Billy Goat - Anatomy and Health

Anatomy and Health

Goats are considered small livestock animals, compared to bigger animals such as cattle, camels and horses, but larger than microlivestock such as poultry, rabbits, cavies, and bees. Each recognized breed of goats has specific weight ranges, which vary from over 300 lbs for bucks of larger breeds such as the Boer, to 45 to 60 lbs for smaller goat does. 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 Pigmy, which stand 16 to 23 inches at the shoulder as adults.

Most goats naturally have two horns, of various shapes and sizes depending on the breed. Goats have horns unless they are "polled" (meaning, genetically hornless) or the horns have been removed, typically soon after birth. There have been incidents of polycerate goats (having as many as eight horns), although this is a genetic rarity thought to be inherited. The horns are most typically removed in commercial dairy goat herds, to reduce the injuries to humans and other goats. 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.

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.

Goats have horizontal, slit-shaped pupils, an adaptation which increases peripheral depth perception. 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.

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.

Some breeds of sheep and goats look similar, but they can usually be told apart because goat tails are short and usually point up, whereas sheep tails hang down and are usually longer and bigger – though some (like those of Northern European short-tailed sheep) are short, and longer ones are often docked.