eChapters

Livestock have the potential to be transformative; by enhancing food and nutrition security and providing the income to pay for education and for other needs, livestock can transform lives of many (Jimmy Smith et al., 2013). The projected growth of population is 9.6 billion in the year 2050 from the current population of 7.2billion (Gerber et al, FAO, 2013). The world demand for milk and meat in 2050 is expected to expand 58 and 73% respectively from their demand levels in 2010 (FAO, 2011). Nevertheless, the growth animal agriculture is not on par with the demand. Today, in a world of limited resources, in the face of climate change and a rising world population, a major issue is global food security (Augustine et al 2013). The key inferences of the latest approved summary for policymakers by the IPCC (2013) on climate change are 1). Warming of climate system is unequivocal and will continue beyond 2100. Global surface temperature change for the end of the 21st century is expected to exceed 1.5°C relative to 1850 to 1900 for almost all RCP scenarios 2). It is very likely that frequency of heat waves and heavy precipitation events have increased 3).

Climate change has become a global threat as its impact is evident on the Earth. In the coming decades,the severity of climate change is expected to aggravate the ecosystem. Due to its vulnerable ecosystem and geographical location, the North eastern region (NER)of India that is home to about 40 million people is considered as one of the most climate sensitive areas in the country. The NER is among India’s least developed region andscarce information is available on the impact of climate change in this region. However, initial scientific research and field observations confirm that the region is suffering from the impacts of climate change already. The region comprising 0.26 million km2area occupying 8% of nation’s territoryconsists of the states of Assam, Arunachal Pradesh, Manipur, Meghalaya, Mizoram, Nagaland, Tripura and Sikkim. These states consist of a part of the east Himalayan region, which extends eastwards from Arunachal Pradesh to the Darjeeling hills of West Bengal. The entire region is a part of Indo-Burma and Himalayan hotspots i.e. characterized by rich biodiversity, heavy precipitation and high seismicity.

One Health is defined as “the collaborative effort of multiple disciplines working locally, nationally, and globally to attain optimal health for people, animals and the environment.” The concept of ‘One Health’ dates back to the Greek physician Hippocrates (ca. 460 BCE–a.370) who in his text “On Airs, Waters and Places” stated:

Whoever wishes to investigate medicine properly, should proceed thus: in the first place to consider the seasons of the year, and what effects each of them produces, for they are not all alike, but differ much from themselves in regard to their changes.

The climatic changes and global warming may impact the economic viability of livestock production systems in a significant manner. The possible consequences of increased ambient temperature on the livestock include reduced feed intake, reduced weight gains, lower milk production and lower conception rates during summer periods. Though animals can, to some extent, adapt to higher temperatures with prolonged exposure, the production losses are likely to be exhibited in response to higher temperature events. However, potential direct and indirect impacts of climate change on livestock production have not yet been thoroughly explored. Changes in availability and quality of fodder have also been identified as one of the major impacts of climate changes leading to lowered productivity of livestock species. Climate change could also affect the distribution of vector-borne livestock diseases. These changes occur as a result of shifts in the geographical ranges of ticks, mosquitoes, flies and other vectors.

Over the past decades climate change and climate related disaster risks have become more important than ever. The effects of climate change are unprecedented today and thus pose serious risks for human wellbeing, livelihoods and life-supporting systems. They also present serious challenges to society, in addition, increased climate variability significantly undermine the socio-economic development and environment. The consequences of climatic change, such as increase in frequency and extent of droughts, floods, cyclones, mudslides and avalanches have impacts on all sectors of economy including water, agriculture, fisheries, health, forestry, transport, tourism and energy sectors. Amongst these sectors, the agricultural sector is one of the most vulnerable sectors to impacts of climate change, which can have multiplicative effects on other sectors, as well as the economy and overall human being. The projected climate change towards warming may affect not only the crop cultivation but also on agro-climatic conditions for growing pasture vegetation, forming of feed stocks in pastures and conditions for grazing livestock. Favourable conditions for grazing livestock are determined, on the one hand, by sufficient amount of forage in pastures and on the other, by the extreme weather conditions that restrict the use of these fodders.

