder height | See diagram 50.6.3.3: Chicken drinker
The house needs have only 0.25 m2 per bird. It should be made out of bush materials. For 10 hens and
one rooster, the house would be 1.5m × 1.5 m, have three nests, roosting space and a feed trough and
a water trough made with bush materials, e.g. bamboo. The house should have a big roof overhang and
a deep drain around the building to stop water getting in. Cover the floor with deep litter material,
e.g. chopped dry grass, coffee skins, rice husks.
13.1 Cages
When the pullets start to lay, some people prefer to put them into laying cages instead of leaving them
on the floor.
1. When you leave hens on a floor, they will form a social order and peck the lowest hens in the social
order so much that they get worried by the pecking and they do not lay as many eggs. If you put each
hen into a separate cage then no hens will be worried by pecking.
2. When hens are put into separate cages, each hen has its own food and water so you can be sure that
each chicken gets enough food.
3. When a hen lays an egg in a separate cage, it rolls down in front of the cage where it is easy to collect
and then hen cannot peck at the egg and eat it. Also you can tell which hens are not laying.
Cages can be made with wire netting placed on supports so they are chest high. The droppings fall onto
the ground under the cages. Instead of wire netting you can use bamboo sticks to make cages.
3.1 Put two rows of posts 48 cm apart in the ground with one row 6 cm higher than the other row. The
pairs of posts are 25 cm apart in the rows. Use string to make sure that the posts in each row are all the
same height. Build a framework for the cages with squared timber. To make 24 cages, use eight pieces
2½ ×x 5 cm × 3 m, six pieces 48 cm long, 26 pieces 73 cm long, 52 pieces 42.5 cm long. Nail down the
73 cm long narrow floor pieces of split bamboo with the round side up. They must stick out of the cage
on the lower side. Leave a space of 1.3 cm between each of the floor strips. This makes a tray so that
the eggs roll down into this tray and stay outside the cage. The small spaces between the floor pieces let
the droppings fall down to the floor. Put on the sides between the cages using pieces 2.5 cm apart, close
enough together to stop a hen putting her head through it to peck the hen in the next cage. Fix pieces of
split bamboo to the front and back of each cage about 7 cm apart so the hen can put her head through
them to eat or drink. Leave a space 6 cm at the bottom of the front side so the eggs can roll out of the
cage. Make a lid for the top of each cage from thin pieces of whole bamboo. They must be round and
7 cm apart so the hen can put her head up through the lid without getting cut by the sharp edges of split
bamboo. Tie the lid to the top of the cage with string. Do not use nails. Fix food and water troughs to
the front and back of each cage.
4. In commercial operations, the cages are kept in long sheds, tunnels, and air is pushed through the
tunnels by large fans.
5. Some people object to commercial "factory farming" using cages because they say that the natural
behaviours are prevented by over-crowding, e.g. flapping wings, dust bathing, scratching, pecking,
perching and nest building. Also painful de-beaking operations may be used to stop cannibalism. The
European Union is expected to ban battery cages for egg laying hens from 1 January 2012 but some
member states have suggested alternative actions to prevent cruelty but preserve the intensive egglaying
industry.
6. People who object to "factory farming" prefer "free range" laying hens that are given uncrowded
outdoor access. However, the term "free range" has no definition within commercial production industry.
The unpredictable diet of free range hens will produce unpredictable eggs.
13.2 Housing
Layers can either be housed on deep litter or be allowed to run outside. If they are fed properly, you
can to keep them on deep litter. If they outside they may be killed by dogs or infested with worm
internal parasites that lower their production and affect their health. On a commercial poultry farm,
keep the chickens on a deep litter floor. Management of the laying hens is very easy if they are on deep
litter because you only have to feed and water them daily. Keep the feed and water troughs clean. Rake
over the deep litter material two times a week. Collect the eggs twice daily, at 11 a.m. and 3 p.m. so
that there will be less broken eggs and hens will be less likely to start eating their own eggs. If you see
any sick birds, remove them immediately from the house. The hen prefers a comfortable and relatively
dark place with sawdust, coffee skins or soft grass in the nest to lay her eggs on. Provide one nest for
every 4 birds. The nest should be placed about 45 cm above the ground. You can use a four gallon
kerosene tin with half of the top cutout to make a nest.
