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CHAPTER 1

EXTERNAL BODY PARTS AND POINTS AND METHODS OF IDENTIFICATION IN POULTRY

The basic external parts of a chicken include the comb, beak, wattles, ears, earlobes, eyes, eye rings, wings, tail, thighs, hocks, shanks, spurs, claws, and toes. The differences between male and female include the size of the comb and wattles, the size of the spurs (in older birds), and the characteristics of the hackle and cape feathers. Hackle and cape feathers of males have pointed ends, whereas those of females have rounded ends. In addition, males have sickle feathers in their tails and hackle feathers on their backs, and females do not.

External body parts of a chicken

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Internal body parts of a chicken

1) Comb Comb is a small ice of meat above the chickens head. Various chickens have about 8 types of comb. In general we know about single comb, rose comb and pea comb. We can differentiate cock and hen by their comb. The comb of cock is slightly bigger

than hen comb.

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2) Nostril The nostril of chicken is near on the joint place of beak and comb.3) Beak Beak of chicken is on the front side of head. It is very strong and suitable to collect grains from the ground.

4) Eyes The chicken has two bright eyes. We can identify if they are healthy or not by their eyes. The eyeball is covered by the eye ring. When the eye is open, the eye ring appears as a ring of skin around the eye (thus the

name eye ring).5) Ear Chickens do not have external ears as humans do. The ears are just openings into the ear canal, and each is protected by a covering of

feathers.6) Ear Lobes The hanging skin from chicken ear is known as ear lobe. There are various colored ear lobe of chicken. We can see light red, deep red and white colored ear lobe of chicken. Chickens with white earlobes lay white eggs exclusively while birds with dark lobes lay

brown eggs. The fascinating Araucana breed of chickens can even have earlobes that are a pale green

or blue colour.7) Wattles The soft meat hanging from the two side of chicken beak is known as wattle. It is also of various colored.

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Dubbing is the procedure of removing the comb, wattles and sometimes earlobes of poultry. Removing the wattles is sometimes called "dewattling".

8) Wings The chicken has two wings. With those wings they can fly slightly. They have some feather in their wings which are suitable for flying. These feathers are

known as primary feather. They have about 10 primary feathers. We can’t see those if they do not spread their wings.

The axial feather separates the primary feathers and secondary feathers. When a hen molts, she starts losing feathers from the axial feather out.

9) Tail Both cock and hen has a tail. The feather of tail of cock gets curved to down when it become big sized and it looks like

a sickle. Hens are of different types. So, we can differentiate between hen and cock by their tail.

10) Main tail feathers The long straight feathers forming the tail, under the tail covers.

11) Saddle feathers Saddle feathers are the feathers in front of the tail. Both hens and roosters have saddles, but in a rooster the feathers are longer, softer, and

pointier.12) Sickle feathers

Sickles are the long, curling, showy feathers on the tail of a rooster.13) Vent

Eggs of chicken come out from the vent of chicken. Sperm also come out from the vent of chicken.

14) Leg The chicken has a pair of leg and every leg contain four small and a big size claw. The thigh of a chicken is the upper part of the leg attached to the body.

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The thigh ends at the lower leg (drumstick). The thigh is connected to the shank (foot) at the hock joint, which is equivalent of the

ankle in humans. Chickens stand and walk on their toes. Most chickens have three toes projecting forward

and one projecting back, sometimes referred to as the claw. A few breeds, however, have five toes on each foot. Some breeds also have feathers on their shanks and toes.

Leg of a cock Leg of a hen

METHODS OF IDENTIFICATION OF POULTRY

1) Toe Punching In order to keep up with certain bloodlines or strains we mark each of our

chickens soon after birth. When you have several different breeds or strains being born at the same time it can be quite easy to get them mixed up, especially if the strains resemble one another after they are older.

The web between the chick's toes are placed into the puncher hole side down, tooth side up. The puncher is then clamped firmly through the web.

They are easy to use and very inexpensive.

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2) Nose Marking Even more marking combinations can be added by nose marking (left nose, right

nose or both). The nostril covers of a chicken are clipped using this method with a small pair of scissors, fingernail clippers, or cuticle trimmers. We give nose mark soon after birth.

3) Leg Bands Leg bands are bracelet-like circlets, which can be attached to chicken’s leg to

keep them identifiable.There are several different kinds of leg bands:-Plastic leg bands

Most widely- used type of leg bands. These can become faded and fall off more easily than stronger leg band.

Metal leg bands These are almost indestructible. However, if chickens wear them in the snow or extremely cold temperatures, they can

freeze to the leg and cause frostbite. They may also rust if chicken walks in puddles or other sources of water.

Coil/spiral bands The least desirable type. They are shaped like a spring. They get very easily tangled and also fall off easily.

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Numbered zip ties They very easily fall off, and can become tangled on shrubbery or low branches- or even

the coop wire.

4) Wing Bands Wing bands are clipped through the wing of chicken at the shoulder using a wing banding

tool.

5) Neck Tags Neck tag is a quick attach tag that is very easy to read. Tag is ideal for universities or groups doing research on individual birds.

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QUESTIONS:

1. Explain the different identification methods used in poultry?

2. Mention the difference between hen and cock?

3. Explain the different types of comb in poultry.

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CHAPTER 2

VISIT TO INSTRUCTIONAL POULTRY FARM TO STUDY DAILY ROUTINE AND FARM RECORDS

Poultry Farm Records:

Keeping records in poultry farm is must for scientific care and management as well as for economic analysis of the farm. Records may be different for different types of poultry farming. The necessary information is to be recorded in a simple but scientific manner, either in the form of register or record sheet.

In brooder-cum-grower house, the most important information to be kept are number of day-old chicks and their hatch dates, daily mortality and culling, average weekly body weight and uniformity of stock, feed specification and daily feed intake, source of water and daily water intake, light on\off time, in-house maximum and minimum temperature, vaccination, medication, debeaking, transfer of pullet from grower house to layer house etc. In layer house, daily information is to be recorded is mortality and culls, feed consumption and egg production and other technical information including medication.

For calculation of cost of egg production in layer or breeder farming all expenditure and income must be recorded. The expenditure on various heads are to be kept as they occur like most of day old chicks or pullets up to point of lay, mortality, feed, labour, vaccine and other medicine consumables, maintenance cost, vehicle, depreciation of equipment and farm buildings, electricity and water, miscellaneous expenses like telephone, postage etc. The income on various heads is sale of eggs, sale of manure and gunny bags, sale of culls etc.

FOLLOWINGS ARE SOME EXAMPLE OF FORMAT USED FOR DIFFERENT OPERATIONS IN A POULTRY FARM:

Rearing Records for Broiler and PulletsStrain: Feed Source: Number received:Date Age Details Culled Balance

numberVaccination Weekly

weight

Monthly Laying Record SheetDate of transferring: Strain: Vaccination done: The flock in layer: Layer house no.: House:Date Death Culled Feed intake Eggs

collectedObservation

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Egg Collection and Disposal RegisterYear: Strain: Source: Month:Date Laying house

no.Egg collected Broken Disposal Balance

Mortality RegisterMonth: Year:SI no. Strain Sex Date of

deathCause ofdeath

PMreport no.

Bookvalue

Remarks

Feed RegisterMonth: Year:Date Opening

balance(kg)

Received(kg) Source Issued(kg) Closing balance(kg)

Composition of ration

Layer Farm Performance Record CardCard no.: Name of the farm: Date:Address:

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POULTRY FARMING ROUTINE MANAGEMENT PRACTICE FOR TODAY’S FARMER

Brooding techniques: Brooding techniques are those operational decisions you have to make in the first few

weeks of your chicken to give them the best start possible. They include decision on air quality, chick’s food and water quality and availability. Others include litter management, temperature and ventilation.

Daily feeding and watering After the brooding period comes the real business of raising the birds to maturity. Here again, food and water quality and availability, litter management, temperature and ventilation become important. Otherwise, the birds could be malnourished, sick and could die.

Daily record keeping Right from the first day of replacement or stocking your farm with new birds, record keeping begins. This record is necessary to keep the, feeding and watering, health records and financial records of the business.

Planned vaccination programme Vaccination programmes are always arranged according to specifications of Veterinary doctor. If you ignore this aspect of your poultry management, your birds may come down with flu. You know what that means.

Daily inspection for disease signs and isolation This is also very necessary. In poultry business, early disease detection is very important. Therefore, you have to watch your birds on daily basis for signs of diseases so as to be able to isolate them. Drug administration Drug administration is another area to watch. There must be a time chart for this which must be observed.

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Periodic litter disposal and change Wood shaving, watering and feeding cans are major debris to be gotten rid of

periodically. This should be among scheduled activities in the farm. Building and premises You have to know that the location, size and position of your farm matters to all we have said above. The farm building and premises (location) can ruin the entire business at once. So do well to make good plan for your farm location, size and maintenance.

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QUESTIONS:

1. What is the importance of farm record? Explain.

2. Mention the different records maintained in poultry farm (Layer as well as broiler).

3. Mention the poultry farming routine management practices for today’s farmers.

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CHAPTER 3

JUDGING AND CULLING OF POULTRYPoultry JudgingIn India, poultry judging refers to selection of birds on the basis of their physical appearances, breed characteristics and production performances; however, in other countries, like USA judging is also used for eggs, carcasses characteristics and further processed products.For purpose of judging, the bird may be divided into the following groups:1. Exhibition or show class.2. Utility or production class (layers or broilers).3. Exhibition cum game group.Objectives1. To develop healthy competition among breeders/owners and encourage them to develop superior quality birds based on the present day need.2. To exchange views and opinions among poultry farmers and extension workers.3. To become aware of the birds available and breeding programmes carried out elsewhere.Parts of birds for judging

Like other animals, the various parts of a chicken's body, including the feathers, have definite terms or names.

Different parts of feather

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Judging of Layer Judging of a good layer is based on certain extrinsic characters and related measurements

expected to indicate a laying bird. Accordingly, layers can be graded based on the following score card.Moulting Moulting is an annual physiological phenomenon of shedding of old feathers and replacing them with new feathers. In a good layer, moulting commences at and of the first laying season and completes the moult early. In a poor laver, it will commence early and is prolonged. There is a definite pattern; It starts from the head, passes on to neck, back and tail and then the primary and secondary feathers.Pigmentation Pigmentation is also a good indication of reproductive status of a layer, but can be depended upon only in a bird with yellow skin and the feed also has adequate carotenoid pigments.Judging broilers for meat production Broilers are young immature chicken of either sex usually below 5 to 6 weeks of age, tender mated with smooth textured skin and a soft pliable breast bone cartilage.

ScorecardParameters PointsHealth and vigour of bird 5

Body conformation and abdominal capacity 25

Moulting and plumage 15

Pigmentation 10

Condition of head, wattle, vent and others 25

General Appearance - Bird should have a compact body, broad and fleshy comb should be medium in size with bright and prominent eyes. Birds should be free from common defects such as breast blisters, crooked keel, split wing, coarse beak, injuries etc. Skin should be smooth and pliable.

Health and Vigour - Birds should be apparently healthy and free from any signs of disease like unthriftiness, pale or cyanotic comb etc. Excessive fat is undesirable.

Breast wide and heavily fleshed, keel bone should be straight, long and parallel to the back. May have very slight curve but should not be crooked. Breast can be measured in terms of breast angle and by measuring the girth.

Back and Rib - Back should be broad and long from front to tail, ribs wide enough. Legs and Thigh - Bird should have normal legs of moderate length and well fleshed. Long and

thin legs are undesirable, while thick plumpy legs are preferred. Feathering - Should be closely feathered spreading uniformly on the body. It may have small

area of scattered pin feather which when present should be long enough for easy removal upon processing. Bare back grades down the broilers.

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Preparation of Poultry for Show A. Selection of birds Select only healthy birds since only such birds will have good physical condition and bright appearance for which the chances for good price.B. Training of birds It is very necessary that the bird shows its best worth to the judges and do not get excited in the pen when visited. Select the bird at least one week before the show, Handle each bird two to three times a day in a manner similar to that used during judging so that the birds get trained and do not get excited during the show.C. Washing the birds Washing may be necessary in white birds arranged for the show. The birds are washed with detergent solution. If external parasites are present, birds may be dipped in certain mild pesticide. A bird can be washed 15 to 20 minutes and the bird should be placed in a drying cage and it gets dried in 12 to 18 hours. The birds should be dried slowly for best results.D. After washing A small piece of cloth is moistened with baby oil or vitamin E and is rubbed over the comb, wattles, beak and shank of the bird. A mixture of equal parts of alcohol, glycerine and olive oil makes an excellent cleaning and polishing solution for shank, feet, comb and wattles. The nails and beak may be trimmed if necessary.

