External Body conformation parts of chicken.pptx

Morphology
 Birds have no teeth and lips
 Beak is used for prehension purpose i.e., eating and drinking as well as protection and self defence
 No urinary bladder
 They can fly and some can swim & float
 No sweat glands
 The body of the fowl is profusely covered with feathers, such as the body feathers, flight feathers, tail feathers and sickle feathers.
 Filoplumes – hair like structures present at the root of feathers.
 Scales – rough projections of skin
Function of feathers and scales is to maintain the body temperature and also protects against abrasions and bruises.
 The domestic fowl resorts to flight only occasionally.
 Head carries a horny beak, nostrils, a pair of eyes, ears and the comb & wattles.
 The comb is fleshy, large and brightly coloured in males. There are many types of comb patterns in fowls. Among these, single comb, rose comb, pea comb patterns are present in most of the present-day breeds
Function of comb and wattles is regulating body temperature
 No diaphragm to inflate and deflate the lungs to aid in respiration
 Instead, they have air sacs and some bones are hollow and are called as pneumatic bones to aid respiration during flight.
 Gaseous exchange occurs in lungs whereas airsacs functions as organs to move the air in and out of the body.
 The body is supported by two limbs, which end in toes.
 The other pair of limbs of the tetrapod construction is modified to form the wings.
 The body is divided into head, neck, trunk and tail.
 The cloaca is situated behind the supporting limbs usually covered by tail feathers. Waste and metabolites from digestive and urinary tract are excreted from the single orifice
 Likewise, there are 3 types of body shapes among the different breeds of fowl, which is a feature related to the performance of the fowl. Good egg layers have triangular body, rectangular body for dual-purpose and round body for meat purpose.
Skeletal system
The skeleton serves as a framework for the body, for the attachment of muscles and protects vital organs.
Like that of other birds, the skeleton of the domestic fowl is very light in weight.
Head is very small and the bones are reduced and hollow.
Vertebrae Man / bovines Domestic fowl
Cervical 7 14 very high mobility and flexibility------maintenance of neck and head movement
Thoracic 12 7 fused bones ---connected to sternum & ribs to form ribcage, overlapping flaps from the ribs are called uncinate processes
Lumbar 9 fused bones
Sacral 6 fused bones and also fused with caudal bones to form synsacrum
Caudal 4 bones fused together called as pygostyle.

The cervical vertebrae support the neck and they are arranged in such a way that there is enough room for the fine movement of the head and neck in all directions for eating, care of plumage, defence and other purposes.
The backbone shows much fusion of vertebrae. Ribs are seven paired, and they are joined ventrally to the sternum and dorsally to the vertebral column.

1. BODY PARTS OF CHICKEN Prepared by Dr. Harshini Alapati (M.V.Sc Poultry science) Contractual Teaching Faculty Dept of LFC Veterinary College, Hassan KVAFSU, Karnataka

2. Modern breeds of chicken are descended from wild jungle fowl – Red jungle fowl ( Gallus gallus ) Taxonomical Classification of Fowl: Kingdom - Animalia Sub-kingdom - Metazoa (bodies consisting of specialized cells) Phylum - Chordata (axial skeleton with notochord) Sub-phylum - Vertebra (well developed brain and axial skeleton) Class - Aves (feathered, warm blooded vertebra with 4-chambered heart) Sub-class - Neornithes (without teeth) Super order – Carinatae (Keel like breast bone); Ratitae (Raft like breast bone – Ostrich, Emu, Rhea, Cassowary & Kiwi) Order - Galliformes (bird with beak, short wings, legs and toes adapted for running and scratching-----includes Jungle fowl, guinea fowl, turkey, peafowl and pheasant) Sub order – Galli (Fowl and game birds) Family - Phasianidae ; Sub family - Phasianinae Genus - Gallus (cock like bird) Species - d omesticus (breeding under domestic condition). The domestic fowl is called Gallus gallus domesticus .