Increase in ambient temperature, drought, rainfall, desert, feed and fodder scarcity, water scarcity and other climatic stresses are very common to tropical climatic conditions. The animals living in tropical climate have to undergo some modification for their survival under such extreme conditions. Interestingly, higher percentage of livestock is found in tropical and sub-tropical regions of the world. These areas are rich in animal resources. There are several descriptive and non-descriptive breeds of bovine distributed in different agro-climatic conditions of India. They possess several traits which make them adaptive to such climatic conditions. Identifying those traits and propagation of such traits is beneficial in near future in respect of climate change scenario. Climate change is the major concern for the improvement and sustainability of livestock under tropical climatic conditions. The rising of temperature and humidity is one of the major threats to animal’s productive performance that leads to great economic losses. Upadhyay et al. (2009) estimated 2% loss of milk production due to thermal stress in India. It has also been expected that 3.2 million tons reduction by 2020 and more than 15 million tons by 2050. The decline in milk production reported to be higher in crossbreds (0.63%) followed by buffaloes (0.5%) and indigenous cattle (0.4%) (Upadhyay et al., 2009). 

The modern commercial poultry production in India is barely 50 years old, although backyard poultry keeping dates back to pre-historic period. In between 1955 to 1965, some Christian Missionaries had imported White Leghorn, Rhode Island Red and White Rock breeds, to upgrade the local chicken, having very high disease resistance power; but highly broody. Later, hybrid broiler (Arbor Acres) and layer (Babcock) strains were brought to India in early seventies, to start modern poultry industry. Among the two, the layer industry took wings early and registered a spectacular growth rate between 1970 and 1985. The broiler industry came to existence five years later and showed 25 -100% annual growth rate initially and 10-20% growth rate subsequently; between 1975 – 2005. The growth indicators of poultry development in India are presented

The modern breeds of chicken have known to be descended from the wild jungle fowl. India, Nepal, Bangladesh, Myanmar, Thailand, Sri Lanka and Malaysia are the homeland to these jungle fowls. There are four known species of jungle fowl viz. Gallus gallus (Red jungle fowl), Gallus lafayetti (Ceylon jungle fowl), Gallus sonnerati (Grey jungle fowl) and Gallus varius (Java jungle fowl). The domestic breeds of chicken/fowl have originated from Gallus gallus.

The word indigenous, originates from the Latin work, indigena, implies that the individual and its ancestors originated from a specified country or continent. Presently, certain synonymous words used for indigenous chicken are: ‘native’, ‘local’ or ‘village chicken’. The indigenous fowls are well adapted to the local climate, need less input and produce tasty egg and meat at the least possible cost through scavenging. The birds require no scientific feeding, health care, housing and management and thus make the indigenous birds suitable for backyard poultry farming. Indigenous birds are normally handled by women, can significantly contribute to farmers’ livelihoods through increased food security and cash income. These breeds are self-propagating; contribute to poultry diversity and cultural heritage. Because of their local origin they are less prone to disease or predator attacks, and their cultural and sporting values secure additional income. The prices of egg and meat of local birds are 100- 150 percent higher than that of commercial counterpart. Some of these fowls are described in brief, as below.

Male Reproductive System

Male reproductive system (Fig. 15) consists of testes, epididymis, vas deferens and papillae.

Cocks have two ovoid creamy white testes, of which the left one is slightly larger than the right. Testes are located in the fore end of the kidneys in the abdominal cavity. Closely attached to the testes is short epididymis that continues as vas deferens which ends in the cloaca. The copulatory apparatus consists of two papillae and a rudimentary copulatory organ, the phallus which is located on the median ventral portion of one of the transverse folds of cloaca. Accessory reproductive organs like seminal vesicles, prostrate and Cowper’s glands are absent in the cocks. The phallus is small and has associated lymph glands that produce a fluid which is added to the semen.

The spermatozoa pass through the epididymis and are stored in the distal end of the vas deferens. The sperm after mating is stored in the folds in the oviduct of the hen to effect fertility up to six days. The spermatozoa of the cock have a long cylindrical head with a pointed acrosome, a short mid-piece and a long tail. Cocks produce about 0.5 -1 ml of whitish semen per ejaculate with a sperm concentration of 2- 4 billion.