E. Transporting the birds Transport the birds in a clean cage with straw or wood shavings as bedding material. Do not provide water since it will spill and spoil the bedding material. If the birds are to be transported to a long distance, water should be provided at intervals during transport.F. Care of birds during show Make sure that the birds are provided with plenty of food and water during the show.G. Care of birds after the show After the show, the birds should be quarantined and should not be mixed with other birds in the farm immediately because it may transmit some diseases which has been acquired during the show from other birds. After 14 days of quarantine, they can be mixed with other farm birds.Culling among layers - Culling is an important managemental procedure to be practiced in case of layers and breeder females. It is a continuous operation once laying starts because all the layers/breeders, despite of good start may not be persistent in laying for complete laying period. Therefore, usually monthly culling is followed to improve economy by removing unproductive birds. Most of the characters in judging pertaining to productive features are evaluated during culling. If the productive characteristics are up to the standards, then general defects counted in judging are not given any weightage for culling. The characters that distinguish poor layers are given below.

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CULLING OF POULTRY

Definition:Removal of uneconomical birds and non producers from the flock is called culling. ORElimination of such birds which lack the qualities for which they were bred, whether egg production or meat purpose.Objectives:1. To remove unproductive, uneconomic/unprofitable birds from flocks.2. To improve performance of flock.3. To increase or maintain good efficiency of the flock.4. To reduce cost of maintenance of flock.5. To increase the profit from the flock by selecting good layers.Importance: Poultry farmer may start with a good stock but invariably there will be some birds which do not grow well or hens which do not lay well. Such birds reduce the efficiency of the flock and also increase the maintenance cost of flock because they require same attention as normal growing bird or good laying hens. Therefore culling is very important and should be a continuous process on every farm whether small or large, throughout the year.

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Equipments Used For Culling1. A catching hook2. A catching crate3. A wire panel for keeping chickens in the corner4. A scale for weighing.5. A wooden panel for keeping chickens in cornerParameters for Culling1. Poor growth/stunted2. Poor feathering3. Lack of vigour4. Poor body shape and fleshing5. Low egg production: (a) Non layers (b) Inferior layers6. Layers above 19 months of age7. Delayed maturity8. Defective body parts in hens.Culling of Growing Birds/Pullets Chicken with poor body shape, fleshing capacity, long legged, underdeveloped, narrow bodied, diseased, crooked breast bone, untrue to the type, defective tail carriage, having grey/pearly eyes, plumage lacking luster, droopy feathers and dull looking must be culled. The growing stock must be culled out as early as possible to save labour, feed cost, space and avoid contamination of certain diseases to other birds in the flock.Culling of Non-Layers, Poor Layers and Old Hens The profits from a laying flock are directly related to egg production. Since the cost of feed accounts to nearly 80% of the total cost of egg production, it is advisable to cull poor layers and non laying hens and hens over 19 months age.

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Effect of Culling on Egg Production By culling poor layer the total numbers of eggs produced by the flock would be less. This is because some birds that are culled would have produced some eggs if they were in flock. By judicious culling the farmer will be able to save cost of feed, labour and maintenance thereby increase the efficiency of flock and profit to be obtained from all the hens in flock per egg. Record of daily egg production can be used for convenience to keep information on number of eggs produced each day and the number of mortality of birds.

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QUESTIONS:

1. What are the objectives of culling of poultry in a flock?

2. Define culling? Mention the different criteria for culling of poultry?

3. How you will prepare your birds for show purpose?

4. Write the differences between good layer and poor layer?

5. What are the different physical characteristics of a bird which indicates it’s laying ability?

6. How will you judge a layer bird?

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CHAPTER 4

PLANNING AND LAYOUT OF HOUSING FOR DIFFERENT CLASSES OF POULTRY

Planning and Layout of Housing for Different Kinds of Poultry Planning a Poultry Farm:Before planning to start a poultry farm, one must consider the following factors for trouble free long operation:(1) Selection of the site(2) Orientation of houses(3) Layout of operations(4) Design and constructionSelection of Location

Poultry house should be located away from residential and industrial area. It should have proper road facilities. It should have the basic amenities like water and electricity. Availability of farm labours at relatively cheaper wages. Poultry house should be located in an elevated area and there should not be any water-

logging. It should have proper ventilation.

Layout of poultry farmA small size poultry farm doesn’t require any special layout as it involves construction of

only one house. The medium and large size farms require special considerations for placement of building in the farm premises. The basic principles to be observed for layout are

Layout should not allow visitors or outside vehicles near the birds.

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The sheds should be so located that the fresh air first passes through the brooder shed, followed by grower and layer sheds. This prevents the spread of diseases from layer houses to brooder house.

There should be a minimum distance of 50-100 feet between chick and grower shed and the distance between grower and layer sheds should be of minimum 100 feet.

The egg store room, office room and the feed store room should be located near entrance to minimize the movement of people around the poultry sheds.

The disposal pit and sick room should be constructed only at the extreme end of the site.Different Types of Poultry Houses:-

Brooder/Chick house-It is used to brood and rear egg-type chicks from 0 to 8 weeks of age.

Grower house-It is used to grow egg-type birds from 9 to 18 weeks of age. Brooders cum Grower house-Here, the birds are reared from 0 to 18 weeks of age

(entire brooding and growing period of egg-type chicken). Layer house-In which birds over 18 weeks of age are reared, usually up to 72 weeks of

age. Broiler house-In which broilers are reared up to 6 weeks of age. Breeder house-In which both male and female breeders are maintained at appropriate

sex ratio. Environmentally controlled (EC) house-In which entire environment is manipulated in

such a way that is optimum for the bird’s growth.Optimal Environmental Conditions for Rearing Broilers:-Temperature - 22-30oC (70-85oF) Relative Humidity - 30-60%Ammonia level - Less than 25 ppm Litter moisture - 15-25%Air flow - 10-30 meters/minute House Orientation (Direction)

The poultry house should be located in such a way that long axis is in east-west direction. This will prevent the direct sunshine over the birds. Size

Each broiler require one square feet of floor space while a layer requires two square feet of floor space under deep-litter system of rearing. So the size of the house depends on the number of birds to be reared. Length

The length of the house can be of any extent. The number of birds reared and availability of the land determines the length of poultry house. Width

The open sided poultry houses in tropical countries should have a width not more than 22 to 25 feet in order to allow ample ventilation and aeration at the mid-portion. Sheds wider than

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this will not provide adequate ventilation during the hot weather. If the width of the shed is more than 25 feet, ridge ventilation at the middle line of the roof top with proper overhang is a must. Hot air and obnoxious gases which are lighter than air move upward and escape through ridge ventilation. Height

The height of the sides from foundation to the roof line should be 6 to 7 feet and at the centre 10 to 12 feet. In case of cage houses, the height is decided by the type of cage arrangements (3 tiers or 4 tiers).

FoundationGood foundation is essential to prevent seepage of water into the poultry sheds. The

foundation of the house should be of concrete with 1 to 1.5 feet below the surface and 1 to 1.5 feet above the ground level.

FloorThe floor should be made of concrete with rat proof device and free from dampness. The

floor of the house should be extended 1.5 feet outside the wall on all sides to prevent rat and snake problems. Doors

The door must be open outside in case of deep-litter poultry houses. The size of door is preferably 6 x 2.5 feet. At the entry, a foot bath should be constructed to fill with a disinfectant.

Side wallsThe side wall should be of 1-1.5 feet height, and generally at the level of bird’s back

height. This side wall protects the bird during rainy days or chill climate and also provides sufficient ventilation. In case of cage houses, no side wall is needed.

RoofThe roof of the poultry house may be thatched, tiled, asbestos or concrete one depending

upon the cost involvement. Different types of roofs are Shed, Gable, Half-monitor, Full-monitor (Monitor), Flat concrete, Gambrel, Gothic etc. Gable type is mostly preferred in tropical countries like India.

Overhang

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The overhang of the roof should not be less than 3.5 feet in order to prevent the entry of rain water into the shed.

LightingLight should be provided at 7-8 feet above the ground level and must be hanged from

ceiling. If incandescent bulbs are used, the distance between two bulbs is 10 feet. In case of fluorescent lights (tube lights) the distance is 15 feet.

Systems of Poultry HousingPoultry can be housed under different systems based on following factors:

1. Availability of land2. Cost of land3. Type of farming activity4. Climatic condition5. Labour availability

Broadly, poultry housing systems are classified into three systems:1. Free Range or Extensive System2. Semi-Intensive System3. Intensive System

1. Deep-litter system2. Slatted floor system3. Slat cum litter system4. Cage system

1) Free Range SystemThis system is adopted only when adequate land is available to ensure desired stocking

density by avoiding overcrowding. We can rear about 250 adult birds per hectare. A range provides shelter, greens, feed, water and shade. Foraging is the major source of feeding for birds. Shelter is usually provided by temporary roofing supported by ordinary poles. The fields are generally used on rotational basis after harvesting of crops by moving birds from one field to another depending on cropping programme. All categories of birds can be reared in this system.

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This system is most preferred for organic egg production.

Advantages Less capital investment Cost of housing is least Feed requirements are less since birds can consume fairly good amount of feed from

grass land. Fertility of soil can be maintained.

Disadvantages The scientific management practices can not be adopted. Eggs are lost when laid inside the dense grasses unless special nests are provided. Losses due to predatory animals are more. Wild birds may bring diseases unless proper care is taken.

2) Semi-Intensive SystemAs the name indicates birds are half-way reared in houses and half-way on ground or

range, i.e. birds are confined to houses in night or as per need and they are also given access to runs. The houses are with solid floors while runs are fields only. The success of rearing depends on maintenance of condition of runs to reduce the contamination. Runs can also be used on turn basis. The stocking density rate on an average for adult birds is 750 per hectare. This system is usually adopted for duck rearing. The feeding and watering facilities are provided in the pen.Advantages

More economical use of land compared to free range system Protection of birds from extreme climatic conditions Control over scientific operation to some extent possible

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Disadvantages High cost for fencing Need for routine cleaning and removal of litter material from the pen

3) Intensive SystemBirds are totally confined to houses either on ground/floor or on wire-netting floor in

cages or on slats. It is the most efficient, convenient and economical system for modern poultry production with huge numbers.Advantages

Minimum land is required for farming. Farms can be located near market area. Day-to-day management is easier. The production performance is higher as more energy is saved due to restricted

movements. Scientific management practices like breeding, feeding, medication, culling etc. can be

applied easily and accurately. The sick birds can be detected, isolated and treated easily.

Disadvantages Bird’s welfare is affected. They cannot perform the natural behaviour like roosting,

spreading wings, scratching the floor with legs etc. Since they are not exposed to outside sunlight and feed sources, all the nutrients should

be provided in balanced manner to avoid nutritionally deficient diseases. Chances for spreading of diseases are more.

Deep Litter SystemIn this system the birds are kept inside the house all the time. Arrangement for feed,

water and nest are made inside the house. The birds are kept on suitable litter material of about 3” to 5” depth. The word litter is used for fresh litter material spread on the floor. Usually paddy

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husk, saw dust, ground nut hulls, chopped paddy straw or wood shavings are used as litter materials. This arrangement saves labour involved in frequent cleaning of faecal matter (droppings), however it needs periodical stirring. The litter is spread on the floor in layers of 2” height every fortnightly till the required is achieved.

Advantages

Vitamin B2 and Vitamin B12 are made available to birds from the litter material by the bacterial action.

The welfare of birds is maintained to some extent. The deep litter manure is a useful fertilizer. Lesser nuisance from flies when compared to cage system.

Disadvantages Because of the direct contact between bird and litter, bacterial and parasitic disease may

be a problem. Respiratory problems may emerge due to dust from the litter. The cost of litter is an additional expenditure on production cost. Faults in ventilation can have more serious consequences than in the cage system.

The built up litterDeep litter or built up litter is accumulation and decomposition of litter material and

excreta until it reaches a depth of 8” to 12”, after an original start of 3” to 5” depth. Bacterial action decomposes litter and excreta into crumble form and heat is produced during decomposition which keeps litter dry and warm. If the amount of droppings exceeds the litter, fresh litter will be added to lower the amount of droppings. Periodical stirring of the litter should be carried out for an effective functioning of built-up litter. After one year, the litter is changed and the decomposed litter is used as good quality manure. The best built-up litter should be dry, friable and free from obnoxious odour.Slatted (Slotted) Floor System

In a slatted floor, iron rods or wood reapers are used as floor, usually 2-3 feet above the ground level to facilitate fall of droppings through slats. Wooden reapers or iron rods of 2” diameter can be used on lengthwise of the house with interspaces of 1” between rods.

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Advantages Less floor space per bird is needed when compared to solid floor system. Bedding is eliminated Manure handling is avoided Increased sanitation Saving in labour Soil borne infection is controlled

Disadvantages Higher initial cost than conventional solid floors Less flexibility in the use of the buildings Any spilled feed is lost through the slots More fly problem

Slat (Slot) Cum Litter SystemThis system is commonly practiced for rearing birds for hatching eggs production,

particularly meat-type breeders. Here, a part of the floor area is covered with slats. Usually, 60% of the floor area is covered with slats and rest with litter. Feeders and waterers are arranged in both slat and litter area. In case of breeder flock, nest boxes are usually kept on litter area.Advantages

More eggs can be produced per unit of floor space than all solid floors. Fertility is better with the slat cum litter house than with the all-slat house.