Find a hen that will soon hatch out her chickens or has just done so. Find the place the hen chooses for
making a nest. Look for nesting places that hens have chosen. Hens like the nesting place to be a little
dark. They do not like too much light. They like places with a small entrance and more room inside.
They do not mind if they have to push through some leaves or grass to get inside the nest. They like to
have some cover over their heads when they sit on the nest. They do not like strong sun shining on them
or rain falling on the nest. Hens like the nesting place to be a private and that they cannot be seen easily.
Hens like nests is low down or right on the ground. Hens like the nest to be comfortable with soft litter in
the nest. Make a place where hens can pick up small pieces of stick or grass or feathers. They like to
pick up these things in their beaks and put them on their backs. If you are making a nest, then you can
put some of these small things around the nest. It must be in a dry place. If the ground is in a hollow or
low place, then the level of the soil can be built up. To make the hen go broody, put a nest egg in the
nest. When hens they are looking for a place to make a nest they like isolation, darkness, head cover,
small entrance, low level, comfortable, small pieces to pick up and dryness.
13.3 Nests
At about 20 weeks of age, you must provide nests for the pullets to start laying. Hens like nests to have
the following features:
1. be dry
2. be a little dark. with a small entrance
3. have head cover
4. be isolated from other objects in the house
5. be low down
6. be soft so that a hole can be scratched in the middle of the nest
7. have small pieces of grass, feathers or stick, close to the nest that the hen can pick up in her beak
8. have a hole at the back to give air flow through the nest.
Sometimes you can help a pullet to start laying if you put in the nest a china egg or a round stone about
the size of an egg. Place the nests up against the wall of the house in a corner. Never use steel or iron
drums for making a nest because they get too hot on hot days. Provide one nest for every 4 or 5 hens.
So for 12 pullets, you need 3 nests in the corner of the house.
Three types of nest:
1. Take out one of the narrow side boards of a wooden box. Cut apiece off it and put it back to make
a support to hold the nest material in place. Use wood to cover up half of the open side and make a
small entrance. Cover any gaps between the boards that let in light with using bags to make the inside
darker. Put soft grass material inside the box and small pieces of grass just outside the nest. Make a
small hole in the back so that cooling air can flow through the nest.
2. Use a cardboard carton from a store. Cut away part of a side. Make a hole in the back for
ventilation also.
3. Use 4 strong sticks about 60 cm long. Sharpen the ends and drive them into the ground close to the
wall so that their tops are close together. Tie the tops together firmly with string. Put a cover over the
sticks but leave 2 holes, a big hole on one side for the hen to enter and a small hole on the other side for
air flow. To cover the sticks use thatch, paper, cardboard or woven wall materials.
13.4 Roosters
Roosters are not necessary for hens to lay eggs. They are only necessary only if you want to breed
chickens. If the chickens are kept only to sell their eggs, then they will lay more eggs if there is no rooster
kept with them. Roosters are not necessary for chickens to lay eggs. Male birds of a laying breed are
usually not used for meat production so are usually culled at the hatchery. Fertilized eggs will stay fresh
for only three days, but unfertilized eggs will stay fresh for at least a week.
13.5 Laying hens
Laying hens require 0. 25 m2 of floor space if kept in a deep litter pen. Provide roosts, egg nests and
clean water. Feed green feed once a day. Provide a box of crushed coral or shell grit for the chickens
to peck to so that they get plenty of calcium to make the egg shells strong. Also, provide hard grit or
very small stones in a separate box for the birds. Poultry do not have teeth so they eat hard grit that is
held in the gizzard to help grind the feed. The chickens are fed a16% layer ration in a self-feeder once a
week. As with chickens and growers, turn the deep litter material once a week. The nests must have
clean grass or coffee hulls in them that are changed every 2 weeks. If you see clucky or broody hens,
i.e. chickens that sit on the eggs to hatch them, put them in a separate wire cage for three days.
Good layer management requires the following:
1. Give correct feed. Use a creep to give food to small chickens.
2. Make clean water available at all times.
3. Make green feed available once a day.
4. Make shell grit and hard grit available in separate boxes.
5. House must be waterproof and free of draughts.
6. Plenty of roosting space and nests are necessary.
7. Turn deep litter once a week.
8. Nesting material must always be clean to keep eggs clean.
9. Collect eggs twice a day.
10. Cull layers at 18 months of age. Commercial producers may cull between 100 – 130 weeks of age,
when their egg productivity starts to decline.