A hen can produce eggs without mating by a cock. Such an egg is edible but infertile and will not hatch. If the hen is naturally or artificially inseminated with poultry semen, the spermatozoon unites with the ovum to form a fertile egg that will hatch after incubation. Unlike mammals, the embryo of birds grows independently within an enclosed hard structure called shell and thus, all nutrients required for embryonic development are contained in the egg. The yolk, albumen, shell membrane and shell protect the developing embryo apart from providing well balanced nutrients.

In modern poultry farming, successful management relies on accurate and complete daily record keeping. Some of the traits may influence the profit of farm, thereby affecting the economics of the farm than the other traits, and hence they are called economic traits. Economic traits can be defined as those traits which are economically important and improvement in these traits would increase the profit of the farm. These traits are generally assumed to be controlled by the genes at larger number of loci. Some of the economic traits in egg and meat type chickens are as follows:

Importance of Backyard Poultry Farming in India

Commercial chicken production in India has undergone a remarkable change in the last three decades. While India is among the top five chicken producing and top seven duck producing countries in the world, the gap between the demand and production is still alarming. Average per capita availability of eggs in big cities is 170 while it stands at 9 eggs per annum in the rural areas. Though the commercial poultry sector has made a stupendous progress over the years, the conventional free and backyard poultry farming remain neglected. Backyard poultry farming contributes around 11% to the national production while in certain states like U.P. around 60% of the poultry population is indigenous fowls reared under backyard system. The backyard sector contributed to 23 per cent of the total egg production in 2005-06.

Commercial chicken production is capital intensive and is generally concentrated in and around urban areas. There is a wide disparity in consumption of the poultry products between urban and rural population. Around 75% of country’s population living in the rural areas has limited access to the protein rich poultry products. Protein deficiency is quite common in the diets of rural people. Adoption of rural poultry farming may ameliorate the high incidence of protein hunger in growing children and pregnant women.

It has been seen that the commercial birds have poor immunity against common poultry diseases. As production is inversely proportional to the viability traits, the nutrients absorbed are mostly diverted for growth in commercial chicken. On the other hand, indigenous birds reared in rural areas are resistant to many diseases and pests. Unlike the local breeds maintained in villages, the commercial breeds require high level of input pertaining to feed and health care to maintain production and check mortality.

Poultry industry in India has registered a phenomenal growth during the last four decades making it one among the world leaders in poultry production. The development of organized poultry has in fact masked the contribution of backyard poultry or house-hold poultry of rural sector. Backyard poultry production in India is characterized by small flock size consisting of 5-10 predominantly non-descript birds maintained in extensive system under zero input conditions but fetch the owners much needed animal protein and supplementary income. Importance of backyard poultry is well recognized by Government of India and special programmes are formulated for its promotion.

Non-descript Chicken

Maintaining small flocks of local non-descript fowls under free range condition by landless poor, small and marginal farmers are a common sight in rural areas. These birds are very popular due to their adaptability to local agro climatic conditions and management practices with prominent brooding behaviour and mothering ability. But these birds are small in size, poor layers (40-50 eggs/ annum), with small clutch size and intense brooding behavior, thus making them not suitable for commercial exploitation.

Mixed farming exists in many forms depending on external and internal factors. External factors are weather patterns, market prices, technological developments, etc. Internal factors relate to local soil characteristics, composition of the family and farmers’ ingenuity. Farmers can decide to opt for mixed enterprises when they want to save resources by interchanging them on the farm - because these permit wider crop rotations and thus reduce dependence on chemicals, because they consider mixed systems closer to nature, or because they allow diversification for better risk management. There is wide variation in mixed systems. Even pastoralists practice a form of mixed farming since their livelihood depends on the management of different feed resources and animal species. Mixed farms are systems that consist of different parts, which together should act as a whole. They thus need to be studied in their entirety and not as separate parts in order to understand the system and the factors that drive farmers and influence their decisions. It may be the most important principle to achieve increased production in mixed systems, together with the awareness that crops and animals have multiple functions.