Disadvantages Housing investment is higher with the slat cum litter house than with the all-litter house. The separation of birds from the manure beneath the slats commonly results in fly

problems.Cage System

This system involves rearing of poultry on raised wire netting floor in smaller compartments, called cages, either fitted with stands on floor of house or hanged from the roof. It has been proved very efficient for laying operations, right from day-old to till disposal. At present, 75% of commercial layers in the world are kept in cages. Feeders and waterers are attached to cages from outside except nipple waterers, for which pipeline is installed through or above cages. Auto-operated feeding trolleys and egg collection belts can also be used in this rearing system. The droppings are either collected in trays underneath cages or on belts or on the floor or deep pit under cages, depending on type of cages.

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Advantages Minimum floor space is needed More number of eggs per hen can be received Less feed wastage Better feed efficiency Protection from internal parasites and soil borne illnesses Sick and unproductive birds can be easily identified and eliminated Clean eggs production Vices like egg eating, pecking is minimal Broodiness is minimal No need of litter material Artificial Insemination (AI) can be adopted

Disadvantages High initial investment cost. Handling of manure may be problem. Generally, flies become a greater nuisance. The incidence of blood spots in egg is more. Problem of cage layer fatigue. (It is a condition, in which laying birds in cages develop

lameness. It may be due to Ca and P deficiency but the exact reason is not known). In case of broilers, incidence of breast blisters is more, especially when the broilers

weight is more than 1.5 kg.Types of CagesBased on the number of birds in a cage, it is classified as

Single or individual bird cage (only one bird in a cage). Multiple bird cages (from 2 to 10 birds, usually 3 or 4 birds per cage). Colony cages (holding birds more than 11 per cage).

Based on the number of rows Single-deck Double-deck Triple-deck Four-deck Flat-deck

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Based on arrangement of cages1) Stair-step cages

a) M-type cagesb) L-type cages

2) Battery cages (Vertical cages)

Based on the type of bird reared1. Brooder/Chick cages2. Grower cages3. Layer cages4. Breeder cages

Broiler Cage:1) Brooder cage/Chick cage

Brooder cage

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Specifications: Front feeding length : 60 inchFront and back height : 12 inch Depth : 36 inch

No. of chicks (0-8 weeks) accommodated per box : 60 Chick cages are arranged either as single deck or double deck system. The feeders and

waterers are arranged on outside. Now-a-days nipple drinker system is followed from day-old itself. Newspaper may be spread over the cage floor for first 7 or 10 days. Feed is usually provided inside the cage during the first week of age.2) Grower Cage:

Grower cage Grower cageSpecifications: Front feeding length : 30 inch

Front and back height : 15 inch Depth : 18 inch

No. of growers (9 to 18 weeks) accommodated per box : 10

3) Layer C:ageTwo types of stair-step layer cages are commonly used in open-sided poultry houses

1. Conventional cages2. Reverse cages (Californian cages)

a) Conventional cages

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Specifications for each box:

Front feeding length : 15 inchFront height : 18 inchBack height : 15 inchDepth : 18 inch

b) Reverse cagesSpecifications for each box: Front feeding length : 18 inch

Front height : 18 inch Back height : 15 inch Depth : 15 inch

These cages can hold 3 to 4 birds. They are arranged either in 2-tier or 3-tier. A slope of 1/6 is provided in conventional cages, where as in reverse cages the slope is 1/5.Advantages of reverse cages over conventional cages

1. More feeding space is available in reverse cages. So, all 4 birds can take feed at a time, where as in conventional cages, 3 birds can take feed and the other one is waiting at the back.

2. Number of cracked eggs is less due to lesser rolling distance.3. Better ventilation in reverse cages than conventional cages.

Elevated Cage Layer HouseThe height of the shed is raised by 6-7 feet using concrete pillars. The distance between

two pillars is 10 feet. Two feet wide concrete platforms are made over the pillars. When 3 ‘M’ type cages are arranged 4 platforms are needed. In case of 2 ‘M’ and 2 ‘L’ type cages are arranged 3 platforms are needed. When constructing platforms projecting angles or iron rods to be provided to fix the cages. The inter-platform distance is 6-7 feet depending upon the type of the cages used. The total height of the house is 20-25 feet and the width is 30-33 feet. This type of houses provides sufficient ventilation in tropical countries.

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Floor space requirements

TypeAge

(in weeks)Deep-litter

(Sq.ft)Cages(Sq. ft)

Egg-type chicken0-8 0.60 0.209-18 1.25 0.30>18 1.50 0.50

Meat-type chicken0-4 0.30 -4-8 0.75 -

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QUESTIONS:

1. Write the different criteria for selection of site for the poultry farm?

2. Explain the different housing system for poultry (Layer and broiler) in detail.

3. Give the floor space requirements for different classes of poultry?

4. Mention the advantages and disadvantages of deep litter system and cage system of

housing respectively.

5. Give the optimal environmental conditions for rearing of broiler and layer birds,

respectively.

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CHAPTER 5

FEED FORMULATIONS, PREPARATION AND MIXING PROCEDURE OF POULTRY FEED

Feed FormulationDefinition:

Feed formulation: Feed formulation is the process of quantifying the amounts of feed ingredients that need to be combined to form a single uniform mixture (diet) for poultry that supplies all of their nutrient requirements.

1. Nutritional requirements: BIS, NRC, ARC.2. Availability of feed ingredients-Locally and easily available.3. Non nutrient characteristic of feeds: Free of anti-nutritional factors.4. Inclusion level of feed ingredients:

Feed Formulation for Poultry:While formulating feed it should be kept in mind that a balanced feed should contain

desired levels of energy, protein, crude fibre, moisture, vitamins, minerals, amino acids, fatty acids, non-nutrient feed additives and performance enhancers to help the birds to perform as per their genetic potentiality. The following information are essentially required for formulation of poultry feed.1. Chemical composition of feed ingredients

Composition of feed stuffs may vary due to various factors like varietal variation of crop, soil type and environmental conditions in which the crops are grown, methods of estimation, etc.

2. Nutrient requirements of poultryFortunately, the nutrient requirements of chicken are known in much detail and

accurately than other farm animals. Several standards are available like NRC (National Research Council, 1994), ARC (Agricultural Research Council, 1975), BIS (Bureau of Indian Standards, 1992), etc. Nutrient requirements may vary due to types of bird (broiler or layer or breeder), and their ages. For commercial layer chicken, three types of feed are commonly used, viz. chick feed (0-8 weeks), grower feed (9-20 weeks) and layer feed (21- 72 weeks or during the laying period); and for commercial broiler chicken, two types of feed are commonly used, viz. broiler starter (0-4 weeks) and broiler finisher (5-6 weeks). Environmental conditions, system of housing (environmentally controlled house or open house), productivity level of birds, and stress factors are also to be considered in regard to nutrient requirements of birds.

3. Rate of inclusion of feed ingredients4. Cost, quality and availability of feed ingredients is about 70% of the total expenditure of

poultry farming due to feed. So the cost of feed ingredients should be considered while

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preparing feed for poultry. If the feed ingredients are procured from the locality, the cost may be somewhat less. However, the quality of the feed should not be compromised. The feed ingredients should be fresh and free from fungal contamination. Sometimes feed ingredients are adulterated, e.g. fish meal may be adulterated with urea, soybean meal is adulterated with rice bran, etc. So quality evaluation of feed ingredients is an important task in this regard. For this assistance of feed analytical laboratories may be sought.5. Method of Feed Formulation: The feed formulation can be done by hand calculation method or with the help of computer.a. Feed formulation by hand calculation: It is also called trial and error method. It requires a lot of time and labor, and only a few "ingredients" can be considered for formulation of compounded feed. However, for formulating simple feed by considering major nutrients (like ME, CP, Ca and P) this method may be adopted.The steps are follows:1. Fix certain levels of nutrients as per a specific category of requirements of feed (like broiler

starter or broiler finisher, etc.) .The feed ingredients are added to provide nutrients per kg or per 100 kg or per 1,000 kg compounded feed basis.

2. Keep space for minor ingredients as such minor ingredients are feed additives and supplements like: vitamins, trace minerals, liver tonics, anticoccidial drugs, antibiotic growth promoters, etc. They can be added in the following quantities. broiler starter feed (per 100 kg) -trace mineral premix 100g, vitamin premix 25g, anticoccidial premix 50g, antibiotic growth promoter premix 50g, liver tonic 25-50 g, toxin binder 200g, choline chloride 100g and enzymes 50g, respectively.

3. Keep space for synthetic amino acids like lysine and methionine. However, the cost of such ingredients should be kept in mind after calculating the level of amino acids contributed by protein sources, especially animal proteins and soybean (rich in lysine).

4. Keep space for common salt (NaCI). The salt content is not usually calculated, and 0.5 to 1.0 % salt is generally added to the feed.

5. Keep space for calcium and phosphorus. The feed of the phosphorus content should be calculated in terms of the available phosphorus. Limestone supplies calcium and bone meal supplies phosphorus.

6. Fix the level of animal proteins, these are usually added at a fixed level because of the cost, and these ingredients supply the limiting amino acids (lysine and methionine) at higher levels than other feed ingredients.

7. Fix the level of cereal by-products like rice bran, etc. It may be fixed up to 10% level.8. Calculate the nutrients from the above feed ingredients. Then subtract these values from the

required values of nutrients for a specific category of chicken like broiler starter or broiler finisher, etc. The different nutrients (especially ME and CP) need to be supplied from major feed ingredients like cereals and oil cakes. This can be done by trial and error method or Pearson's square method.

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9. Finally calculate the ME, CP, lysine, methionine, calcium and phosphorus. At this stage, the ME and CP contents of the feed should be as per the recommended requirements.

10. If there is any gap between calculated and recommended values of calcium and phosphorus that can be added to the dicalcium phosphate or rock phosphate in the case of phosphorus, and by adding shell grit, marble chips or calcite powder, etc. in case of calcium. The differences in amino acids, if any, can be met by adding synthetic sources.

11. Now adjust the total amount of feed by adding cereals or cereals to the products to make it 100%.

b. Feed Formulation with the Help of Computer Many software packages are available. They are Excel based or Visual Basics. Least cost

feed with several feed ingredients can be easily formulated with the help of computer. This method considers price variation and nutrient composition of feed ingredients as well as nutrient requirements of various categories of birds. In this method, feed formulation can be done at the fastest possible time with a high degree of precision.

Make feed is a comprehensive feed formulation software, designed to combine expertise, knowledge and standards of recent technologies in the field of poultry nutrition. It provides integrated and efficient solution for balanced formulation of rations for various categories of poultry, which will help immensely to poultry farmers.

MethodS of Poultry Feed Formulation:1 .By trial and error method:-Feed ingredients are interchanged by trial and Error until right combination is reached.-The most practical method

2 .Person square method:- This is simple, easy and direct method.- Only one or two nutrients can be balanced at a time.

3 .Algebric equations4 .By using computer/least cost formulation/linear programming

Composition of Broiler RationIngredients Starter (0-5 week)% Finisher (6-7 weeks)%

Yellow maize 47.00 54.50Rice polish 8.00 10.00Soybean meal 17.50 14.00Groundnut cake 15.00 11.00Unsalted dried fish 10.00 8.00Mineral mixture 2.00 2.000Salt 0.50 0.5Total 100 100

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Composition of Grower Ration Ration of Layer Mash

Ingredients Percentage Ingredient PercentageYellow maize 43 Yellow maize 47Soybean cake 8 Soybean meal 12Gingelly oil cake 5 Gingelly oil cake 4Fish Meal/dried salted fish 6 Groundnut oil cake 6Rice polish 16 Rice polish 13Wheat Bran 20 Wheat Bran 4Salt 0.25 Fish meal 6Mineral mixture 1.75 Dicalcium phosphate 1Total 100 Salt 0.25

Mineral mixture 1.75Shell meal 5Total 100

Maximum Inclusion Level of Feeds in Poultry Ration

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Nutrients Requirements For Chicken on DM Basis ( BIS 1992)

Characteristics Chick (0-8 week ) Grower Layer Breeder

Moisture % (maximum) 11 11 11 11CP % (minimum) 20 16 18 18CF% (maximum) 7 8 8 8Acid Insoluble Ash % (max) 4 4 4 4Salt * (NaCl) % (max) 0.6 0.6 0.6 0.6Calcites % 1.0 1.0 3.0 3.0Phosphorus % (available) 0.5 0.5 0.5 0.5Lysine % 0.9 0.6 0.65 0.65Methionine % 0.3 0J5 0.3 0.30Methionine + Cystine (%) 0.6 0.5 0.55 0.55ME (Kcal/kg) 2600 2500 2600 2600Calorie-Protein ratio 130 156 144 140

Feed Preparation: Types of Feed Preparation;

1) Mash2) Pallets3) Crumbles

Less wastage when using pallets or crumbles Poultry grow faster.