3. Order Anseriformes (Duck, Gesse, Swan) Galliformes (game birds) Family Anatidae Phasianidae Genus Anas Carina Anser Gallus Coturnix Meleagris Numida Phasians Species platyrhynchus moschata anser gallus coturnix gallapavo meleagris colchinus

4. Birds have no teeth and lips Beak is used for prehension purpose i.e., eating and drinking as well as protection and self defence No urinary bladder They can fly and some can swim & float No sweat glands The body of the fowl is profusely covered with feathers, such as the body feathers, flight feathers, tail feathers and sickle feathers. Filoplumes – hair like structures present at the root of feathers. Scales – rough projections of skin Function of feathers and scales is to maintain the body temperature and also protects against abrasions and bruises. Morphology of chicken

5. The domestic fowl resorts to flight only occasionally. Head carries a horny beak, nostrils, a pair of eyes, ears and the comb & wattles. The comb is fleshy, large and brightly coloured in males. There are many types of comb patterns in fowls. Among these, single comb, rose comb, pea comb patterns are present in most of the present-day breeds Function of comb and wattles is regulating body temperature No diaphragm to inflate and deflate the lungs to aid in respiration Instead, they have air sacs and some bones are hollow and are called as pneumatic bones to aid respiration during flight. Gaseous exchange occurs in lungs whereas airsacs functions as organs to move the air in and out of the body.

6. Parts of head

7. Types of combs

8. The body is supported by two limbs, which end in toes. The other pair of limbs of the tetrapod construction is modified to form the wings. The body is divided into head, neck, trunk and tail. The cloaca is situated behind the supporting limbs usually covered by tail feathers. Waste and metabolites from digestive and urinary tract are excreted from the single orifice The skeleton serves as a framework for the body, for the attachment of muscles and protects vital organs. Like that of other birds, the skeleton of the domestic fowl is very light in weight. Head is very small and the bones are reduced and hollow.

9. Vertebrae Man / bovines Domestic fowl Cervical 7 14 very high mobility and flexibility------maintenance of neck and head movement Thoracic 12 /13 7 fused bones ---connected to ribs to form ribcage, overlapping flaps from the ribs are called uncinate processes Lumbar  9/7 9 fused bones Sacral  6/5 6 fused bones and also fused with caudal bones to form synsacrum Caudal  4/18-20 4 bones fused together called as pygostyle.

10. Parts of hind limb DIGIT CLAW

11. The pectoral girdle consists of scapula, coracoids and clavicles. Clavicles are fused together at their base called as furcula or wish bone providing a flexible attachment site for musculature The bones of the forelimbs are modified to support the wings. Humerus, radius and ulna, metacarpus and phalanges. Hindlimbs are long and adapted for walking and perching. The tibia or ‘drumstick’ is the largest bone of the limb. Femur, tibiofibular, tarsometatarsus, (3digits i.e., 2 nd , 3 rd 4 th ) phalanges 1 st digit is rudimentary and called as spur

12. Skin is composed of three layers of cells 1. Epidermis – outermost layer consists of 3 separate layer of cells 2. Dermis or corium 3. Hypodermis – innermost layer Structure The skin is mainly composed of two different tissues: Connective tissue of the dermis and hypodermis where the cells are widely spaced. Cellular stratified epithelium of the epidermis, which make up the horny outer layer of the skin and forms the feathers. D ifferent types of skin contains collagen ,  elastin  and  keratin in varied amounts.

13. EPIDERMIS Stratum corneum - The flattened, horny cell layer. Stratum spinosum - The transitional layer. Cells of epidermis transformed into the hard, and transferred the outermost layer. Stratum germinativum - The columnar cell layer . germinative layer where the cells of the epidermis are formed.

14. Skin surface cells are replaced continuously through life by mitosis in the epidermal germinative layer. As an outer or surface layer wears away or lost, the cell layer beneath replaces it. The tissue lost in this way forms part of the scurf or dander that provides site for colonization of external parasites such as lice and a place for the survival of disease causing viruses such as Marek’s Disease. Almost all of the activity of the epidermis is devoted to keratinisation that involves two processes: The synthesis or manufacture of the very durable fibrous protein, keratin that gives the skin surface its strength and resistance to normal wear and tear. The death of the cell – the final stages of keratinization occurs in the transitional layer of the epidermis. As the cells reach the stage where they become part of the horny cell layer.

15. Dermis & Hypodermis The dermis is relatively thin and shows a uniform, microscopic structure. The main component of the dermis is collagen with a small amount of elastin. The hypodermis contains fewer cells and is more loosely arranged than the dermis. Fat is stored here in special adipose cells. Air spaces found in the hypodermis connect with air sacs of the respiratory system to enhance the ability to fly.