Brooding and Rearing Practices Used for Chicken

What is Brooding?

Rearing of young ones immediately after hatching for at least 2-3 weeks, either by natural means or by artificial method is called brooding. Brooding is done by two ways i.e., Natural or Artificial ways.

Natural Brooding

In the natural method a desi fowl which acts both as incubator and brooder is used to raise only a small number of chicks. She sits on eggs (chicken) for 21 days to produce chicks from fertile eggs and broods thereafter.

Among various animal husbandry enterprises, poultry production has emerged as number one position and attained industrial status in many countries, including India.

This tremendous growth in poultry production is due to the following reasons:

There is no religious taboo towards poultry and poultry products.

Egg is the most nutritious, natural, unadulterated and easily digestible food with the highest biological value.

Eggs can be consumed by all age groups and economic classes, since it is the cheapest among all the nutritious natural foods on the earth.

Among various meats, poultry meat has the highest protein, lowest fat and cholesterol content.

Poultry is the best converter of feed into meat and eggs. A hen needs only 1.5 kg feed to produce 1 dozen eggs. Similarly a broiler needs less than 2 kg of feed to produce one kg broiler meat whereas other species need more than 3 kg of feed to produce 1kg of meat.

Poultry has the shortest generation interval among various livestocks.

Poultry meat and eggs have high nutritive value. Egg is used as a standard for measuring the quality of other food proteins. It is a well balanced source of nutrients. Similarly poultry meat is easily digestible, high in protein and low in fat content. It contains all the essential amino acids. Though the poultry meat and egg production have tremendously increased in India during last few decades however due to lack of organized marketing channels poultry producers are not getting reasonable returns. Indian broiler and egg markets are in a disorganized state. In last few decades various efforts have been made so as to organize and co-ordinate marketing channel of poultry meat and eggs. Through these efforts producers are also benefited but only in some particular areas. Therefore, there is need to expand it further covering the country.

What is Marketing?

Marketing may be defined as exchange of a produce for an agreed sum of money. It is a commercial process involved in promoting, selling and distributing a product. In simple words marketing is finding out what customers want and supplying it at a profit. Marketing is a business in terms of customer needs and their satisfaction. As per P. Taylor, marketing is not simply providing products or services; it is essentially about providing changing benefits to the changing needs and demands of the customer.

Selection of site for a poultry farm: The following points should be considered while selecting site or location for a poultry farm.

The farm should be located at an elevated area with proper facilities for drainage.

To protect the farm against strong wind, tall trees may be planted surrounding the farm complex.

The farm should be located not too far from city to bring in and take out materials.

The commercial farm should be located near to marketing centres.

The breeder farm should be located in an isolated area away from commercial farm to ensure biosecurity.

The farm should have an easy access to connecting roads.

The site should have provision of electricity.

The desirable soil type for a poultry farm is loamy or sandy loam.

There should be provision of abundant potable water at the site. The water should be tested for various impurities like total solids, microbiological contamination, high percentage of salts of Na, K and Chlorine, nitrite, nitrate etc. Total bacterial count and Coliform count should be 0/ml.

Organic Farming

The FAO/WHO Codex Alimentarius Commission defines organic farming as “a unique production management system which promotes and enhances agro- ecosystem health, including biodiversity, biological cycles and soil biological activity, and this is accomplished by using on-farm agronomic, biological and mechanical methods in exclusion of all synthetic off-farm inputs”. It is a certification of a production system as opposed to the certification of a product. For a product to be certified organic, all operators in the product chain, including farmers, processors, manufacturers, exporters, importers, wholesalers and retailers must be certified organic. The establishment of organic animal/poultry husbandry requires a specific period called as “conversion period”. This period is the time taken between the start of the organic management on farm and certification of livestock farm and its product. Changing from conventional to organic management system for livestock enterprises requires a careful and gradual approach. It is learnt that global organic product has increased 20% annually over the past 10 years. Though Australia, European Union and USA are leading organic producers, a recent study indicated that developing countries including India are also adopting the system and marching ahead.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

Grasshoppers are highly voracious herbivores having the world wide distribution. It is particularly found across — Asia, Africa, Europe and Australia. In India it may be seen in abundance during monsoon season. This pest is of International importance and the following three species are commonly found in India of which desert grasshopper is predominant all over the country.