MASH CRUMBLES PELLETS

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MashTo put it simply mash is a loose and unprocessed version of chicken feed. Similar to the texture of potting soil, mash is the finest variety of chicken feed commonly available. Mash is normally used for baby chickens, as it is easy to digest, however it is not uncommon for fully mature chooks to be fed mash. The main issue with mash varieties of chicken feed is that its texture often results in an increase of incidental waste, so bare that in mind.

CrumbleIn simple terms crumble is a coarse variety of mash but not as compact of pellets. Reminiscent of the texture of oatmeal, crumble is a semi-loose variety of chicken feed that is slightly easier to manage than mash. Some chicken lovers use crumble to bridge the gap between mash and pellets for their flock. Others claim that their girls just simply prefer the crumbly texture. Whatever your reasons for using crumble instead of mash or pellets at the end of the day it shouldn’t make any significant difference to your flock’s health.

PelletsPellets are perhaps the most common variety of chicken feed available. Just like it sounds pellets are essentially little compact cylinders of chicken feed goodness. One of the benefits of using pellets is that they hold their shape nicely, which means they won’t go to waste if your ladies accidentally knock their feeder over. Easy to manage, store and serve, pellets often become the first choice for most backyard chicken keepers.

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QUESTIONS:

1. Mention the difference between crumbled, mash and pelleted feeds?

2. Write the nutrient requirements for different classes of poultry?

3. Mention the different criteria required for formulation of poultry feed.

4. What are the different methods for poultry feed formulation?

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CHAPTER 6

HATCHERY OPERATIONS, INCUBATION AND HATCHING EQUIPMENTS

Hatchery Operations: The operation of a chick hatchery involves the production of the largest number of quality chicks possible from the hatching eggs received at the hatchery. In addition, chicks must be produced economically.The sequences of hatchery operations followed in commercial hatcheries are:

Securing hatching eggs Traying hatching eggs Fumigation Cold storage Warm eggs prior to setting Loading of eggs Candling Transfer of eggs Pulling the hatch Hardening Grading Sexing Vaccination Chick delivery Washing and cleaning Disposal of waste

1) Securing hatching eggsHatcheries can get the hatching eggs from any one of the following ways:

From own breeder flock From other breeder flocks From other hatcheries

2) Traying hatched eggs The eggs from the breeder flocks should be transferred to the egg setter trays in the hatchery

immediately after receiving.

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2) Fumigation of hatching eggsAfter traying, eggs are to be kept in the fumigation chamber for fumigation. Fumigating

with 3x concentration of formaldehyde for 20 minutes will kill about 97.5 to 99.5% of the organisms on the shells. One ‘x’ concentration means 20 g of KMnO4 with 40 ml of formalin for 100 cubic feet (3x means 60 g of KmnO4 + 120 ml of formalin for 100 cubic feet).

4) Cold StorageWhen the eggs are not set immediately after receiving, they should be kept in cold room

at the temperature of 650C of and 75% relative humidity.5) Warm eggs prior to setting

Approximately 6 hours prior to placing eggs in the setter they should be moved from the egg-cooler room to normal room temperature. Here, atmospheric air condenses over egg shell and form water droplets over egg shell, which is called as ‘Sweating’. It is advantageous to warm eggs before placing them in the incubator by avoiding creation of low temperature in the machine by placing cool eggs directly.6) Loading of eggs

Placing of eggs in the setter is called ‘Loading of eggs’. Eggs can be set in the setter either all-in all-out basis or batch basis. Most of the commercial hatcheries are practicing batch system of loading eggs in the setter that will minimize the initial time taken to reach normal incubation temperature in the setter. In this case, each setter is having hatching eggs with different stages of embryonic developments.7) Candling

Candling is a process in which eggs are kept in front of a light source to find out the defects in egg shell, embryonic development etc. Candling can be done as early as five days of incubation, but errors in candling often occur at this time. Under commercial operations,

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candling is done when the eggs are transferred from setter to hatcher (at 19th day for chicken eggs). There are two methods of candling that can be used. The fastest method involves the use of a table or mass candler. An entire tray of hatching eggs may be placed on the mass candler and examined with one observation. Candling with a spot candler or individual candler is a little slower, but it is more accurate.8) Transfer of eggs

In modern incubators, eggs are transferred from setter to hatcher at 19th day of incubation (for chicken egg) or when approximately 1% of the eggs are slightly pipped. In general, one-seventh of total incubation period is needed to keep eggs in the hatcher.9) Pulling the hatch

The process of removing the chicks from the hatcher is often called pulling the hatch. Chicks should be removed from the hatcher as soon as all are hatched and about 95% are dry. Excessive drying in the hatcher should be avoided.10) Hardening the chicks

When the chicks are first placed in the chick boxes they are soft in the abdomen, are not completely fluffed out, and do not stand well. They must be “hardened” by leaving them in the boxes for 4 to 5 hours. Such hardening makes it easier to grade the chicks for quality, and the chicks are more easily vent-sexed.11) Grading the chicks

No chick below the minimum standard should be allowed to go to a customer. Some standards for quality are, 1) No chick deformities, 2) No unhealed navels, 3) Above a minimum weight, 4) Not dehydrated and 5) Stand up well.12) Sexing the chicks

Layer type day-old chicks are needed to be sexed separated either by vent sexing or auto- sexing (feather sexing). In case of meat-type day-old chicks sexing is not practiced.

13) VaccinationMost chicks are vaccinated against Marek’s disease in hatchery before delivery. Most

common method of vaccination of day-old chicks is by subcutaneous method in the neck.

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14) Chick deliveryBaby chicks should reach the customer’s farm early in the morning. Not only the

weather is cooler during this part of the day but the early arrival allows a full day for close observation of the chicks by the caretaker.15) Washing and cleaning

Cleaning the hatchery between hatches is of primary importance. The process must be complete. Except for the setters and setter room, every piece of equipment must be thoroughly vacuumed, scrubbed, disinfected and fumigated.16) Disposal of wastes

Hatchery wastes includes infertile and non-hatched eggs and dead and cull chicks that should be disposed in such a manner not to create problem to the neighbour’s and also not to contaminate the hatchery premises.

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Steps Involved in Commercial Hatchery Operations

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IncubationThe process of applying heat, either naturally or artificially, to eggs to cause them to hatch.

Methods of Incubation:There are two methods of incubation:(1) Natural method - In this method eggs are incubated with the help of broody hens(2) Artificial method - Eggs are incubated in "egg incubators"

Natural Method of Incubation:-It is still popular with small poultry keepers in remote rural areas in many tropical

countries. Although this method is fast disappearing and being replaced by artificial method, still it may be worthwhile to consider the following points regarding the natural method of incubation.

Broody hens – A broody hen used for incubating eggs should be healthy, quiet, a good sitter and have good body size. She may be tested with the help of dummy eggs for her interest to sit on eggs. She should be treated for internal and external parasites before allowing her to sit on eggs.

Nests – A saucer shaped nest made of bamboo basket or wooden box filled with bedding materials like clean cut grasses or chopped straws should be provided at safe and comfortable place.

Management of broody hens – Depending upon the size of hen 10-15 eggs can be placed under one bird. The broody hen should be taken out at least twice a day for about 30 minutes to be fed and watered. During hot summer days it may be necessary to sprinkle the eggs with small quantity of water to maintain the humidity. Candling may be done on 7 th days to remove the infertile eggs. The hen will take care of newly hatched chicks if they are left to the hen.Artificial Method of Incubation:-

The artificial method of incubation of eggs is known to man for more than 2000 years and the earliest records of artificial incubation are from China and Egypt. The early Chinese appear to have utilized the heat of rotting manure for hatching eggs. There are evidences that at a later stage they used charcoal fire in cylindrical oven made of earthen materials with a combined smoke hole and variable damper at the base for incubating eggs. The egg baskets held in the oven seem to have several layers of eggs, but there appears to be no note of turning the eggs in those days. The ancient Egyptians used artificial incubation on large scale. Their incubators were built of mud bricks and consisted of central corridor. On either sides of the corridor there were a series of ovens of standard pattern. The egg chambers were at ground level and had opening in corridor for attending the chicks and eggs in the chamber. Above the egg chambers were the heating compartments. Some of these incubators still exist today.

Modern Hatcheries –The modern hatchery is an impressive example of engineering solution of biological

requirements of developing embryos and production of viable and healthy chicks. There is

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perfect control of temperature, humidity, ventilation and turning of eggs under extremely hygienic condition to produce over 1 million chicks a week with relative ease from incubators equipped with sophisticated controls to maintain optimum hatchability. Hatcheries of such size and performance are not uncommon.

The credit goes to Charles A. Cypher who designed the first large size incubator for duck eggs in 1885. Smith patented the forced-draft type of incubator in 1918. In 1923, the petersime incubator Co. introduced all electric incubators. All kind of modern technologies have been utilized to save labour and improved the control performance in present day incubators.

Factors Essential for Incubation of Eggs:Five major functions are involved in the incubation and hatching of poultry eggs. They

are: Temperature Humidity Ventilation (Oxygen and Carbon dioxide level and air velocity) Position of eggs Turning of eggs

1. TemperatureTemperature is the most critical environmental concern during incubation because the

developing embryo can only withstand small fluctuations during the period. Embryo starts developing when the temperature exceeds the physiological zero.

Physiological zero is the temperature below which embryonic growth is arrested and above which it is reinitiated. The physiological zero for chicken eggs is about 75ºF (24ºC). The optimum temperature for chicken egg in the setter (for first 18 days) ranges from 99.50 to 99.75ºF and in the hatcher (last 3 days) is 98.50ºF.2. Humidity

Incubation humidity determines the rate of moisture loss from eggs during incubation. In general, the humidity is recorded as relative humidity by comparing the temperatures recorded by wet-bulb and dry-bulb thermometers. Recommended incubation relative humidity for the first 18 days ranging between 55 and 60% (in setter) and for the last 3 days ranging between 65 and 75%. Higher humidity during hatching period is given to avoid dehydration of chicks.3. Ventilation

Ventilation is important in incubators and hatchers because fresh oxygenated air is needed for the respiration (oxygen intake and carbon dioxide given off) of developing embryos from egg setting until chick removal from the incubator. The oxygen needs are small during the first few days compared to the latter stages of development. Oxygen content of the air at sea level is about 21%. Generally the oxygen content of the air in the setter remains at about 21%. For every 1% drop in oxygen there is 5% reduction in hatchability.

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Carbon dioxide is a natural by-product of metabolic processes during embryonic development and is released through the shell. The tolerance level of CO2 for the first 4 days in the setter is 0.3%. A CO2 level above 0.5% in the setter reduces hatchability and is completely lethal at 5.0%. Since the normal oxygen and CO2 concentrations present in air seem to represent an optimum gaseous environment for incubating eggs, no special provision to control these gases is necessary other than to maintain adequate circulation of fresh air at the proper temperature and humidity.4. Position of eggs

Artificially incubating eggs should be held with their large ends up. It is natural for the head of the chick to develop in the large end of the egg near the air cell, and for the developing embryo to orient itself so that the head is uppermost. When the eggs are incubated with the small end up, about 60% of the embryos will develop with the head near the small end. Thus, when the chick is ready to hatch, its beak cannot break into the air cell to initiate pulmonary respiration. Eggs positioned horizontally will incubate and hatch normally as long as they are turned frequently. Under normal circumstances eggs are set with large end up for the first 18 days (in setter) and in horizontal position for the last 3 days (in hatcher).5. Turning of eggs

Birds, including chickens and quail, turn their eggs during nest incubation. Nature provides nesting birds with the instinct of turning eggs during incubation. Similarly eggs to be turned at least 8 times a day. Turning of eggs during incubation prevents the developing embryo adhering to the extra-embryonic membranes and reduces the possibility of embryo mortality. In large commercial incubators the eggs are turned automatically each hour i.e. 24 times a day. Most eggs are turned to a position of 45° from vertical, and then reversed in the opposite direction to 45° from vertical. Rotation less than 45° are not adequate to achieve high hatchability. Turning is not required in Hatcher.

Factors Setter HatcherTemperature 99.50 to 99.75°F 98.5° FRelative Humidity 55-60 % 65-70 %Position Large end up HorizontalTurning Manual- 8 times Automatic - 24 times No turning

Handling of hatching eggs and storageThe quality of hatching egg cannot be improved after lay but one can reduce the loss in

hatching egg quality by adopting some standard procedures.

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Maintaining egg quality in the breeder houseThe hen will lay her eggs over nesting material. Use of enough clean, dry and mold-free

nesting material can avoid cracked and dirty eggs. Similarly hens to be trained to use nests to lay eggs instead of laying on floors by providing sufficient number of nest boxes well in advance before the laying starts.