11. Keep the layer house away from the young stock shed.
12. Clean houses out thoroughly before putting in new stock and rest for three weeks.
13.6 Egg production
1. Hens will lay 160-240 eggs in twelve months.
2. Losses from day old to 18 months should not be higher than 15-20% for the business to be economic.
3. Pullets will start laying at 24-26 weeks of age.
4. As a rough guide for budgeting for layers, the sale price of ten eggs should be ten times the price of
0. 5 kg of layer feed, e.g. 0. 5 kg of feed costs six cents, therefore the sale price of ten eggs should be
60 cents.
5. Stop hens going broody and always sitting on their nest. A hen goes broody is when she can feel
many eggs underneath her or see many eggs in the nest. The feathers of the broody hen are fluffed out
and she makes a clucking noise. So you can stop hens going broody if you collect the eggs from the
nest. However, village hens may hide their nests and make nests the same colour as the grass and the
ground so and seeing them is difficult. Never take all the eggs away from a nest because if a hen comes
back to her nest and finds that all her eggs have gone, she may leave that place and make a nest in
another place. So leave three eggs in the nest. you can use some China eggs or you can put a
mark on 3 eggs so you will know which ones to leave each time.
6. You do not want to eat an egg that has started to turn into a chicken. As an egg starts to turn into a
chicken, the bubble of air at the round end gets bigger and the egg floats. If you put eggs into a bucket
of water, the fresh eggs will sink to the bottom, but eggs with a chicken inside, or bad eggs, will float.
13.7 Point of lay
1. The first eggs laid by pullets are usually very small. There is nothing wrong with this. Larger eggs will
soon be laid. There may be no small eggs laid if the chickens have not been given all the food they need.
Restricted feeding is sometimes used to help stop Marek's disease. The chickens start laying later than
22 weeks, but the first eggs are usually big.
2. Record the age of the pullets when they started laying.
3. Hens cackle after laying an egg, so this the sign that they have laid. It is also a sign to any roosters that
they are again ready to mate.
4. Record the clutch length of a hen. Mark a certain hen and record the times when she lays an egg on
two successive days. Usually the second egg will be laid about 26 hours after the first egg. Then calculate
the clutch length because no eggs will be laid after 3 p.m.
5. Collect and record the eggs taken from each nest.
13.8 Modern egg laying chickens
The White Leghorn breed is all white and has a small body, with a big red comb. Some may have
patches of black or red colour and white because they are crossbreed hybrid laying chickens. These
chickens can lay many eggs when they grow bigger, but they must have good food and good care.
They need much more care than the village chickens. They will need their own house with a roof and
fence, a brooder, feeders and drinkers, a creep, nests, good food. When the little chickens arrive, give
them food, water and shelter. Imported chick food is expensive but makes the chickens grow quickly.
The chickens will arrive in a box but you have no hen to care for them. So you must make a brooder
where the chickens will be warm and be cared for during the first 10 days. After the chickens leave the
brooder, they must grow to a big enough size before they can start to lay eggs. you may need to care for
them for 20 weeks before they are ready to start laying. In places where the difference between the
length of the day in winter and in summer is large, the hens start to lay best in the spring when the length
of the days is getting longer. However, in tropical countries the length of the day does not change very
much and pullets will start to lay any time.
14.0 Chicken feed
This system requires high protein feed. When the chickens are out scavenging in the afternoon, they will
find some feed. However, most of it will be of a carbohydrate nature that is low in protein and unless
they are fed a high supplement their production will be low. Either buy a high protein feed, e.g. protein
concentrate or meat meal, or grow a high protein feed, e.g. soybean. Buying high protein feed is easier,
but it may be expensive. Mix the high protein feed with cooked sweet potato, taro, yams, or grain,
e.g. sorghum or corn, in equal proportions so that each chicken receives 56 g of feed per day, i.e. 28 g
of high protein feed and 28 g of other feed. Fed in this way, a 50 kg bag of high protein feed would last
eleven chickens 51/2 months. The sale of one egg per day from the project might cover the cost of the
bought feed. Using this type of feeding expect about three eggs per day from ten hens. If growing feed,
you must estimate how much feed you need to grow. An adult chicken will eat 110 g of feed per day,
and although the chickens will be outside scavenging for 4-5 hours per day you must still provide this
amount of feed. At 110 g of feed per day the eleven chickens will eat 1.25 kg feed per day, i.e. 8.75 kg
per week or 455 kg per year. Below are some suitable mixed rations for this system, provided the
chickens can run outside for 4-5 hours every day.