The integument is composed of the cuticle and under lying epidermal cells that secrete the cuticle. The integument is a complex vulnerable organ system of diverse function. The insect outer body covering is called integument. The integument is a central subject intimately related to a variety of applied - Problems such as the mode of action, insecticides, ecology, cuticle and endocrine glands present in the body of insects. The insect integument consists of 3 parts and plays crucial role in locomotion, breathing and respiration, feeding, excretion, protection from desication behaviour of insect.

1. Epidermis Layers
2. Basement Layers
3. Cuticle Membrane

ORIGIN OF INSECT

Entomology is a branch of zoology which deals with insects. In this branch we study the insect origin and evolution of insect and their diversity and classification and other parts of insect body. Insects belong to the class insecta in the phylum arthropoda, the largest group in the animal kingdom. All arthropods are characterised by having segmented body, claws, chitinous exoskeleton, ventral nervous system and dorsal heart. The class insecta is generally considered to have evolved from myriapod of some sort during the Devonian period. Based on different mandibles and mandibular movement concluded that insects are not direct insect group myriapods the mouth is located between the prostomium and the first body segment and the anus open in the periproct.
The first great step was the development of a pair of ventral appendage. Insect legs on each body segments and locomotion, parallel to this an improvement in the sense organs of the head occured eyes and Antenna were the ultimate result this level of organisation is met in onychophora. A series of diagramms is helpful in a very simplified way in visualising the hypothtical origin of insects.

The digestive system of insects comprises of two main sub-parts, one is the alimentary tract or also known as the digestive tract and the associated digestive glands. These digestive glands may be associated directly or indirectly such as, salivary glands, gastric, caeca (directly) and Malpighian tubules (indirect). If we have to describe an insect and its anatomy, or its histology, it is based on the orthopteroid plan, which is mostly shown by grasshoppers, crickets, and locusts, because their plan shows and describes the basic, primitive design from which other groups of insects have enolved and showed modifications and specialization. We can say that this orthoptera insect shows the general anatomical and histological features of a generalised insect.Today, we see that insects have invaded and adapted in almost all types of habitats and the major reason for their biological success is their ability to show digestion, utilization and their ability to eat an extremely vast diversity of food. It is due to this abilityof extremizm in food diversity that insects have undergone many specializations and modifications of the alimentary canal. What modifications a species of insects undergoes, depends upon the type of insects, depends upon the type of food it consumes. The diversity is also seen in the way of obtaining, storing, processing and absorbing the food. These differences may be structural or functional or both. It is not necessary that these differences must be present in different species only, those may be shown by different life stages of a single insect, by two sexes of a single species, etc. e.g., the difference between the mouths parts of mosquito species.

Insects, belonging to the phyllum-arthropoda, have an open circulatory system. An open circulatory system is that in which blood bathes the organs rather internal organs directly in the haemocoel, the coelom of the insects, which actually is not a true coelom. Almost entire haemocoel of insects is formed from the epineural sinus. The haemocoel is divided into the perineural sinus and perivisceral sinus by the dorsal and ventral diaphragm respectively. The characteristic of insects is the presence of dorsal vessel, which comprises of anterior aorta and a posterior heart and is the only conducting tube present in insects. The blood of insects mostly does not perform gaseous exchange, therefore it does not contain haemoglobin, and blood in insects is called the haemolymph, which is red-coloured. So in order to study the circulatory system of insects, the major focus must be on the dorsal vessel, which has been described as follows, along with its accessory structures.

Excretory system of an organism maintains its homeostasis i.e., a constant internal environment. Here in insects, the blood is haemolymph therefore it determines the excretion of an insect’s body. Excretion also eliminates the nitrogenous wastes and maintains the salt- water balance and also regulates the uniformily of haemolymph. The characteristic feature of insects is the presence of malpighian tubules to eliminate the metabolic wastes, whereas rectum walls carry out the function of reabsorption of salt and water. A minimum amount of water is excreted with nitrogen waste in order to conserve the water in body.