The frequency of hatching egg collection is very important to maintain quality. Hatching eggs should be collected at least 4 times a day. Hatching eggs are susceptible to contamination and every effort must be made to reduce the microbial load. Therefore, it is imperative that people wash and sanitize their hands before collecting eggs from the nests or egg belts. The flats that eggs are placed on must also be sanitized and free of organic material.Selection of hatching eggs

Not all eggs laid by a breeding flock are set. Eggs that are cracked, dirty or misshapen are usually not used for hatching. Very small or very large eggs do not hatch as well as eggs in the middle size range. Eggs with thin or very porous shells are not likely to hatch well because of excessive losses of water during incubation.Reducing contamination of hatching eggs

Poor hatching egg sanitation can be a major cause of lower hatchability and poor chick quality. There is no such thing as a sterile egg shell. More bacteria are picked up on the shell when the egg passes through the cloaca where urine and intestinal contents also pass. The bacterial load found on an egg shell at the time of lay ranges from 300 to 500 organisms. After oviposition, every surface the egg comes in contact with can further inoculate the shell surface. After an egg is laid it begins to cool. During the cooling process the egg contents begin to shrink and producing negative pressure. This is one of the more opportunity times for bacteria on the shell surface to penetrate the egg shell.

Egg has many natural defense mechanisms to reduce bacterial penetration. The shell itself provides some protection. The cuticle on the surface of the egg shell is the best natural barrier to penetration. The inner and outer shell membranes provide additional barriers. The albumen provides a somewhat effective control over contamination. The albumen has a high pH in which most bacteria cannot survive. The chalazae contain an enzyme, lysozyme, which has antibacterial properties.

Many breeder people choose some methods to reduce the microbial load over the egg shell. Sanding, buffing, and wiping the hatching eggs are not good methods of sanitation. Sanding and buffing will remove at least part of the cuticle resulting in eggs that are more susceptible to penetration. Fumigation with formaldehyde gas is an effective method of sanitizing hatching eggs. Solutions containing quaternary ammonium compounds, formalin, hydrogen peroxide or phenols may be moderately effective in reducing the microbial load over hatching eggs. Do not wash eggs unless necessary. If it is necessary to wash eggs always use a damp cloth with water warmer than the egg. This causes the egg to sweat the dirt out of the pores. Never use water, cooler than the egg. Also, do not soak the eggs in water.

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Storage of hatching eggsIn normal hatchery operations, eggs cannot be set immediately after they are laid. Many

hatcheries set eggs once or twice in a week. If hatching eggs are stored up to 1 week, hatching eggs should be kept in an egg holding room with the temperature of 65oF and the relative humidity of 75%. When storing eggs less than 10 days, store them with the large end up. If eggs are held for 10 days or more, hatchability will be improved if stored with small end up.Hatchery Equipments:-

The different equipments used in the hatchery are as follows: Incubator:- A machine that creates the perfect conditions for an egg to incubate and hatch successfully.(1) Kerosene incubator:-

These are small incubators holding a maximum of 300 eggs. This incubator has a lamp light inside with a chimney. This runs on kerosene.

(2) Hot Water Incubator:- Hot water is circulated through metal pipes fitted inside the incubators. Hot water

heated outside is pumped through these metal pipes. The incubator temperature is maintained around37.7 oC.(3) Forced Draft Incubator:-

These Incubators revolutionized the poultry industry by enabling supply and

temperature is maintained inside between 99.5o and 100oF using a thermostat mechanism. A fan is provided at the back of the incubator and provides the required ventilation.

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A small incubator will hold less than 1000 eggs. A large incubator will hold 1000 to 10000 eggs. Jumbo incubators will hold 10000 to 30000 eggs. Walk in incubators will hold 30000 to 60000 eggs. Drive in incubators will hold more than 60000 eggs.

(a) Setter:-

For the first 18 days of the eggs incubation period eggs are placed in the setter.(b) Hatcher:-

The part of incubator where the eggs lay for the last 3 days of the incubation cycle.

(4) Generator:- Used for electricity purpose.

(5) Air Conditioner:- Used during summer season to keep hatchery aired.

(6) Candler:- Used in hatcher for egg candling (determining chick embryo, blood and meat spot along with

yolk).

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(7) Egg Trays:- Used after candling for keeping eggs.

(8) Fumigation Chamber:- Room in which eggs are fumigated (disinfected) after candling.

(9) Trolley:- A wheelable equipment in which setter trays of eggs are placed.

(10) Sexing Equipments:-A) Sexing turn table:-

The device is applicable for identifying the growth rate of the feather, colour of the feather

and the anus for day old chicks.

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B) Vaccinator:- Used to inject vaccine in day old chicks (0.2ml).

(11) Chick Boxes:- Sheet or plastic boxes in which the day old chicks are placed. i.e. 100 per boxes (25 rows

and 4 columns).

(12) Trucks:- DOCS (day old chicks) are loaded in it while eggs are also loaded to reach them to

hatchery.

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QUESTIONS:

1. Mention the different operations which take place in a hatchery unit?

2. Define candling? Give the importance of candling.

3. Difference between natural and artificial method of incubation?

4. Define incubation, hatching and brooding?

5. Difference between auto sexing and feather sexing in poultry?

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CHAPTER 7

MANAGEMENT OF CHICKS, GROWER AND LAYER (BROODING)Types of Brooders:-

Brooding is a mechanism of providing auxiliary or supplementary heat to chicks through artificial heat using brooders. Brooders are of several types depending upon the size and the nature of fuel used. These are individual, multiple units or central heating systems run by coal, wood, oil, gas or electricity. The essentialities of a good brooder are i) a dependable mechanism,ii) supply of fresh air, ii) dryness, iv) adequate space, v) easy for cleaning and disinfection, vi) protection against enemies, vii) safety from fire and viii) economy.i) Hover brooders:-

Such brooders are more widely used in India wherever electricity is available. They maintain uniform temperature, convenient for operation and require very little attention. However, eclectic brooders do not heat house appreciably in very cold weather. Wet litter may be another problem requiring frequent stirring and renewal of litter.

ii) Infra red brooders:-This is relatively a new method of brooding chicks in which infra red lamps are suspended 20-25 inches above the litter. These do not heat the room but warm the chicks and therefore, comfort of the chicks and not the thermometer is the guiding factor. A single 250 watts infra red bulb will provide warmth for 60-70 chicks. Multiple units may be used for brooding large number of chicks.

iii) Central heating system:-Very large highly commercial operations require central heating system for their large scale operations. Several different systems have been developed which use coal, oil, gas or electricity as fuel. Under this system heated air or water is circulated in pipe lines underneath the building to maintain warmth inside the house.

iv) Battery brooders:-It is another type of confinement brooding provided with thermostat for easy control of temperature. It will have usually 4 tires provided with feeders and water. The battery brooders must be kept within a room preferably at a temperature of 21- 24°C. Battery brooders are being extensively used for experimental purpose. Heated batteries (chick batteries) are used for brooding chicks up to 4 weeks; whereas unheated batteries (grower batteries) meant for chicks after 4 weeks.Arrangements to be made before the arrival of chicks

i) About ten days before clean, wash thoroughly, blow lamp and white wash the brooder house.

ii) Brooders, feeders, water etc. should be washed with disinfectants.iii) Put right kind of litter over the floor up to 4 inches.

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iv) Arrange the brooder one day in advance and check whether it is running properly or not.v) Spread old news papers over litter and under the brooder to avoid chicks eating litter

material by chance.Arrangements to be made after the arrival of chicksi) Depending on the necessity, chicks should have been vaccinated again Marek's disease on

the day of hatch in the hatchery itself.ii) While leaving chicks under the brooder train few chicks as how to eat and drink by dipping

their beaks in feeders and waterers.iii) The chick feed should have been supplemented with coccidiostats.iv) Follow the vaccination schedule for the chicks strictly.v) Extend chick guards as the chicks grow but remove them ultimately by 10th day.

Importance of Environment in Brooding:i) Temperature: Chicks require auxiliary or supplementary heat for the first 3 to 4 weeks of age since they are unable to adjust or regulate their body temperature in tender age. Further, proper temperature is essential for normal growth. Both low and high temperature are harmful to chicks and may slow down the growth or cause mortality. The chicks feel comfortable between 16-35°C ranges of temperature. Since it is difficult to meet individual requirements, a range of temperature between 16-35° C is to be provided allowing the chicks to adjust to the amount of temperature they need. Starting chicks immediately after hatching require 35°C during 1 st week and thereafter temperature requirement decreases by 2.5°C every week until they equal with environmental temperature of 21°C.ii) Humidity: Both high and low humidity conditions in the brooder house are undesirable. A relative humidity of 50-60% may be considered suitable. If the humidity is too high it leads to wet litter condition and certain diseases like parasites, coccidiosis may crop in. On the other hand low humidity may cause very dried up atmosphere and result in poor feathering.iii) Ventilation: Ventilation is essential to provide fresh air which is essential for developing chicks. It is also necessary to keep poultry house dry and free from odours. Proper ventilation removes poisonous gases, if any like carbon monoxide formed due to defective combustion of fuels, like oil, gas, coal etc. A concentration of 0.01% of carbon monoxide in air can initiate a slow process of poisoning. Ammonical fumes produced under deep litter system are obnoxious and irritating to the chicks in ill ventilated houses.iv) Floor space: Floor space requirements vary with the size and therefore with the age of chicks. The floor space under deep litter system is as under:0-4 weeks = 0.5 sq. ft. per chick4-8weeks = 1.0 sq. ft. per chick8-16weeks = 1.5 sq. ft. per chick16-20weeks = 2.0 sq. ft. per chick20-72weeks = 2.5 sq. ft. per chick

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Feeding and Vaccination at Early Stage of Chicks:-Brooder chick mash with 22% crude protein and 2700 Kcal/kg of metabolisable energy

has to be prepared and provided. Good quality, potable medicated water has to be provided in the water. Look for the health of the chicks at the time of delivery. Lighting for heating (brooding) has to be provided for 23 hours. Depending on seasonal requirements, adjust the length of lighting. However, layer type chicks should not be provided additional lighting for more than 12 hours after four weeks, till they start laying at 20 weeks. If day length is about 10 hours, do not give any additional lighting at all. If chicks are reared during winter and the natural day length is likely to increase as the age of the bird advances, then add giving light so as to maintain 10-12 hours per day constantly until the birds start laying. If the total length of light is allowed to increase day by day up to start of lay, such birds will start laying eggs early which will be smaller in size and will continue to remain so for longer period and thus will result in fetching lesser price and consequent loss. The required number of feeders and waterers has to be worked out and provided. Initially, smaller size feeders and waterers with lesser depth will have to be provided which should be changed to larger size with greater depth after three weeks of age.

Feed and water intake by 1000 chicks:-Age in weeks Feed intake in per

week(kg)Water intake/day (liter)

Body weight at end of the week(g)

1 40 10 602 80 25 1053 140 45 1604 200 65 2305 250 80 3006 300 95 3707 350 105 4408 390 120 510

To avoid feed wastage, the chicks are to be debeaked first at the age of 7-10 days. Their beaks have to be cut short by debeaking machine applying electrical cauterization. It may also be performed at the end of second week and repeated at 12-14th week. The upper beak has to be cut at 2/3rd and the lower beak at 1/3rd portion. The cut portion has to be cauterized by touching on the hot plate. The tongue should be carefully held back. Undertake debeaking during cooler parts of the day. Provide anti-stress B-complex vitamins and vitamin K in drinking water before, during and after the day of debeaking. Utmost care need to be taken to avoid stress during debeaking. Since layer chicks are comparatively more active, they tend to peck at each other's back (cannibalism), cause injury and death also. Debeaking helps to prevent such instances. Vaccines to be given to the birds at this brooder stage. Ensure proper dosage as per specifications. Vaccinate the birds with minimum stress to them. Medication for layer chicks include glucose and electrolytes on the first day and a mild antibiotic/antibacterial along with vitamin tonics for the first five days; later on, no medication is required unless warranted. Chicks can also be reared in cages from 0-8

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weeks. For 100 numbers of chicks the dimension of the cage should be 180 x 90 x 30 (L x B xH) cm which can be kept 75 cm above floor level. One 100 watt bulb is sufficient on the top of the cage for providing heat for first three weeks. For first two weeks, small feeders and waterers have to be kept inside the cage and afterwards they may be fixed outside on the sides of the cage. Care and Management of Commercial Growers (9-20 weeks) Under Deep Litter System

Grower management essentially remains the same as that of chick management (brooding management) except for the additional space required for floor, feeders and water to keep with the size of birds. The growers may be reared in separate grower-houses or continued to be reared in brooder-cum-grower houses.