1. Crushed grain 64, Dried green feed 5, Peanuts 21, Concentrate 10, Total 100 kg
2. Crushed grain 79, Dried green feed 10, Concentrate 11, Total 100 kg
3. Crushed grain 60, Crushed peanuts 40, Total 100 kg
4. Crushed grain 70, Crushed soybean 30, Total 100 kg
Cook soybeans and peanuts for twenty minutes and then dry them before mixing into the ration.
15.0 Chicken project management
Daily:
1. Feed and water the birds.
2. In the afternoon, clean both the feed and water troughs.
3. Collect the eggs.
4. Let the chickens out at 12 o'clock.
5. Lock the chickens up at night. Twice a week:
6. Rake over the deep litter and replace any wet litter.
7. Clean out nests and put in fresh nesting material.
Yearly:
1. Thoroughly clean out the house.
2. Take out the deep litter and use on a vegetable garden.
3. Put in fresh litter.
4. Sell the old chickens and replace with young chickens that have been either bought or reared in the
village. Cull by selling or eating the laying stock at 18 months of age, i.e. after they have been laying
eggs for 12 months. If chickens are kept longer than 18 months, it will cost more to feed them than the
money the owner receives from the sale of eggs.
Time the replacement of his laying stock so that they will start laying eggs at the time that the layers have
reached 18 months. To be ready at the right time, the replacement stock must be bought as day old
chickens when the laying stock is 12 months old.
5. Make any necessary repairs to the house.
Commercial meat production
Use commercial poultry breeds because of the high cost of food. Get as many eggs as possible from the
chickens by using good quality stock. Hybrid chickens can only be used commercially to produce meat
or eggs. The eggs or chickens of commercial breeds must not be used for hatching or breeding. So
commercial breeds must be replaced as existing stock become old. Hybrid stock is used for commercial
poultry farming because their production is much higher than the ordinary pure breeds, e.g. White
Leghorn.
Care of growing chickens
1. Make sure there is enough dry litter on the floor for the chickens to walk on. There should be no smell,
because the dry litter will absorb the moisture in the wet droppings.
2. Make sure chickens have enough to eat. Start to use a bigger kind of feeder hung from the rafters and
is raised as the chickens grow. It should be raised so that the top edge of the feeding tray is the same
level as the shoulder of the chickens. For older chickens feeders should be set level with their shoulder
height.
This feeder can be made from an oil drum that has been washed out or a box.
3. Make sure the chickens have enough water to drink with a coccidiostat added to it.
The 5 things needed in a good chicken house are dry, cool, safe, perches, enough space.
The sign of coccidiosis disease is blood in the droppings.
12 laying chickens need 4.4 m2.
Never use iron or plastic sheeting when making a chicken house.
16.0 Meat chickens, broiler production
See diagram 50.6.7: Plan of house for broiler production
Most poultry meat production will be for the “live” market and will be sold through the village market.
Meat chickens reach a marketable weight at 9-10 weeks. To increase profitability, sell all the chickens
at the same time. So raise only the number of chickens that can be sold at the same time, e.g. 25-30
chickens. If you keep the chickens longer than 10 weeks, it could cost more to feed them than the extra
money received from their sale. Broiler housing
A chicken needs a floor area of 0. 1 m2. Build the house with bush materials with a large roof overhang
and surrounded by a deep drain to keep out any water. Throw the earth from the drain inside the house
and compact it until it is very hard. This action raises the level of the floor to ensure that no water comes
inside. Cover the floor with 15 cm of deep litter material. Put feed and water troughs in the house to allow
56 cm of feeding space per ten chickens and 28 cm of watering trough per ten birds. Broiler management
Use only meat strain chickens for meat production because they can produce more meat for how much
feed eaten. If you buy unsexed chickens, you can raise both pullets and cockerels for meat production.
Buy the chickens as day old chickens. Broilers must grow as much meat as possible in as short a time as
possible. Feeding broilers differs from feeding pullets because broilers must be fed a high protein diet for
the nine weeks it takes to raise them. Feed broilers a 20% protein medicated feed which has to be bought.
