Goat (Capra aegagrus hircus)

The domestic goat or simply goat (Capra aegagrus hircus) is a subspecies of C. aegagrus domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the animal family Bovidae and the goat-antelope subfamily Caprinae, meaning it is closely related to the sheep. There are over 300 distinct breeds of goat. Goats are one of the oldest domesticated species of animal, and have been used for milk, meat, fur, and skins across much of the world. Milk from goats is often turned into goat cheese.

Female goats are referred to as does or nannies, intact males are called bucks or billies and juvenile goats of both sexes are called kids. Castrated males are called wethers. While the words hircine and caprine both refer to anything having a goat-like quality, hircine is used most often to emphasize the distinct smell of domestic goats.

In 2011, there were more than 924 million goats living in the world, according to the UN Food and Agriculture Organization.

Scientific classification
Kingdom:    Animalia
Phylum:    Chordata
Class:    Mammalia
Order:    Artiodactyla
Family:    Bovidae
Subfamily: Caprinae
Genus:    Capra
Species:    C. aegagrus
Subspecies: C. a. hircus

Anatomy and health
Each recognized breed of goat has specific weight ranges, which vary from over 140 kg (300 lb) for bucks of larger breeds such as the Boer, to 20 to 27 kg (45 to 60 lb) for smaller goat does.[8] Within each breed, different strains or bloodlines may have different recognized sizes. At the bottom of the size range are miniature breeds such as the African Pygmy, which stand 41 to 58 cm (16 to 23 in) at the shoulder as adults.

Horns
Most goats naturally have two horns, of various shapes and sizes depending on the breed. There have been incidents of polycerate goats (having as many as eight horns), although this is a genetic rarity thought to be inherited. Unlike cattle, goats have not been successfully bred to be reliably polled, as the genes determining sex and those determining horns are closely linked. Breeding together two genetically polled goats results in a high number of intersex individuals among the offspring, which are typically sterile. Their horns are made of living bone surrounded by keratin and other proteins, and are used for defense, dominance, and territoriality.

Digestion and lactation
Goats are ruminants. They have a four-chambered stomach consisting of the rumen, the reticulum, the omasum, and the abomasum. As with other mammal ruminants, they are even-toed ungulates. The females have an udder consisting of two teats, in contrast to cattle, which have four teats. An exception to this is the Boer goat, which sometimes may have up to eight teats.

Eyes
Goats have horizontal, slit-shaped pupils. Because goats' irises are usually pale, their contrasting pupils are much more noticeable than in animals such as cattle, deer, most horses and many sheep, whose similarly horizontal pupils blend into a dark iris and sclera.

Beards
Both male and female goats have beards, and many types of goat (most commonly dairy goats, dairy-cross Boers, and pygmy goats) may have wattles, one dangling from each side of the neck.
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