Floor space: 1260 cm (1.4 sq.ft) per bird. Feeder space: 6-8 cm per bird. One linear feeder of 120 cm length and 8 cm depth for 40

growers. Waterer space: 2 cm per bird; a circular water of 36 cm and 8 cm depth of 6 liter capacity

for 50 growers. Growers are to be provided with fresh, cool and potable drinking water at least twice a day. Water requirement is increased during hot days. Care must be made not to spill water on litter.

Lighting management: No artificial lighting is given other than natural day light since they require only 9 hours of light per day.Growers may be fed with mash containing 16% CP and 2600 Kcal/kg ME. A bird may

take 60-80 g feed per day. The height of feeder and water should be adjusted at shoulder level of the bird. It is not advisable to provide ad libitum feeding during growing stage as the bird may put more fat affecting egg laying rate in future. Therefore, restricted feeding programme should be adopted which will delay early sexual maturity so as to improve egg quality. The litter is raked often to bring down its moisture level. If necessary, super phosphate may be mixed with litter @ 2 kg/100 ft area to reduce litter ammonia level. The birds may be dewormed at 16 th week of age with appropriate dewormer. For efficient use, 2 hour withdrawal period is practiced before offering medicated water. The poorly grown birds are to be culled at this stage. The mortality rate during growing period must be lower than 3 per cent.Care and Management of Commercial Growers (09-20 weeks) Under Cage System

For caged growers the floor may be made up to welded mesh of 1.25x5.0 cm size. In a cage of 180x90 cm size, 50 growers can be reared with a space allowance of 325 cm/bird. Feeders and waterers can be fitted lengthwise on the outside one below the other. Nipple drinker may be fitted inside the cage; adequate care should be made to maintain uniformity of growth in the flock. Sample weight should be taken once in week to find out the average body weight as per the breeder recommendations.Care and Management of Commercial Layers (21-72 weeks) Under Deep Litter System

At the end of 18th week growers are transferred to layer house to take special care so that optimum numbers of eggs are produced by them. They may be reared on good quality litter (5-6 cm height) with floor space allowance of 1800 cm (2 sq.ft) per bird. In high humid areas like north-east India the space may be increased to 2250 cm2 (2.5 sq.ft). The feeder space and waterer space allowances of 10-12 cm and 2.5 cm per bird respectively may be provided.

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A liner feeder of 180 cm length and 10 cm depth will be sufficient for 35 birds; whereas, a circular waterer of 45 cm diameter and 7 cm depth will be required for 50 birds. These birds are fed with layer mash containing 18% CP, 2700 Kcal/kg ME, 2.75% calcium and 0.80% available phosphorus, all the time. Water guards on water and grill on linear feeder will prevent birds standing on the edge or on top and spoiling the contents. Provide clean, fresh water at least twice a day. During laying stage 1000 birds will drink 250 liters of water and will consume 110-120 kg feed per day, approximately. The water consumption increased during hot days; whereas, feed consumption decreases. During cold season the feed consumption increases. The feeders and waterers are to be arranged alternatively at equal distance keeping their height at bird's shoulder level filing only to 2/3rd level to avoid wastage/spillage. The wastage is about 25 to 30% when filled full and about only 10% when filled two third. The feeders should be distributed in a way that the birds do not have to walk more than 3 meters (10ft) for feed.

Usually one nest box for every 5 layers is sufficient. The boxes may be made of GI, aluminium or wood and adjusted at about 45 cm height and kept in darker part of the shed. The mouth of the box should be of 30cm width with a depth of 20 cm. Clean litter material may be spared inside the box all the time so as to obtain clean eggs. It is better to provide community nest rather individual nest. The nest should be closed during night hours so as to prevent sitting of birds in the nest. In deep-litter system, the litter materials should be treated chemically at least once in a month so as to reduce ammonia emission it is preferably be racked in the evening, daily after the collection of eggs. Deworming should be done regularly at an interval of 6-8 weeks.Lighting Management for Layers

From 20th week or from the commencement of 5% egg production, whichever is earlier, artificial lighting should be commenced. For every week the lighting period should be increased by 15 minutes till a maximum of 16 hours of photoperiod per day is reached which is known as step up lighting programme. Beyond 16 hours of total photoperiod (natural + artificial) has no beneficial effect. Never decrease the photoperiod during laying period and never increase during non-laying period. One watt per 3 sq.ft is recommended. Bulbs of 25 to 40 watt should be firmly attached 7 ft above the floor and 8-12 ft apart. The distance between 2 tube lights (florescent) should be 15 ft. Reflectors should be used to direct all light downward and be cleaned regularly to remove dust from bulbs. The light intensity should be uniform throughout the poultry house. A light intensity of 0.5 to 1 foot candle is sufficient for egg production. Unlike incandescent bulb florescent bulbs produce a lower intensity of light as they age. The use of compact florescent lamp (CFL) not only saves electricity but also does not emit heat as comparison to its incandescent counterpart.Cage System for Layers

Layers are invariably reared in cages. Cages of various sizes are available to house 3-5 birds in a cage. Currently, reverse cages are commonly used their longer side being fitted to

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remain in the front. Further, raised platform houses are constructed, of late, to facilitate quicker drying of droppings their easy removal.

45x30cm For 3 birds45x40cm For 4 birds50x35cm For 4 birds55x45cm For 5 birds60x37.5cm For 5 birds

These cages are arranged in two or three rows one above the other on either side. If they are arranged in staircase manner, then they are termed as Californian cages. A floor space of 420- 450 cm is allowed within cages. Conventionally, the bottom of the lower most cages is fitted at 75cm height from the floor. Now-a-days, they are fitted at 120-240 cm height above the floor level with walking platforms constructed on the sides. The layer cage will be of 40 cm height. The floor is fitted with 2.5x5.0 cm size weld mesh of 14 gauge thickness. On sides, 7.5x7.5 cm size mesh of 16 gauge thickness is fitted. The bottom floor is provided with 1/6 slope downwards to the front to facilitate rolling of the eggs to the cage front. The mesh rails on cage floor should run from back to front and not sideways; otherwise they will block free run of the eggs downwards to the front. Water is fitted above the feeders in the front. Automatic water nipples/ buttons and feeders may be provided to the cages.

Cages are fitted in two or three tiers on either side of the row under Californian system of arrangement. Two to three such rows of cages are arranged in a caged layer house. Depending on the number of rows, and number of tiers in each row, the breadth of caged layer house ranges from 15-17' (5-8 m). There is no stipulation for length of such houses which can be adjusted as per the number of birds to be housed. No side walls are required for cage houses with the mesh being stretched down to the floor level to facilitate better ventilation for drying up the moisture in the droppings. Cage rearing facilitates easy management, lesser space requirement, and easier collection of eggs, less percentage of broken eggs, better egg weight, clean egg production, easy culling and reduced mortality levels.

Egg laying starts at 21 week and the rate of laying (percentage production) increases every week to reach a level of 90% and above after 28 weeks of age which is maintained well beyond 36 weeks of age even up to 40-42 weeks. Afterwards, it slumps down slowly to reach 70% or below by 72 weeks of age. When the egg production goes below 65%, it is uneconomical to retain them unless the egg price is exceptionally high.

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QUESTIONS:

1. What are the different types of brooder? Explain in detail.

2. What are the arrangements needed before and after the arrival of chicks to the brooder

house?

3. Write about the environmental conditions needed for proper brooding of chicks?

4. Write about care and management of grower and layer birds, respectively.

5. Write short notes on egg laying pattern in layer birds and California cage system.

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CHAPTER 8

DEBEAKING AND DUBBING

DEBEAKING: Debeaking is the partial removal of the beak of poultry, especially layer hens and turkeys

although it may also be performed on quail and ducks. Most commonly, the beak is shortened permanently, although regrowth can occur. The trimmed lower beak is somewhat longer than the upper beak.

METHODS OF DEBEAKING: There are several methods available for beak trimming.Hot blade (4-5 days of age) The most commonly used method is beak trimming by means of a hot blade. This method

is usually practiced when the birds are 4-5 days of age. Important with this method is that the blade is warm enough for immediate cauterization of the wound. The blade is hot enough when the center is cherry-red hot. To stimulate cauterization, the house temperature is usually dropped during the debeaking process, as lower temperature helps to stop the bleeding.

Automated hot blade (4-5 days of age) To have a uniform debeaking procedure, sometimes a plate with a hole in front of the blade

is used. This prevents that the beak is pushed-in too far. When a plate with a hole is used, sometimes the birds are fixed with special equipment that holds the head in a standard position. This is called a debeaking automat. Whenever this type of equipment is used, it is

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important that it is adjusted to the actual size of the flock, and that the flock is uniform in development, to provide a uniform beak trimming.

Laser, infra-red or microwave (hatchery) Debeaking can also be done in the hatchery. With this method, a pulse of high energy is

sent through the tip of the beak, either by means of an infra-red beam, an electric current, a microwave beam or a laser beam.

This pulse of high energy, damages the tissue in the tip of the beak and as a result, the tip of the beak falls-off after a few days.

Although this treatment seems to cause less stress for the birds, there is a risk of retarded growth after a few days, especially when small birds are beak trimmed. This retarded growth seems to be caused by a more sensitive beak tip, indicating some development of pain.

Importance of Debeaking:Beak trimming is a preventive measure to reduce damage caused by injurious pecking

such as cannibalism, feather pecking and vent pecking, and thereby improve livability.POINTS TO OBSERVE DURING DEBEAKING:

Remove feed 3-4 hours before debeaking Supply water and feed after debeaking Don’t use old blade during debeaking Don’t debeak under extreme temperature of shade Check beak before production starts Birds with too long beaks or very long lower beak should be trimmed again Blade should be cherry red too hot blade gives bad result

DUBBING

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Dubbing is the procedure of removing the comb, wattles and sometimes earlobes of poultry. Removing the wattles is sometimes called "dewattling".

PROCEDURE OF DUBBING: To perform dubbing, the tissues are first disinfected and, if available, an anesthetic is

applied to limit pain. Sterile scissors or dubbing shears are used to cut the tissues off, and a styptic, an astringent chemical that reduces bleeding, is applied.

The wounds are left uncovered. Some recommend dubbing should be done on day old chicks whilst others advise waiting until the bird's comb is more developed.OBJECTIVE OF DUBBING:

Dubbing (cutting off combs and wattles of chickens prevents damage from freezing and fighting. The comb may be removed at day-old, but it is less difficult to remove the wattles if you wait until the birds are 4-6 weeks of age.BENEFITS:

Dubbing is sometimes performed to limit damage caused by injury or frostbite. Dubbing for some breeds has become a tradition and is required for some birds to meet

breed-specifications. Other reasons include removing combs which have become so large they prevent the bird

from taking food into its mouth or making the head so heavy it sinks into the bird's chest. In the US, the National Chicken Council (2003) listed dubbing of cockerels as one of the

acceptable procedures that may cause short-term stress but which are necessary for the long-term welfare of the flock.

Dubbing is also performed to prevent injuries from other birds or while being kept in pens.

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QUESTIONS:

1. What are the objectives of dubbing and debeaking process in poultry?

2. Explain in detail the different methods used for dubbing and debeaking?

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CHAPTER 9

ECONOMICS OF POULTRY PRODUCTION

ECONOMIC TRAITS OF LAYER FARMING:-

1. Egg Production The egg production of a chicken is a result of many genes. With appropriate

environmental conditions (nutrition, light, ambient temperature, water, free from diseases etc.), the many genes controlling all the processes associated with egg production can act to allow the chicken to fully express its genetic potential.

Generally the egg production is considered as a composite trait largely influenced by five characteristics.

They are age at sexual maturity, Intensity of production or rate of laying, Broodiness, Clutch size and pauses in laying and Persistency of production.

The egg production can be measured as follows: Hen housed egg production per bird = Number of eggs laid

Number of birds housed Hen housed egg production (%) = Number of eggs laid × 100 ÷ Number of birds housed Hen day egg production (%)= Number of eggs laid÷ Number of hen days Hen day egg production per bird= Number of eggs laid ÷ Average hen days Average hen days = Total hen days ÷ Number of days

Egg production is a lowly heritable trait. To produce a hybrid cross having good egg number along with egg weight, one of the parent lines (usually female) is selected exclusively for egg number, while the other line is selected for both egg weight and egg production.1] Age at Sexual Maturity (ASM)

This can be defined as the age in days when the bird laid its first egg and in chicken, the age at sexual maturity is around 150 days. Very early maturity is also not preferred as it results in the production of small sized eggs and a very late maturity is also not ideal either, as it ends up with less number of eggs. Early maturity increases the incidences like uterine prolapse and other complications. Sometimes the pullets are prevented by restricting light and feed to delay eggs at an early age so that production of small size eggs could be prevented. ASM is a moderately heritable trait ranging from 0.15-0.25.