Feed and water must be always available and must never run out. If their growth rate becomes slower, the
result will be less profit for the farmer. After keeping broilers on this feed for the whole period, sell them
when they reach 1, 6 kg live weight. Some chickens will grow faster and may be sold in the eighth week,
but all chickens must be sold by the tenth week.
Daily management
1. Fill feed and water troughs three times a day.
2. Clean water troughs daily.
3. Rake over deep litter daily.
After each batch of chickens
1. Remove all deep litter and put on to a vegetable garden.
2. Thoroughly clean all feed and water troughs.
3. Spell (rest) the house for three weeks between batches of chickens.
17.0 Management and feeding of laying hens
The laying hen requires a 16% protein food and a well balanced ration called a layer ration. The
following are some of the suitable feed mixes:
1. Feed mix: Grain (wheat, rice, corn (maize) or sorghum) mixed with poultry concentrate
All the necessary minerals, vitamins, proteins and carbohydrates are balanced when poultry
concentrate is used, but it costs more than if you grow the feed plants.
Rations using imported concentrate and locally produced grains
.
 Starter / broiler
ration (20%) 		Grower
ration (15%)		 Layer
ration (16%)
Grain 70 kg 80 kg 71 kg
Poultry concentrate 30 kg 20 kg 29 kg
Total feed 100 kg 100 kg 100 kg
2. Feed mix: Use home grown soybeans and grain
The vitamin supplements are usually not expensive. Rations using locally grown feeds
.
 Starter / broiler
ration		 Grower
ration 		Layer
ration
Soybeans 30 kg 10 kg 20 kg
Meat meal 10 kg 10 kg 9 kg
Grain 60 kg 80 kg 71 kg
Vitamin
supplement		 40 g 40 g 40 g
Salt 225 g 225 g 225 g
3. Feed mix: Grow sweet potato and mix it with poultry concentrate
Sweet potato is very low in protein and the chickens will not grow or lay eggs if fed sweet potato only.
Feed needs for one chicken for the different ages:
Concentrate / sweet potato rations for different ages of poultry
The figure in the concentrate and sweet potato column is the amount of feed each chicken will eat for
that period of its life.
Age of bird Concentrate
(kg)		 Sweet potato
(kg)		 Total
(kg)
0-6 weeks
(+ broiler ration)		 0.30 1.50 1.80
6-26 weeks 1.90 17.10 19.00
6-18 months 8.60 77.50 86.10
4. How much feed to give to ten chickens each day. The sweet potato is cooked and then mixed with
the protein concentrate.
Feed needs for a 10 hen layer enterprise feeding concentrate and sweet potato
Age of Bird Concentrate Sweet Potato Total
0-6 weeks (+ broiler ration) 70 g 340 g 410 g
6-26 weeks 160 g 1.43 kg 1.59 kg
26-78 weeks 2.30 g 2.13 kg 2.36 kg
5. Feed consumption rates for grain rations 1
Week after hatching 100 chickens will eat
1st week
2nd week
3rd week
4th week 		4.50 kg feed
9.0 kg feed
13.5 kg feed
8.0 kg feed
6. Feed consumption rates for grain rations 2
Total Feed Consumption 100 chickens will eat
To 4th week
To 6th week
To 8th week
To 12th week
To 24th week
 45.4 kg feed
95.3 kg feed
163.4 kg feed
345.0 kg feed
908.0 kg feed
7. Spaces and roosts
_
 0-4 weeks
 4-10 weeks
 10-20 weeks
 Adult chicken
Floor space
(m2 per bird)		 0.05 0.1 0.25 0.4
Feeding space
(m per 100 birds)		 1.8 3.0 4.26 6.0
Water space
(m per 100 birds)		 0.6 0.9 1.8 2.4
Roosts
(m per 100 birds)		 .
 9.0 15.3 18.0
Modern chicken rations contain every kind of food needed by the birds:
1. Energy food, e.g. wheat meal.
2. Protein food, e.g. fishmeal or meat meal. They may also contain extra parts of proteins called amino
acids, e.g. lysine.
3. Vitamins, including vitamin D if the chickens cannot get sunshine.
4. Minerals.
5. Medicated rations, e.g. drugs to prevent coccidiosis disease.
1. "Chicken starter" for very young chickens contains a good energy food and about 21% protein for
meat chickens or 20% protein for egg breed chickens. Chicken starter is so rich in protein that it is the
most expensive to buy but it can be used for only the first four weeks then changed to "chicken finisher",
or "grower ration".
