eChapters

Accurate early diagnosis of pregnancy is essential for successful breeding programme.

Ability is required for successful practice.

Skill is to be developed to indicate the duration within weeks in early and months in late pregnancy.

RECTAL EXAMINATION

It provides practically all the information required.

It is the simplest, accurate and reliable method with no cost involved.

Things Required

A full arm rubber sleeve with attached glove or disposable plastic glove.
A rubber or plastic apron.
Non-irritant soap or lubricant.

Principles of Incubation

Incubation is a process by which the embryo within egg develops into a fully formed chick capable of breaking free from the shell. Basically, when a hen incubates an egg, it means she is on the egg in order to keep it warm for a certain period of time, 21 days for chicken, until the chick embryo has fully formed and is ready to hatch. The incubation period in other species is given in Table 41. The following factors affect the incubation on egg

1. Temperature

Incubator temperature should be maintained between 99 and 100 oF. The acceptable range is 97 to 102 ^oF. Overheating is more critical than under heating. An incubator should be operated in a location free from drafts and direct sunlight. Temperature is probably the most important single factor influencing the development of the embryo. A higher temperature will advance the hatch and a lower temperature will delay hatch. Younger embryos are especially susceptible to high temperatures because the upper lethal limit is very close to the optimum incubating temperature. High temperature will cause the embryonic membranes to dry out too soon. Chicks that hatch may have an unsteady gait.

Artificial insemination (AI) is the deposition of the semen or male germ cells (spermatozoa) in the female genital tract by artificial means (instruments). Artificial insemination includes collection of semen from the male, preservation, handling and deposition into the female reproductive tract hygienically replacing natural mating by a male. In India this technique is gaining momentum in chickens due to improved animal husbandry practices and economic considerations, initiated by IVRI, Izatnagar and JNKVV, Jabalpur. In many parts of the world, turkey, ducks, goose and guinea fowl are bred solely by AI. Chicken species are endowed with the behaviour and capacity of each male to mate several females and also 25 to 40 times a day. Further, the process of ovulation in birds is almost daily and stimulated by intensity and duration of light.

In modern poultry managemental practices of using cages, environmentally controlled houses and breeding and hybridization techniques employed for developing highly economical chickens, selection for faster growth and heavy body weight in broilers, which has led to loss of fertility and hatchability and use of dwarf female parents in broiler industry have demanded the use of AI in poultry.

Breeder management includes pure line management, parent stock management, and grandparent stock management depending on the context. Except for small variations in management among these stocks basics are common within layer breeder stocks and broiler breeder stocks. The main objective of the breeder management is to produce more fertile eggs per pullet and increasing the hatchability by hygienic handling of these fertile eggs.

Location of the breeder farm

Location of the breeder farm should be away from commercial poultry farms in order to prevent the spread of diseases between the flocks. However, they must be in close vicinity of the city/town to have a good transport facility and other amenities such as water, electricity and availability of labour.

Chicken’s eggs have been used as a food item by human beings since antiquity. The egg is composed largely of the proteins out of the three most important dietary essentials (proteins, fats and carbohydrates). The egg proteins are highly digestible and remarkably complete, containing the most important essential amino acids. The amino acid profile of egg is similar to the ideal balance of amino acids needed by humans. It also supplies various minerals, some in significant amounts, and contains a range of vitamins. The nutritive excellence of the egg enhances the value of any food in which it is incorporated. Meeting consumer demands is a constant challenge for the poultry industry. Present day consumers desire somewhat distinct products with respect to safety, healthfulness, freshness, taste, color, etc. To remain competent, various companies have developed several designer and specialty eggs which have appeared in supermarkets.

Common Poultry Diseases

Infectious diseases

Bacteria

Commonly known as “germs”, bacteria are very small living microorganisms. Only a few bacteria cause diseases. In birds these include Salmonella, Clostridia, Pasteurella, Vibrio, Staphylococci, Streptococci, Mycoplasma, Hemophilus, and Mycobacterium etc.