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2] Intensity of Laying (Rate of Lay) This trait is an important contributing factor to the annual egg record. This is the ability

of birds to lay at a high rate at any given point or a period of time. It has been found that hens at high intensity of lay produce larger number of eggs per clutch and are usually better layers than birds which lay fewer eggs per clutch. The rate of laying is lowly heritable. The rate of laying can be measured in terms of hen-day and hen-housed egg production.3) Broodiness

When the birds are in brooding stage they are not laying. Hence, a minimum of broodiness is desired. The Mediterranean breeds like White Leghorn, Minorca, Ancona and a few others are on the whole non-broody, whereas the heavy breeds or Asiatic breeds are very broody. English and American breeds derived from these contrasting groups are usually intermediate in broodiness. This trait is highly heritable and therefore can be eliminated by selection.

Broodiness has high negative correlation with the egg production. Therefore, when a stock is selected for egg production, this character is eliminated from the flock. Modern commercial egg laying strains are devoid of this character. However, broodiness and mothering ability are the two desirable characters in poultry for backyard rearing for self replication and survival.4] Persistency

Persistency is a measure of the length of a laying year. The laying is ordinarily terminated around 72 weeks of age and this is called laying cycle or biological cycle. After this the bird will enter into moulting, a physiological process by which the old feather are shed and renewed with new ones. During this process the bird will go out of production before entering into the next cycle of laying. In commercial layers, birds are culled after first biological cycle as they are uneconomical in the subsequent cycles. The good layer moults late and rapid. While the poor layer is early and a slow moulter.

Fecundity is the another term which may be defined as the number of eggs produced in an agreed period of time regardless of other characters such as egg size, hatchability etc. In practice this period is considered as pullet year.5] Clutch Size and Pause

The eggs are laid in daily sequence and the number of the egg laid in the sequence without any break is called as clutch size. The bird will skip a day or two from production before entering in to the nest clutch. In good producer, the clutch size is big with a short clutch interval.

When this interval is considerably long, then, this is called as pause. Pause is not a desirable character in good layers. The bird may pause producing eggs in climatic extremities like winter and summer. Selection for high annual egg production ends up the elimination of this character from the population. The low producers and desi birds usually have frequent pauses, during which period they exhibit the maternal behaviour or broodiness.

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2. Egg Size This is measured in terms of egg weight. There appears to be a direct relationship

between body size of birds and the size of the eggs laid. Eggs are smaller in the beginning of laying and there is gradual and steady increase in size for 6 to 7 months. Considerable variation in size of eggs has been observed between breeds, strains and lines. The egg weight varies from 40 to 60 grams and the heritability of the trait is approximately 50 per cent (0.5). Therefore genetic improvement for this trait can easily be brought in a population by individual selection. However, its strong negative correlation with egg number necessitates a careful approach in breeding programmes. In cross breeding programmes, the pressure for egg weight is usually given in the male line.3. Egg Colour

The Mediterranean class of chicken lay white eggs and most of the other class of chicken lay brown eggs. The shell colour in Andalusian chicken is blue. The cross between chickens of brown and white eggs will produce tinted or light brown shell colour. To evolve a white egg layer, the common breed used is White Leghorn. Different elite strains of this breed can be crossed to produce a hybrid white egg layer. For brown eggs, breeds like RIR, Plymouth Rock and New Hampshire are used in different combinations.4. Feed Efficiency

In commercial layers, the feed efficiency of per kilogram egg mass and of a dozen eggs is around 2.35 and I.70 respectively. Measuring feed efficiency by recording individual feed intake is laborious and therefore selection for feed efficiency is also impractical. Both egg production and egg weight have a high positive correlation with feed efficiency, therefore, selection for these characters improves feed efficiency as a correlated response.5. Body Weight

The body weights at maturity (20 weeks) as well as of adult (40 weeks) are of significance in layer breeding. The optimum mature and adult body weights for medium egg type layer are 1.2 and 1.6 kg respectively. Selection for egg weight tends to increase the body weight as these traits are positively correlated. Restricted selection index can be used to check any untoward change in body weight.6. Egg Quality Traits

Egg quality characters like shell thickness, albumen index, Haugh unit and blood and meat spots are lowly heritable traits. Nevertheless they are not included in the selection programmes also. Shell thickness is the only quality trait which is having economic importance and this trait is negatively correlated with the size of the egg.7. Viability

One of the most serious problems confronting in layer production is the mortality among laying pullets. Both genetic defects and infectious diseases are causes of death. Gross genetic defects are not a matter of concern as they are usually eliminated. However, efforts are required for breeding and selection of stains resistance to infectious diseases. Strains as well as crosses differ considerably in their susceptibility to different diseases. Mortality rates of 5 and 3 % are allowable at chick and grower stages. At layer stage mortality rate of one per cent per month is

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permissible.8. Fertility and Hatchability

It is difficult to distinguish between low fertility and high incidence of embryonic death. Therefore, fertility and hatchability of fertile eggs are usually considered together as hatchability of eggs set. The heritability of fertility and hatchability is very low.9. Sex-Linked Dwarfism

Dwarfism, which causes an animal to be subnormal in size, is well known in chickens. Both egg producers and broiler producers are interested in sex-linked dwarfism. Hens that carry the sex-linked dwarf genes are about one third smaller than normal body size, but their egg size is about 8% smaller. The objectives in these 'mini' layers are to lower body maintenance requirements and thereby increase the efficiency of feed utilization.

ECONOMICS OF POULTRY PRODUCTION (BROILER)Meat Type Chicken

In broilers, the trait of utmost importance is body weight at marketing age or juvenile body weight.

The other traits of importance in selection programmes are body conformation and hatching egg production in the parent line. In broiler breeding, the female line should be one which produces high number of chicks. Therefore apart from juvenile body weight, the female parent line is also selected for hatching egg production.

The other traits like colour of skin, plumage colour and rate of feathering in the hybrid can be decided by using appropriate breeds/strains in the breeding programme. Compared to layer, broiler breeding is relatively easier because selection can be done as early as 6 weeks of age based on the body weight.

Body Weight It is one of the most important characters of broiler production, and it is highly heritable

at marketing age. Therefore, it is relatively easy to make progress genetically by individual selection. It is

easy to measure and it is also known to be positively correlated with body conformation, feed efficiency and dressing loss.

Hence if the growth rate is improved other carcass quality characters will also improve. However, it should be remain in mind that body weight is negatively correlated with egg

production. Separate lines of males and females are developed with considerable high pressure of

selection on body weight and egg production. Feed Efficiency In modern commercial broilers, a feed efficiency of 1.6-1.8 is achievable at sixth week of

age. Measurement of feed efficiency on individual basis in breeding stock is very difficult and

laborious therefore its inclusion in the selection programmes is also not possible. However, selection for growth rate automatically improves feed efficiency since both the

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traits are highly positively correlated.

Meat Yield Meat yield can be expressed as carcass yield or dressing percentage, yield of specific

carcass parts and yield of specific tissues such as lean, fat, skin and bone. Meat quality can be assessed by several methods: by carcass conformation or grade,

sensory evaluation or flavor, juiciness and tenderness of the cooked carcass or carcass part and by chemical composition of the carcass to determine the amounts or proportions of protein, fat, moisture and ash.

Carcass yield or dressing percentage is expressed as weight of the carcass as a percentage of the weight of the live chicken.

Viability In commercial broilers under standard management, mortality rates of 3 and 2% are

allowable, respectively at starter and finisher stages. Mortality in broilers involves susceptibility to common diseases of early age like

Pullorum, Coccidiosis and New Castle disease etc. Body Conformation

The body conformation traits include breast angle, keel length, shank length, breast meat yield, abdominal fat percentage, overall appearance etc.

Conformation traits improve when the stock is selected for body weight as both are positively correlated.

The ideal meat bird is having plump body with, a long, broad and heavily fleshed breast. The back must be broad and heavily fleshed with minimum abdominal fat. Breast is low

in fat therefore fetches high price than other retail cuts; therefore the parents are selected for higher percentage of breast muscle yield.

Skin Colour The skin colour is inherited by complete dominance where, white colour is dominant to

yellow. The common breeds used in evolving commercial broilers such as Cornish, Plymouth

Rock and New Hampshire are yellow skinned. Therefore developing a yellow skinned broiler is practically simple. For developing a white skinned broiler, Sussex, an English breed with white skin can be

included in the breeding programme as a female line. Plumage Colour

Although both melanin and carotenoid pigments contribute to the feather color of certain avian species, it is the melanin that determines the plumage color and patterns of the domestic fowl.

Each plumage color and pattern is the result of a series of genetically determined events, and an awareness of these facilities understanding its inheritance.

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Fertility and Hatchability All the reproductive characters including fertility and hatchability are lowly heritable. The fertility and hatchability rates are very less in broilers compared to layers as these

traits are negatively correlated with body size. English breed Cornish is the common male line in broiler breeding. Though this breed is

good in conformation characters, the reproductive traits are at the lowest among the poultry breeds. Therefore special attention has to be given to improve the fertility in breeding programmes.

Rate of Feathering Slow feathering birds have a large number of pin feathers. Early feathering is one of the desirable characteristics in broilers avoiding the problem of

pin feathers at the time of processing. Rate of feathering is inherited by sex-linked dominance, in which, slow feathering is

dominant to fast feathering. Making all the lines involved in crossing as homozygous recessive for rate of feathering

(kk) can ensure this character in all the progenies.

PROJECT REPORT ON LAYER FARMING (1000 LAYERS)Introduction

Poultry egg and meat are important sources of high quality proteins, minerals and vitamins to balance the human diet. Commercial layer strains are now available with traits of high egg production and high feed conversion efficiency. Superior germplasm of chicken have been developed by both public and private sectors which met the requirement of Indian Poultry Industry. Depending on the farm-size, layer (for eggs) farming can be main source of family income or can provide income and gainful employment to farmers throughout the year. Poultry litter has high manure value and can be used for increasing yield of all crops.Scope for Layer Farming and it’s National Importance

Poultry is one of the fastest growing segments of the agricultural sector in India today. In the poultry industry, value added products utilizing poultry eggs, culled birds for human consumption have been developed. However only 6% of the eggs produced in the country are converted into processed egg products mainly for export.

The poultry sector in India has undergone a paradigm shift in structure and operation. This transformation has involved sizable investments in breeding, hatching, rearing and processing. Farmers in India have moved from rearing non-descript birds to rearing hybrids which ensures faster growth, good livability, excellent feed conversion, high egg production and profits to the rearers. High quality chicks, equipment, vaccines and medicines are now available through both public and private players. Technically and professionally competent guidance is available to the farmers. The managerial practices have improved and disease and mortality incidences are reduced to a great extent. The industry has grown largely due to the initiative of private enterprises, government intervention, and considerable indigenous poultry genetic

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capabilities and adequate support from the complementary veterinary health, poultry feed, poultry equipments and poultry processing sectors.Financial assistance available from banks

Loan from banks with refinance facility from NABARD is available for starting poultry farming. For poultry farming schemes with very large outlays, detailed project reports will have to be prepared. Banks provide financial assistance for the following purposes:

1. For construction of brooder/grower and layer sheds, feed store, quarters etc.2. For purchase of poultry equipment such as feeders, waterers, brooders etc.3. For creating infrastructure items for supply of electricity, feed, water etc.4. For purchase of day old chicks or ready to lay pullets.5. For meeting working capital requirement in respect of feed, medicines and veterinary aid

etc. for the first 5 to 6 months (i.e. till the stage of income generation).For high value projects, the borrowers can utilize the services of NABARD Consultancy Services (NABCONS) who are having wide experience in preparation of Detailed Project Reports.Scheme formulation for bank loan

A scheme can be prepared by the beneficiary after consulting local technical persons of state animal husbandry/veterinary department, poultry corporation or private commercial hatcheries. If possible, they should also visit the progressive layer farms in the area and discuss the profitability of farming. A good practical training and experience on a layer farm will be highly desirable, before starting a farm.

The project should include the following information on technical, financial and managerial aspects in detail.

Technical1. Land and land development (Location, area, suitability, proximity to road, site map etc.)2. Proposed capacity/farm size3. Civil structures (Sheds, feed mixing unit, egg room, godown/store room, office quarters,

staff room etc.)4. Equipments, plant and machinery – (Feeder, waterer, cages, feed grinder and mixer, Deep

freezer, vaccinator, debeaker etc.)5. Housing (Capacity, type- Deep litter/Cage, Area required, and system of housing (1 + 2,

1 + 3, 1 + 1 + 2 etc.)6. Chicks – (Strain, number of birds/batch strength, source of chicks, vaccination of chicks

etc.)7. Feeding (Feed requirement, source of feed, type of feed – chick, grower and layer mash,

price of feed etc.)8. Availability of utilities – Water, power and fuel9. Veterinary aid and transportation arrangements10. Production parameters (Egg production, Feed efficiency - FCR, Mortality etc.)11. Flock projection chart

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12. Marketing (Marketing of eggs/culled birds and other products/by-products – place of marketing, basis of payment (kg or no.), price per unit etc.)