2. “Chicken finisher”, or “grower ration” is used for growing meat chickens, called broilers. The protein
percentage is about 18%. It can also be given to laying pullets but they are usually given a ration with less
protein, e.g. 17%.
3. "Laying ration" is for laying hens and contains at least 16% of protein.
4. If buying modern chicken rations for the first time, buy a small quantity of chicken starter to give the
chickens a good start then change to local rations at 4 weeks of age. The starter ration should be
medicated to prevent coccidiosis disease.
18.0 Timing of replacement stock
Cull (sell or dispose of) the laying stock at 18 months of age, i.e. after they have been laying eggs for
12 months. If chickens are kept longer than 18 months, it will cost more to feed them than the money
received from the sale of eggs. Time the replacement of laying stock so that they will start laying eggs
when the layers have reached 18 months of age. As it takes a chicken 6 months, i.e. from day old to 26
weeks, to be raised before it starts to lay eggs, the replacement stock must be bought as day old
chickens, when the laying stock that the owner has on his farm are 12 months of age. If he buys his
replacement chickens at this time then they will start to lay eggs just as his present layers turn 18 months
of age and so his cash income will not be interrupted: You can see from the table how to time the
replacement stock to replace the old layers, without interrupting egg supply.
Start batch 1
 6 Months
 12 Months
 18 months
 .
 .
Day old chicks
 Start laying
 Buy replacements
 Cull layers
 .
 .
.
 .
 Start batch 2

 6 Months
 12 Months

 18 Months
.
 .
 Replacement
day old chicks
 Start
laying
 Buy replacements

 Cull
layers
.
 .
 .
 .
 Start batch 3 6 Months
.
 .
 .
 .
 Replacement
day old chicks		 Start laying
18.1 How long to keep layers
Hens may keep on laying well for a while but they will certainly go out of lay. After having a rest the
hens will start laying again for a second year. However, in the second year the hens do not lay as many
eggs as in the first year. Usually they lay between 60% and 75% of the first year of laying. However, it
is best to keep the hens for a second laying season because they will not lay any small eggs in the
second laying season and
if there has been a lot of Marek's disease this will have been mostly in young birds. Chickens more than
one year old are less likely to die from Marek's disease.
19.0 Management of deep litter
Deep litter is any dry material such as coffee mill hulls, rice hulls, peanut hulls, sawdust, dry leaves,
wood shavings, finely chopped dry grass. When it is placed on the poultry house floor, it combines with
the birds' droppings and undergoes a bacterial process which gives sanitary non-smelling conditions
when handled correctly. This may sound like a lot of work for the project owner, however, very little
work is required to look after it properly. There are three things that have to be remembered:
1. The shed must be kept dry. The roof must be rain proof and the overhang of the roof must be enough
to keep the rain from blowing in. Drinking water must not spill onto the litter.
2. The shed must not be overcrowded. Note the floor space needs for various ages of stock. If
overcrowded, litter becomes hard and disease could be introduced to the house.
3. Turn the litter once a week and rake over to stop it going hard and to mix the birds' droppings evenly.
Advantages of Deep Litter
1. Chickens burrow into the litter and cool themselves as the litter maintains a uniform below air
temperature in hot weather.
2. Chickens burrow into the litter and warm themselves as the uniform litter temperature is above air
temperature in cold weather and the litter acts as an insulation against the cold.
3. Chickens scratch in the litter which gives them something to do and so stops feather picking, egg
eating, and gives them a “dust bath” which controls lice. Deep litter also provides some vitamin B12.
The droppings combine with the litter and bacterial action ensures that no smell develops and no flies
breed in the dry deep litter. Deep litter is a valuable fertilizer. One 3 m × 3m house with 25 hens will
produce in one year 3/4 tonne of deep litter fertilizer. This will contain the equivalent of 112 kg
ammonium sulfate, 100 kg superphosphate, 35 kg potassium, 5 kg magnesium 5 kg sodium 20 kg
calcium plus trace elements. It is a valuable by-product of the poultry project.