Digestive System and Digestion in Chicken

Studies on structure and functions of digestive system of chicken play important role for their nutrition and feeding. Functions of each part are given below (Fig 35):

Mouth: Birds feed through the beak. The horny upper and lower mandibles form the beak. Lips, teeth, cheek and soft palate are absent. The dagger-like tongue helps to force the feed into the esophagus. Chicken has 24 taste buds with high sense of taste. Absence of teeth makes the particle size of the feed important.

Esophagus (Gullet): It is made of loose fibrous tissue and serves as a tube to pass the food from mouth to crop. This is relatively long because of the long neck of the fowl.

Crop: (Ingluvius): It is a pouch like structure of esophagus to store, moisten and soften the food. It gives information about the feeding habits of the fowl.

Proventriculus (Glandular stomach or True stomach): It is an enlarged glandular ovoid structure of the esophagus connected to gizzard. It secretes pepsin and Hydrochloric acid.

Gizzard (Muscular stomach): Disc shaped muscular organ with two pairs of strong thick muscles and lined internally with a thick horny epithelial covering called the Koilin layer. Coarse materials are ground well by its powerful contractions with the support of the grit that birds consume.

For maximization of productivity in any kind of poultry venture the knowledge on the behaviour of birds and its application play very significant role. Behaviour is the reaction of the whole organism to certain stimuli, or the manner in which it interacts to its environment. Behavioural patterns are not inherited as such, but develop through the process of growth and get differentiated under the influence of genetic and environmental factors. Primary function of behaviour is to enable the bird to adjust itself to some changes in condition, whether external or internal. Most animals have a behavioural pattern which can be tried out in a given situation and in this way they learn to apply one or the other according to that which produces the best adjustment.

Biosecurity means protection against infectious biological agents. These agents include bacteria, viruses, protozoa, fungi, parasites, and any other agents capable of introducing infectious diseases into a poultry flock. Biosecurity therefore means maintaining a flock, poultry house or premises in such a way that infectious agents do not have a chance to enter to cause diseases. The biosecurity may be categorized into three: Conceptual biosecurity, Structural biosecurity and operational Biosecurity.

Importance of Biosecurity

In modern poultry production, birds are reared under intensive system where large numbers are concentrated in small area. As a result, when an infectious agent enters a poultry house, there is probability for widespread dissemination if it is not contained. Besides, the broiler and egg industry of today is under increasing consumer and regulatory pressures to guarantee food safety and meet export requirements. As a result, broiler and layer operations around the world require the supply of breeding stock free of salmonellas specific to avian species (such as S. pullorum and S. gallinarum) and those that could cause outbreaks of human food-borne illness. Inadequate biosecurity can contribute to wide epidemics of highly pathogenic or exotic diseases. An infection by a virulent organism within a facility can be devastating, reducing without overt signs of disease. Once contaminated with pathogens, poultry facilities are extremely difficult and expensive to clean, sanitize and disinfect. Prevention of disease is always less expensive than treatment. The cost of implementing biosecurity system is smaller when compared to financial profit that can be made from production. Good biosecurity is therefore vital requirement in the best possible control of disease.

Water is the most important and abundantly required nutrient for poultry. A continuous supply of clean, fresh and wholesome potable water is essential for poultry. Poultry rearing is becoming more and more intensive with which the chances of the infectious diseases being sustained in the different flocks also increase. Consequently, the need for effective disease control measures to be adopted also gains further importance.

Most often, poultry farmers get alarmed only when the mortality level or death rate in a farm is high. However, even the existence of disease at a sub-clinical level may hinder the performance of the birds, in terms of body weight or egg number; such economic losses, sometimes relatively less and unnoticed, may mean the difference between success or failure in the poultry business. Treatment of a sick flock after the onset of any disease becomes costlier and more frequently impracticable. The recovered birds may not regain their production to original levels and may also continue as source of infection to other healthy birds. Hence, the adage ‘prevention is better than cure’ applies more to poultry industry than any other field.

Vices of poultry are undesirable behavioural pattern manifested by the bird in the flock and spreads fast among the members resulting in financial losses.

