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Body covers and shields

Hunting zoology is a branch of natural sciences, dealing with the study of the habits of the game (behavior). It deals with internal and external morphology , physiological processes and behavior of animals. These data are extremely valuable for the active protection of fauna.

Body covers and shields

Birds and mammals are warm-blooded animals and the structure of the skin and its cover products is adapted to this requirement., that is feathers and hair. The top, quite a stiff layer is formed by the epithelium (epidermis). Below it is the dermis - the zone of cellular reproduction, causing the formation of horny formations such as horns and antlers, claws and hoof capsule or hoof caps. The skin of birds is less dense than that of mammals, and it is most delicate in barn owls.

The feather is another shielding entity. We know two main types: shuttlecocks and down feathers. The ailerons consist of a scape that extends the feather axis, having on both sides flags growing in one plane. These feathers are quite stiff and are used to protect the body of the birds, giving it aerodynamic shapes. Down feathers have a short axis and flags without hooks. Down is a cover for young birds, and in adults, an insulating layer under the cover feathers.

Feathers are renewed every year, permanently or once in a given period. In some species, moulting occurs once a year (goose), others change feathers twice (ducks). Most birds moult twice a year. Only a few species moult three times a year (pardwa). If the bird renews its plumage many times a year, does not replace all pens at once. Moulting affects only certain parts of the body. The ailerons may be renewed gradually (birds of prey, kuraki) or disposable (ducklings). In the second case, when all the ailerons drop simultaneously, the birds are unable to fly for three to seven weeks.

During the life of the bird, the plumage changes many times. Chick fluff is replaced by juvenile plumage, which goes away the next year (pheasants, crests) or a few years later (eagles) the robes of adults.

There are two types of plumage in mature birds: mating plumage, colors, appearing in males during the mating season and during nesting (Look: crossword) and winter or summer plumage, less colorful, which grows up after the annual moulting, after the end of the mating season. During this period, the coloration of males is similar to that of females.

Mammalian hairs also take two forms. Down hair is short and fine and provides good heat insulation. The topcoat hair is stiff, longer and coarser. The shedding of hair occurs twice a year: in spring and early winter. The summer coat is shorter, less dense and often of a different color than winter - long and dense (Look: sarna, ermine).

There are various glands in the skin of mammals. The skin of the birds is devoid of them. Only the rump gland is present. It is highly developed in waterbirds, in which the secretion of this gland ensures waterproof plumage. In such species, like pigeons and parrots he is in a state of decay, and in some others it does not occur at all.

Mammalian skin contains sweat glands that play an essential role in physiological changes and in regulating body temperature. The sebaceous glands lubricate the outer layer of the skin, hair and claws. Scent glands, which arose from the transformation of the sebaceous and sweat glands, they are important in intra-species and interspecies communication between animals. Mammals in their biotope orient themselves mainly through smells; they enable gender recognition, they are used for territory significance and, in some species, for defense (coward). Deer leave scent gland secretions on trees or bushes, foxes mix it with their droppings, the deer leave her on their own track.

The scent glands are arranged differently, depending on the genus and species: at the foxes, In badgers and hares, there are sexo-anal glands, in podoczodołowe deer (lacrimal glands). The scent glands in chamois are located at the base of the horns, in hares under the cheeks and over the nostrils, in numerous deer - between the hooves.

The mammary glands were formed as a result of the transformation of the sweat glands. They are unique to mammals, milk secretion does not begin until after delivery. The mammary glands develop in the nipples.

Another cover product is the bird's beak. Composed of calloused plates covering the jaws, has different shapes. It is used to catch food, carrying items, recognizing them, to attack the opponent or to defend. The hooked beak of birds of prey makes it easier to slice up the prey, the duck's beak is flat and edged with external gills used to filter food particles from the water or to nibble at grass. Thin, pliers-shaped, the snipe's beak is used to search for worms in the silt. The Gray Heron uses its beak like a harpoon when catching fish, the beak of the grouse is short and strong, because it is used for pecking.

Claws and hooves are also callous ground coverings. The claws of birds and mammals cover the last fingers. Daily raptors have strong and curved claws. They use them to grab prey and tear it apart. Ground-digging hens have broad and short nails. Fawn predators have especially strong and sharp claws. Lynx and bears use them to capture prey, foxes for digging burrows, food-digging badgers. Feline claws are retracted. They only extend them when defending or attacking prey. So the claws of a cat or a lynx are invisible on the tracks. Racice are the callous cover of the last members of the third and fourth ungulate fingers. The last members of the second and fifth fingers are atrophic and located slightly higher on the back of the limb. They are also provided with a callous coating.

The hoof horn is a covering product found in some ungulates, like a mouflon, chamois and many others. The horns cover a bony growth on the forehead. They grow continuously from the base, so their top is necessarily the oldest part.