20.0 Chicken diseases
Some diseases can kill chickens, e.g. coccidiosis and Marek's disease. Other diseases may not kill
chickens but they cause them to produce less, e.g. Mycoplasmosis, Infectious bronchitis, and Newcastle
disease. The following are important diseases.
20.1 Coccidiosis
It is caused by single celled parasites that live in the gut wall. Coccidiosis is spread when one chicken
eats faecal material, droppings, from an infected chicken which contains small egg-like bodies called
oocysts. Oocysts can remain alive in poultry sheds for more than a year. It is impossible to prevent this
spread unless chickens are housed so that they have no contact with faeces. Affected chickens become
depressed, lose condition and are very pale. The feathers are ruffled and the wings droop. There is
usually diarrhoea and blood in the droppings. They may not eat very much and very often they die. The
coccidiosis parasite needs moisture to become infectious so the litter must be kept dry, ventilation must
be good and the chickens should not be overcrowded. Effective live vaccines and drugs called
coccidiostats are available. Coccidiosis may occur if the level of coccidiostat in the feed is too low, if the
chickens are not eating enough or if the coccidiostat is withdrawn too early before immunity has
developed. Put a coccidiostat in the drinking water for 4 to 6 weeks, then watch the chickens carefully
in case a lot of blood appears in the droppings, that means the disease has started again.
20.2 Marek's disease
It is caused by a herpes virus that may result in death or severe production loss in both layer and meat
chickens. Vaccination will reduce the losses. It causes changes in nerves and tumours in the major
internal organs. It is shed from the feather follicles and spreads in fluff and dust, gaining entry when the
chicken breathes infected dust particles. Once present in a flock, it spreads rapidly to unvaccinated
poultry. Chickens between 10 and 24 weeks of age are the most susceptible. In the nervous form the
chickens are unable to stand, become paralysed, waste away from lack of food and water and may
become blind. In the visceral form grey-white tumours are found in the ovaries and other organs. The
chickens may show signs of depression, paralysis, loss of appetite, loss of weight, anaemia (pale
combs) dehydration (shrunken combs). Treatment is not effective. Diseased chickens should be
removed from the flock and destroyed. Protection is obtained by buying chickens vaccinated either at
day old or into 18-19 day old embryonated eggs (before hatching). Isolate vaccinated chicks during
their first two weeks of life so that their immunity will develop. Rear chicks separately so that they are
free from the infected fluff and dust of older birds. Make sure that you have a thorough clean out and
disinfection of sheds and equipment between batches of chicks using a disinfectant which is effective
against bacteria and viruses. Exposure of the sheds and runs to sunlight helps the disinfection process.
20.3 Chronic respiratory disease (CRD) (mycoplasmosis)
It occurs when chickens infected with Mycoplasma gallisepticum are stressed. The subsequent
invasion by secondary bacteria causes the major damage to the bird. Outbreaks occur at times of
stress, e.g. moving, chilling, vaccinating, beak trimming, worming, poor ventilation, damp litter and
ammonia build up or in the presence of other diseases. The disease is introduced by infected carrier
chickens or transport by persons who have handled CRD-infected birds. The chickens show sniffing,
rattling, sneezing, coughing and wet noses with retarded growth in growing chickens and a production
loss in hens, but deaths are few. Similar diseases are Coryza, Infectious bronchitis, and Fowl cholera.
Antibiotics will help control the disease and minimize secondary bacterial complications, but do not
control the disease completely. Suppliers of point of lay pullets can provide vaccinated pullets.
Mycoplasmosis, is caused by very small micro-organisms called mycoplasma. These are breathed out
into the air by diseased chickens and are breathed in by healthy chickens. Control this disease by
keeping very young chickens apart from older birds. Then the microbes cannot reach them. If the
chickens catch this disease, it will quickly go from one to the others. When the chickens have left this
house, you must clean out the house and leave it empty for two weeks before you put any more
chickens into it, This disease does not kill chickens very often, but it causes them to lay fewer eggs and
to grow slowly.
20.4 Lymphoid leucosis
It also causes tumours in organs, but does not cause paralysis. It is usually seen in chickens over 16
weeks of age and is a disease of the nervous system. It occurs more in older stock and growing pullets
than in young birds. There is no cure for Leucosis. A vaccine has been developed which will lower the
incidence of the disease. The chickens should be vaccinated by hatcheries at day old. The chickens
appear quite healthy but will have lost control and use of their legs. You can eat these chickens as the
meat is not affected. Chickens that get Leucosis will not recover and should be destroyed.