16. The skin has many nerve endings located in it. These are mainly located in the outer layers of the dermis and provide good protection from potentially harmful situations by making the bird aware of their presence. The dermis is also quite well supplied with blood vessels that do not reach into the epidermis. Nutrients, respiratory gases, hormones and other compounds pass by diffusion into the live inner cells of the epidermis.

17. The fowl’s skin is divided into a number of separate areas where the skin has been modified to some extent to be able to carry out special functions. These areas are: The feathered skin. The scale covered skin on the lower legs and feet. The hard, horny areas of the beak and toe nails. The pad of the foot (or plantar). The skin of the comb and wattles. The feathered skin is also divided into a number of special areas where they grow are called  pterylae  and the areas where they do not grow are called  apteria .

18. Skin of t he Feathered Areas The skin is usually covered by the feathers is therefore normally protected and hence is thinner. Over the wings and thighs, the skin is more closely joined to underlying tissue than over the rest of the body. The epidermis is about 12 cells thick with the horny outer layer being about 5 cells, the transitional layer being about two and the inner, germinative layer being about 4-6 cells. Skin of t he Legs And Feet The lower legs, including the upper sides of the toes, are covered by skin carrying scales attached to the epidermis. Scales are very rich in keratin B reeds with feathered legs, feathers grow out of the margins of the scales. The scales are considered to be descended from the bird’s reptilian ancestors.

19. The Skin of t he Foot Pad Or Planter region The skin beneath the toes and the foot is specialised to withstand compression caused by the weight of the bird when standing and abrasion caused when the foot comes in contact with rough surfaces as the bird moves about. The skin of this area is quite thick but retains a high degree of flexibility. The Skin of the Wattles And Comb Comb & wattles- These are epidermal appendages on the head and neck. They develop as a result of the production of hormones by the sex organs of the male and female when these are functional. The very rich supply of blood vessels of these appendages is the cause of the bright red colour.

20. The Skin of t he Beak and toe nails The beak is composed of two parts: The internal skeleton of bone A closely attached layer of highly keratinised skin over the bony skeleton The epidermis of the beak develops a thick, horny layer (called  rhampotheca ) made of sheets of flattened cells firmly attached to each other. The strength of the beak keratin is partly due to its special make-up. The hard egg tooth that a hatching chicken uses to break out of the shell is made of strongly calcified keratin cells. It is not a true tooth. The claws are keratinised epidermal appendages of the digits or toes. The claw root epidermis gives rise to columns of flattened keratinised cells that remain firmly stuck together.

21. Feathers Birds are almost completely covered with feathers. During the evolutionary process of the poultry, most of the reptilian scales changed to feathers. Both scales and feathers are chiefly composed of the same protein and keratin. Feathers serve many purposes such as: Helps in flying Providing insulation from extremes of temperature (heat and cold) The condition of the feathers often serves to indicate whether a bird is sick or healthy. The feathers serve as insulation and the heat loss is roughly proportional to the surface area of the body. The weight of feathers apparently varies from about 4 to 8 per cent of live body weight with a difference being related to age, sex etc. Older male birds have a lower percentage of feathers than the females and younger birds. The number of feathers on birds in most of the breed varies from about 6,000 to 9,500. The order of the appearance of the various feather tracts is: shoulder and thigh; rump and breast; neck, abdomen and leg; back, wing coverts and head.

22. There are five types of feathers Contour feathers Plumules Filoplumes Down Bristles

23. 1. Contour feathers Outermost feathers present on birds, covering the wings, tail and body They make up the colour and shape of bird. Useful for distinguishing the breeds. They consists of Shaft or rachis parallel barbs barbules barbicels or hooklets aftershaft or hyporachis calamus or quill

24. Wing feathers Remiges Primary and secondary flight feathers separated by axial feather 10 primary feathers Larger Tail feathers Reticles Coverts present at the base of remiges and reticles

25. 2. Plumules --- present beneath the contour feathers, forms a soft downy undercoat. They have a short shaft with radiating free barbs and barbules, lacks interlocking barbicels or hooklets These plumules helps in trapping air to provide warmth 3.Filoplumules --- very small hair like with rudimentary barbs and barbules confined to tip region 4. Down feathers ---- short, fluffy feathers present on a newly hatched chick, resembles plumules with multiple radiating barbs. 5. Bristles---- present around the eyes and mouth, similar to eyelashes Sensory function