Sheep (Ovis aries) are quadrupedal, ruminant mammal typically kept as livestock. Like most ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Although the name “sheep” applies to many species in the genus Ovis, in everyday usage it almost always refers to Ovis aries. Numbering a little over one billion, domestic sheep are also the most numerous species of sheep. An adult female sheep is referred to as a ewe, an intact male as a ram or occasionally a tup, a castrated male as a wether, and a younger Sheeps as a lamb.
Sheep are most likely descended from the wild mouflon of Europe and Asia. One of the earliest animals to be domesticated for agricultural purposes, sheep are raised for fleece, meat (lamb, hogget or mutton) and milk. A sheep’s wool is the most widely used animal fiber, and is usually harvested by shearing. Ovine meat is called lamb when from younger animals and mutton when from older ones. Sheep continue to be important for wool and meat today, and are also occasionally raised for pelts, as dairy animals, or as model organisms for science.
Sheep husbandry is practised throughout the majority of the inhabited world, and has been fundamental to many civilizations. In the modern era, Australia, New Zealand, the southern and central South American nations, and the British Isles are most closely associated with sheep production.
- Kingdom: Animalia
- Phylum: Chordata
- Class: Mammalia
- Order: Artiodactyla
- Family: Bovidae
- Subfamily: Caprinae
- Genus: Ovis
- Species: O. aries
- Binomial name: Ovis aries
Sheep, ruminant (cud-chewing) mammal of the genus Ovis. The sheep is usually stockier than its relative the goat; its horns, when present, are more divergent it has scent glands in its face and hind feet; and the males lack the beards of goats. Sheep usually have short tails.
In all wild species of sheep, the outer coat takes the form of hair, and beneath this lies a short undercoat of fine wool that has been developed into the fleece of domesticated sheep. Male sheep are called rams, the females ewes, and immature animals lambs. Mature sheep weigh from about 80 to as much as 400 pounds (35 to 180 kg). To browse sheep by breed, see below.
Sheep are a prey species, and their only defense is to flee. Sheep display an intensely gregarious social instinct that allows them to bond closely to other sheep and preferentially to related flock members. Flock mentality movements protect individuals from predators. Flocks include multiple females, offspring, and one or more males. Ewes tend to stay in their maternal groups for life, whereas rams may form transient, unstable, and easily disbanded bachelor herds. If most rams in a group die because of fights or diseases, those remaining join another group. Under standard grazing situations, sheep graze together in casual affiliations; social hierarchies are not as apparent as they are for cattle.
Flock dynamics are apparent in groups of four or more as evidenced by willingness to follow a leader or flee in unison. When escape is prevented, even a ewe may charge or threaten by hoof stomping. Separation from the flock can cause stress and panic. Isolation from other sheep can cause severe stress and should be avoided. Mirrors can be used in the absence of other sheep.
Sheep are exclusively herbivorous mammals. Most breeds prefer to graze on grass and other short roughage, avoiding the taller woody parts of plants that goats readily consume. Both sheep and goats use their lips and tongues to select parts of the plant that are easier to digest or higher in nutrition. Sheep, however, graze well in monoculture pastures where most goats fare poorly.
Domestic sheep are relatively small ruminants, usually with a crimped hair called wool and often with horns forming a lateral spiral.
Domestic sheep differ from their wild relatives and ancestors in several respects, having become uniquely neotenic as a result of selective breeding by humans. A few primitive breeds of sheep retain some of the characteristics of their wild cousins, such as short tails. Depending on breed, domestic sheep may have no horns at all (i.e. polled), or horns in both sexes, or in males only. Most horned breeds have a single pair, but a few breeds may have several.
While sheep are generally a docile, non-aggressive animal, this is not usually the case with rams, especially during the breeding season. Rams can be very aggressive and have been known to cause serious injuries, even death, to people. A ram should never be trusted, even if it is friendly or was raised as a pet. It is important to always know where the ram is and to never turn your back on him. Children should be restricted access to rams during the breeding season.
- Contrary to popular belief, sheep are extremely intelligent animals capable of problem solving. They are considered to have a similar IQ level to cattle and are nearly as clever as pigs.
- Like various other species including humans, sheep make different vocalisations to communicate different emotions. They also display and recognise emotion by facial expressions.
- Sheep are known to self-medicate when they have some illnesses. They will eat specific plants when ill that can cure them.
- Sheep are precocial (highly independent from birth) and gregarious (like to be in a group).
- Female sheep (ewes) are very caring mothers and form deep bonds with their lambs that can recognise them by their call (bleat) when they wander too far away.
- Wild sheep tend to be larger than domesticated species, the largest (Argali) being 1.2m tall. They also have longer horns which they use to defend themselves from predators.