20.5 Fowl pox
It is spread by mosquitoes. It occurs mostly in chickens from 1 week to 10 weeks of age. The eyes,
beak and head will be covered with scabs. Most of the chickens will recover from the disease, but their
growth rate slows. Chickens bought from a hatchery should be vaccinated against fowl pox as
vaccination is the only cure. There is no drug treatment.
20.6 Vitamin deficiencies
These deficiencies rarely occur in chickens that are free ranged or fed a balanced ration. However, if the
feed is very old then some of the vitamins such as Vitamin A may be deficient. You can feed only fresh
bought feed, add 40 g /100 kg of feed of a vitamin supplement to the ration and allow the chickens to
free range for 1-2 hours per day or add fresh green feed to the chicken ration. Mineral deficiencies will
rarely occur in chickens that are free ranging and chickens that are fed a balanced ration. If calcium
deficiency in laying hens occurs, put crushed seashells or coral or limestone in a special feed box in the
corner of the chicken shed. Protein deficiencies are common if there are no natural high protein grain or
plants available. The deficiencies cause a very slow growth rate of young chickens and sometimes death.
In older birds, the breastbone is very pronounced and the chickens are very thin. Later the chicken
becomes very lazy and weak, walks with great difficulty and will die. Feed a high protein feed, such as
meat meal, or poultry concentrate with the sweet potato or other energy type feed being fed. Also, you
can boil some fish and mix with the other feeds. If soybeans, peanuts, mung beans and snake beans are
available, mix these grains with the other feed.
20.7 Botulism or food poisoning
It usually occurs more with ducks than chickens. It is caused by bacteria growing in stale wet feed that
has gone putrid. The chickens will sit down and extend their necks out as far as possible and will be
very drowsy. Death occurs in 1-4 days. If the chickens are fed outside, thoroughly clean out feed
troughs after every feeding. Change the site of feeding regularly, so that the ground under the feed
trough doesn't become saturated with feed. There is no cure.
20.8 Fatty liver of laying hens
It occurs only to chickens confined to laying cages. The chickens are confined to a small area and so
get very little exercise. High producing hybrid chickens are more prone to fatty liver than pure bred
stock, e.g. Rhode Island Red. There is very little that can be done for fatty liver as the first thing that the
farmer knows about it is the chicken has died.
21.0 Costs, returns and profits
See 6.9.20.0: Understanding the records
If people keep some village hens or modern hens so they can sell the eggs, then they must know how to
find out if they have made a profit. Students should be shown how to do this.
1. Costs
The two kinds of costs are establishment costs and production costs.
1.1 Establishment costs
These are costs you pay for things that will last for years. It would not be a good idea to take all these
costs away from the returns for one year. Instead you can make a guess at how many years these things
will last, say 5 years, and then divide the cost by 5 for working out one year's costs.
Establishment costs for egg project:
Costs of squared timber for cages $9.00
Cost of lock and key for door $1.10
Cost of oil drum for feeder $1.00
Total establishment costs = $11.10
1.2 Production costs
These are costs that you must pay each year. For example each year you must pay for some
Amprolium or other drug to stop coccidiosis.
Production costs for one year:
$9.40 for 500 grams of Sulfaquinoxiline drug (enough for 5 years) $1.80
Twelve hybrid layer chickens at 70 cents each $8.40
Freight costs $2.00
25 kg. of chicken starter feed at $14 per 50 kg. $7.00
Total production costs = $19.20
2. Returns
This is the money received when you sell eggs in a market. you must always keep a record of the returns
so you know how much money you have received.
Sold 27 dozen eggs at $1.10 per dozen = $29.70
3. Profit
1. Total establishment costs / 5 = $11.10 / 5 = $2.22
2. Total production costs = $19.20
Total costs = $21.42
Profit = (Returns - Total costs)
Profit for first year = ($29.70 - $21.42) = $8.28
Working out profit in this way may indicate:
1. Profits increase more hens are bought and more eggs are sold.
2. No profit is possible if less than 200 eggs are sold.
History
These teaching materials were originally written and illustrated by Mr J. A. Sutherland, Faculty of
Education, University of New England, Armidale, Australia and later edited by Dr J. Elfick, School of
Education, University of Queensland, Brisbane, Australia.