Insects show sexual Dimorphism i.e., the sexes are usually separate and are dioecious. Male reproductive system produces sperms, stores them and delivers them i.e., spermatozoa. It also produces the seminal fluid, which provides a suitable environment to the sperms and nourishes them. Male reproductive system also situmilates are the female for oviposition. The female reproductive system produces and stores eggs provide nutrition to them for embryonic development, recieves and stores the sperms, is a site of fertilization. Female reproductive system also deposite eggs and may provide additional protection to the embryos. The reproductive system of both male and female insect’s bearis a gononpore, which is an opening of a pair of gonads. Both the gonads open into the gonopore by a median duct. For the secondry sexual purposes, e.g., formation of spermatophore and egg-case or ootheca, some accessory glands are associated with the reproductive system.

The respiratory system or tracheal system is involved in gaseous exchange in the insect with the environment. In this system there is a system of internal tubes, the tracheae that directly transport the oxygen to the parts of the body. Therefore, it does not use the circulatory system as the vehicle for gaseous exchange. The trachae open outside through segmental pores called spiracles having some system of closing and opening. Except proturans and some collembolans all insects possess tracheal system for respiration. These insects live in moist habitats where gaseous exchange takes place directly with the environment via the integument.

In insects nervous system is highly developed and serves to coordinate the activities of its various systems. Units of this system are known as neurons. Which carry information in the form of electrical impulses from external and internal sensilla (Sensory cells) to appropriate effectors e.g., glands, muscles and glail cells. Nervous system of insects may be divided into three parts.

1. Central nervous system
2. Sympathetic or visceral nervous system
3. Peripheral nervous system.

Exocrine Glands Types: Exocrine glands are generally of ectodermal origin and are widely scattered over the insect. Exocrine glands release their secreations through ducts into the lumen of various internal organs. Example: Accessory reproductive glands, salivary gland, silk gland. Gland is mainly composed of secretory epithelial cells. These are simple unicellular, bicellular, multicellular, complex multicellular (compound glands). These glands are ectodermal in origin and are secreated over the insect body.

Examples. Wax glands, lac glands, cephalic glands, poison glands.

1. Glands pouring (secreting structural materials). Some insects secrete substances that are used in building their houses (beehive) as protecting them (lac or cocoon).

The term ecology was first of all proposed by zoologist H. Pietir in 1865. It was derived from the Greek word ecologic means oikos = living place and logos = study and some definitions of ecology presented below:

1. According to Ernst Haeckel, 1869 “The total relations of the animal to both its organic and inorganic environment is called as ecology”.
2. E. Warming 1895 “Ecology is the study of animals and plants in relation to their environment”.
3. According to Odum 1963 “Study of structures and functions of nature is defined as ecology”.
4. Krebs 1985 says that the “Ecology is the scientific study of interaction that determine the distribution and abundance of organisms”.

The life of insects is dependent on the adaptability of the environment, if the environment is unfavourable then the insect population ceases and vice-versa. This insect move one place to another to get the favourable environment so that they can pull on their life activities properly. There is a deep relationship between the living community and non-living environment. Both are affecting each other greatly. This inter-relationship between living community and non-living environment is called as ecosystem. The term ecosystem was first used by A.G. Tansley as early as 1935 and he defined, “Ecosystem is the system of resulting from the interaction of all the living and non-living factors of the environment”.

Many insect can be observed at any hour of the day. This is proper understanding of the taxonomy and biology. The insect collection, storage and preservation are useful technique of their culture. The best period for collection is from early spring to late rainfall and the best time of the collection of most of the species is during the daytime. The insect are polyphagous and therefore, plants provide one of the best collecting places. Insect can be picked, swept off the plant with the help of a net. Different species feed on different kinds of plant, one should therefore, examine all sorts of plant, flowers weed shrubs and trees. Few insect are only found in the stem, bark, wood, fruit or roots etc. Some species can be found in the leaf mud and litter on the surface of the soil, particularly in woods or areas where the vegetation is dense, others can be found under stones bark etc. other house hold insects may be observed feeding on clothing, furniture, grain, food and other parts of Plant and House and some are aquatic insects.