Financial1. Project cost - capital (Land, building, chicks, plant and machinery etc.) and recurring costs2. Funding pattern (Margin contribution, bank loan, etc.)3. Techno-economic assumptions4. Income – expenditure statement5. Cash flow analysis showing financial indicators (IRR, NPW, BCR and DSCR)6. Analysis of ratios (DER, ROCE, current ratio, etc.)7. Repayment schedule indicating repayment of principal and payment of interest

Managerial Borrower's profile

1. Individual/Partnership/Company/Corporation/Co-operative Society/Others2. Capability in managing the proposed business3. Experience in the proposed activity or others4. Financial soundness5. Technical/Other special qualifications6. Technical/Managerial Staff and adequacy thereof.

Others1. Name of the financing bank branch2. Training facilities3. Assistance available from State/Central Government4. Regulatory clearances, if any etc.

Appraisal of the projectThe project so formulated considering the above mentioned aspects should be submitted

to the nearest branch of the bank for availing credit facility for establishment of the layer farm. The bank will then examine the project for its technical feasibility, financial viability and bankability.Sanction of bank loan and its disbursement

After ensuring technical feasibility and financial viability, the loan is sanctioned by the bank. The loan is disbursed in stages viz., construction of sheds/other civil structures, purchase of equipment and machinery, recurring cost on purchase of chicks, feeds, medicines, etc. The end use of the loan is verified and constant follow up/monitoring is done by the bank.Lending terms - GeneralOutlay: Outlay of the project depends on the local conditions, unit size and the investment components included in the project. Prevailing market prices/cost may be considered to arrive at the outlay.Margin Money: Margin depends on the category of the borrowers and may range from 10% to 25%.

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Interest Rate: Banks are free to decide the interest rates within overall RBI guidelines. However, for working out financial viability and bankability of model project, the rate of interest is assumed at 12.50% p.a.Security: Security will be as per RBI/NABARD guidelines issued from time to time. Repayment period of loan: Repayment period depends upon the gross surplus from the project. The loan will be repaid in suitable monthly/quarterly installments usually within a period of seven to nine years with first year as grace period.Insurance: The birds and other assets (poultry sheds, equipment) may be insured. Wherever necessary, risk/mortality fund may be considered in lieu of insurance.

PROJECT REPORT OF 1000 LAYER FARMING FIXED COST

Land cost = Owned land Shed construction cost =Required area is 850 square feet

@Rs.150/square feet=150× 850

=1,27,500/ Cost of cages =@Rs. 50/bird

=50× 1000 =50,000/

Cost of brooder/grower house construction =Required area is 600 square feet @Rs. 120/square feet

=600× 120 =72,000/

Cost of equipments [chick guard, wheel barrows, waterers, grower feeder, debeaker] =50,000

Cost of chick purchase @Rs. 40/chick =40× 1000 =40,000/

TOTAL FIXED COST=1,27,500+50,000+72,000+50,000+40,000 = 3,39,500/VARIABLE COST

Cost of electricity, water and others = @Rs. 1000/month=1000× 12=12000.00

Cost of feeding i] Chick phase = @Rs. 1.8kg/ chickAnd 1 kg feed price is 20 Rupees

=1.8× 1000 × 20=36,000.00

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ii] Grower phase = @Rs.20/kg and 5.5 kg/bird but mortality is 4% so, number of grower

Remain = 960=5.5× 960 × 20 =1,05,600.00

iii]Layer phase = @40 kg/bird and @Rs. 20/kg = 40× 960 × 20 = 7,68,000.00

Cost of vaccination and medication = @Rs. 10/bird=10× 960

=9,600.00 Cost of labour =@Rs. 5,000/month/labour and

labour requirement=01 =01× 5000 × 12 =60,000.00

T0TAL VARIABLE COST=12,000+36,000+1,05,600+7,68,000+9,600+60,000 = 9,91,200/

INCOME GENERATION Sale of eggs = @300 eggs/bird and egg price is Rs. 04/egg

=300×960 × 04=11,52,000/

Sale of manure= @Rs. 100/bird=100×960=96,000/

Sale of gunny bags = 5,000/ Sale of spent hens = number of spent hens is 960 @Rs. 100/hen

=960×100 = 96,000.00 TOTAL INCOME GENERATION =1152000+96000+5000+96,000 =13,49,000.00 Difference=Total income – [Fixed cost+ Variable cost]

=1349000-[339500+991200=1330700] 18,300/ [Profit in first year].

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QUESTIONS:

1. Write the important economic traits of layer birds.

2. Write the important economic traits of broiler birds.

3. Prepare a project of 1000 broiler birds for 6 batches in a year with final cost

benefit analysis.

4. Prepare a project of 5000 layer birds with final cost benefit analysis.

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CHAPTER 10

PRESERVATION OF EGGS

Preservation and Maintenance of the Egg Shell QualityIn considering the preservation of the eggs quality, it is assumed that the chicken egg is at its highest quality at the time of laying. Anything done to the egg later results in quality loss.

Shell quality characteristics that must be considered are cleanliness, soundness, smoothness, and shape. Two most desirable shell qualities (cleanliness and soundness) are largely controlled by production and egg handling practices.

All preservation methods for shell eggs have been designed to retard one or more of the following physico-chemical alterations which lowers the quality of eggs as it ages.Physico Chemical Changes During Storage of EggsAs soon as an egg is laid its quality starts to decline. With present knowledge of physical and chemical structure of the egg all that can be done is to delay the decline of the egg quality. As the warm egg cools its contents contract and air cell is formed. At the same time mucus like coating on the shell commonly called cuticle or bloom dries on the surface and begin to dry in the calcium pores of the shell. As the cuticle dries it shrinks, the size of the pores increases and makes easy for the gases and micro organisms to pass in and out of the shell.

Egg white or albumen gives off carbon dioxide which passes through the pores of the shell. During first few hours after an egg is laid the rate of the carbon dioxide is held in the white as a weak solution of carbonic acid. As the carbon dioxide escapes, the carbonic acid break down and supplies more carbon dioxide and water.

The breakdown of carbonic acid in the egg white causes to change from neutral media (about pH 7.6) to one of the most alkaline biological fluids known (pH 9.7). As the egg white loses the carbon dioxide and pH changes, the mucin fibers which give egg white its gel texture lose their structure and the egg white becomes watery.

A yolk absorbs water from the albumen although the vitelline membrane surrounding the yolk separate it from the albumen, water moves through the vitelline membrane from the albumen into the yolk in an attempt to equalize the difference in concentration between the two fluids, as the yolk absorbs water, it swells and exerts pressure on the vitelline membrane. This pressure causes the yolk to change from spherical shape to round flabby mass.

While the yolk is absorbing water from the albumen, water is also evaporating from the albumen through the shell pores. Eventually as deterioration progresses, the concentration of the water in the albumen become greater than the yolk and begins to move back into the albumen from the yolk. The egg becomes an inedible product when either yolk settles to the bottom or side of the shell and gets attached in such case it will be rejected as stuck yolk, or the vitelline membrane breaks and the egg becomes a mixed rot.

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Methods to Retard the Egg Quality:All the methods of preservation depend on retarding one or more of the above series of events. The use of any method of preserving requires compromise.The following preservation methods were employed to maintain the quality of shells eggs.

Egg cleaning Oil treatment Cold storage Thermo stabilization Immersion in liquids Pickling

Egg cleaning:All stained or dirty shells can be cleaned by two methods(A) Dry cleaning and (B) Wet cleaning Dry Cleaning:

This was the recommended practice before the development of sanitizing compounds capable of maintaining washing water and equipment in a condition so that wet cleaning methods could be used. The simplest dry cleaners are hand abrasive blocks to scratch the dirt or stain from the shell surface. Abrasives were put on mechanically rotated wheels so that eggs could be rapidly cleaned by holding individual eggs against the rotating abrasive surface. Although mechanical equipment for dry cleaning shell eggs was developed it has been made obsolete by wet cleaning procedures.

Disadvantage of dry cleaning is weakness of the shell. Only dirty and unsound eggs should be cleaned. Wet Cleaning

For clean appearance of eggs, washing is more effective and simplest method for removing dirt and stains from the shell surface. Egg wash water temperature need to be at least 10oC higher than egg temperature. The temperature differential between the eggs and wash water also critical, as a difference of more than 10oC results in increased number of thermal cracks due to expansion of contents of egg. In older eggs with enlarged air cells, the thermal checking is not a serious problem. Also a water temperature of at least of 35oC (95°F) is needed for adequate cleaning. By not recycling water and by giving careful attention to the temperature difference between eggs and wash water eggs can cleaned with a minimum of hazard to quality.Disadvantage:

There is possibility of bacterial penetration of the shells, with resultant rotten eggs. A temperature difference of more than 10oC results in an increased number of thermal cracks due to expansion of contents of the egg.

Cold eggs subject to hot water will expand too fast and crack the shell (expansion checks) on the other hand the interior contents of eggs that have been washed in hot water and then rinsed by immersion in cold water contract and aspirate bacteria through shell. The organisms multiply and the eggs spoil.

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Modern egg washers are designed to minimize the above conditions by spraying water, rather than immersing them using a sanitizer in water along with detergent for cleaning them using rinse water warmer than the wash water and finally dry the eggs with hot air. Oil Treatment:

Oil coating preserves the egg by forming a thin film on the surface of the shell and thereby sealing the pores. The treatment should preferably be given within a few hours of lay to retain better internal quality. Washing and subsequent coating preserve eggs much better than coating alone. The oil used must be odourless, colourless and free from fluorescent materials. Light mineral oil of food quality is normally used.

BHT is a good sealing agent. Mineral oils of food grade are less susceptible to oxidative changes during storage. Eggs can either dipped in oil or sprayed with it. Immersion in Liquids:

Under village conditions liquids like lime water is very useful. This is old method of preserving the quality of shell eggs especially for home use.

In lime sealing, one liter of boiling water is added to one kg of quick lime. The fluid is brought to room temperature, and 4-5 liters of cold water and 250g of table salt are added to it. On the mixture setting down the solution is strained. The eggs are immersed in thin clear fluid for 16-18 hours, and then taken out. Eggs are dried at room temperature and transferred to filler flats. The eggs can be stored for 3 to 4 weeks at room temperature.

The preservative effect of the lime water is partially due to its alkalinity. It deposits a thin film of calcium carbonate on the egg shell and partially seals the pores. The water glass is prepared by diluting 1 part of sodium silicate with 10 parts of water and the eggs are left immersed over right in water glass. It deposits a thin precipitate of silica on the surface of egg shell, possesses intrinsic antiseptic properties and does not impart odour or taste to the eggs.

When started at 10 to 130C (34 to 370F) the water glass preserved eggs were comparable to fresh eggs in all attributes. Egg can be stored at 13 to 150C for six months.Thermal Processing:These include flash heat treatment, thermo stabilization and simultaneous coating.Flash heat treatment: was introduced by Romanoff and Romanoff (1944) based on the immersion of egg in boiling water for 5 seconds. This resulted in egg with superior storage characteristics at storage temperature of either 5oC or 21oC (41 to 70oF). Immersion for only 3 seconds in boiling water was effective in reducing bacterial spoilage in fresh eggs.Thermo stabilization: A quite different treatment for the preservation of shell eggs was reported by Funk in 1943. This involved immersion in hot water or oil for sufficient time to kill the embryo in fertile eggs and to stabilize the thick albumen. The time and temperature suggested by Funk was immersion in water and oil at 60oC (140oF) for 14 minutes along with simultaneous oil treatment and thermo stabilization complement each other in maintaining inner quality of egg. The problems of commercial application of thermo stabilization are 1) the coagulation temperature of egg white varies with the pH of the egg white. 2) temperature achieved by egg is influenced by egg size, starting temperature of egg, agitation of heating medium, 3) as well as time and temperature.

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Cold storage:For start period storage, fresh eggs should be 12.5-15.5oC (55-60°F) and 70-80% relative humidity. For long term storage the room temperature should be at 10oC (14±1°F) and relative humidity 80- 90%, as this relative humidity will sufficiently retard evaporation without danger of mould growth. Eggs can be oil treated prior to cold storage to enhance their keeping quality. The quality of the shell eggs can be maintained for 6 months in a cold storage.

A final consideration in the presentation of egg quality is the maintenance of flavor; eggs will pick up flavours from storage areas, such as onion, garlic, apples, oranges, decaying vegetable matter, oil, gasoline or organic solvent. Oil dipped eggs could be kept at 14oC and 90% RH, or 13oC and RH 85% or 20oC and RH 72% for 8 months, 60 days and 28 days respectively against 6 months, 30 days, and 7 days at corresponding storage temperatures of unoiled eggs.Pickling:

The eggs can be preserved by pickling also. It can be done with eggs of small size like that of quail eggs as it will allow proper penetration of pickling solution throughout the egg. The Central Avian Research Institute (CARI) has developed a technique for pickling of quail eggs.

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QUESTIONS:

1. What are the physico-chemical changes responsible for poor egg quality?

2. What are the different methods for preservation of eggs, write in detail.