Types of Vices

Pecking

Cannibalism

Egg eating

Any deviation from optimum state could be referred as stress. Every living creature has to pass through one or the other type of stresses in life. Most of the farm animals including poultry suffer from various types of stresses. These include due to:

Adverse environment

Managemental practices

Diseases

Nutritional deficiency

Transportation etc.

Management of the poultry house environment forms an essential aspect towards maximizing production performance. Generally, proper maintenance of poultry litter is seldom given emphasis. The condition of litter significantly influences bird’s performance and ultimately affects the economy for rearing. The litter is defined as the bedding materials of around 5-6 cm height consisting of locally available materials like rice husk, peanut hull, wood shavings, paper shreds, sawdust or groundnut hulls. These materials can be used alone or in combination to rear the birds on floor under deep litter system of management. The excreta, feathers, spilled feed and water are mixed with bedding material, get further decomposed due to heat and bacterial action resulting in built-up-litter towards the end of rearing.

In 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 and further processed products. The Directorate of Extension, Ministry of Agriculture, Govt. of India annually conducts livestock and poultry shows in various parts of the country in collaboration of state governments. Besides, state Agricultural/ Veterinary Universities or other institutions also conduct such shows. In these shows judging contests are carried out mostly for the undergraduate students by using a score card to grade birds either for production characters or breed characters. The winners are awarded trophies and cash prizes. The birds meant for judging are kept in individual cages and the participants are requested to score under various sub-headings and to finally rank the bird. Any deviation from “ideal” or “perfection” (as described by the American Standard of Perfection or the British Poultry Standards) but not serious enough to constitute a disqualifications in the show room is considered to be a defect. Serious defects are regarded as disqualifications and will bar a bird from winning any prize. Both layers and broilers can be physically evaluated for their performance rating.

Care and Management of Commercial Growers (09-20 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 waterers 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 cm² (1.4 ft²) 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 waterer of 36 cm and 8 cm depth of 6 lit. 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.

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, iii) 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.

Housing constitutes the second largest component of cost of poultry production. An ideally located and well planned poultry farm is an essential requirement for efficient egg and meat production. Poultry housing normally serves the following major functions:

Provides shelter and protection to the birds

Provides comfort to the birds.

Helps in organization of large flock into a manageable unit.

Project for Rural People on Chicken

For rural people Desi (indigenous) chicken plays an important role. Family poultry farming is a part and parcel of a typical rural household in India touching social, cultural and economic aspects. People residing in rural areas primarily maintain their indigenous chicken under backyard farming. With the same management system the rural people can rear improved varieties of chicken instead of their traditional counterpart. The improved varieties being Giriraja, Vanaraja, Kuroiler, Gramapriya, Gramalaxmi, Swarnadhara, Krishna J etc. A model project on improved chicken is given herewith:

A unit consisting of 100 number Vanaraja or Giriraja is economical and remunerative to the farmers whose family labour will be utilized for rearing these chickens. Initially, the farmer will buy about 225 straight-run day- old chicks. The males will be sold at 20 weeks of age. The females will be maintained for 1.5 years. In order to have continuous operation, next batch of 225 chicks have to be procured 6 months before disposal of the old batch. Birds will collect their feed through foraging or scavenging in the field. Supplementary feeding will be provided to meet their requirements.

Conservation Biology emerged as the scientific study of the nature and status of Earth’s biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction. Biodiversity itself has a wider meaning unifying and taking into account species, within species breeds/ varieties, ecosystem, genetic and molecular diversity.

Need for Conservation

The progenitor of modern-day chicken has been the Red Jungle Fowl and over the years breeds have been developed slowly for commercial purpose as layers and broilers. However we still have lot of indigenous birds which cannot be defined in either category.

Breeding capabilities Vs biodiversity erosion: Presently only about 3-4 poultry breeding companies provide meat stocks for farms around the world. A similar number of companies supply birds for commercial egg production. As a result modern animal industry now uses only a few breeds of any species. Of the many breeds once commonly seen on farms, many have declined sharply in numbers and others have disappeared almost completely.

Productivity Vs Conservation: On one hand, to increase productivity we want certain natural characters to be eliminated and on the other we talk of conserving the indigenous varieties, which sounds contradictory.