The donkey or ass is a domesticated equine. It derives from the African wild ass, Equus africanus, and may be classified either as a subspecies thereof, Equus africanus asinus, or as a separate species, Equus asinus. It was domesticated in Africa some years ago, and has been used mainly as a working animal since that time.

There are more than 40 million donkeys in the world, mostly in underdeveloped countries, where they are used principally as draught or pack animals. While working donkeys are often associated with those living at or below subsistence, small numbers of donkeys or asses are kept for breeding, as pets, and for livestock protection in developed countries.

An adult male donkey is a jack or jackass, an adult female is a jenny or jennet, The change may have come about through a tendency to avoid pejorative terms in speech and may be comparable to the substitution in North American English of rooster for cock. By the end of the 17th century, changes in pronunciation of both ass and arse had caused them to become homophones in some varieties of English. Other words used for the ass in English from this time include cuddy in Scotland, neddy in southwestern England and dicky in southeastern England; moke is documented in the 19th century and may be of Welsh or Romani origin.

Burro is a word for donkey in both Spanish and Portuguese. In the United States, it is commonly applied to the feral donkeys that live west of the Rocky Mountains;

Molecular phylogenies indicate the most recent common ancestor of all modern equids (members of the genus Equus) lived ~5.6 (3.9–7.8) mya. Direct paleogenomic sequencing of a 700,000-year-old middle Pleistocene horse metapodial bone from Canada implies a more recent 4.07 Myr before present date for the most recent common ancestor (MRCA) within the range of 4.0 to 4.5 Myr BP. The oldest divergencies are the Asian hemiones (subgenus E. (Asinus), including the kulan, onager, and kiang), followed by the African zebras (subgenera E. (Dolichohippus), and E. (Hippotigris)). All other modern forms including the domesticated horse (and many fossil Pliocene and Pleistocene forms) belong to the subgenus E. (Equus) which diverged ~4.8 (3.2–6.5) million years ago.

The ancestors of the modern donkey are the Nubian and Somalian subspecies of African wild ass. Remains of domestic donkeys dating to the fourth millennium BC have been found in Ma'adi in Lower Egypt, and it is believed that the domestication of the donkey was accomplished long after the domestication of cattle, sheep and goats in the seventh and eighth millennia BC. Donkeys were probably first domesticated by pastoral people in Nubia, and they supplanted the ox as the chief pack animal of that culture. Genetic evidence indicates that the Cushitic-speaking peoples in the Horn of Africa and along the Red Sea Hills separately domesticated the animal. The domestication of donkeys served to increase the mobility of pastoral cultures, having the advantage over ruminants of not needing time to chew their cud, and were vital in the development of long-distance trade across Egypt. In the Dynasty IV era of Egypt, between 2675 and 2565 BC, wealthy members of society were known to own over 1,000 donkeys, employed in agriculture, as dairy and meat animals and as pack animals. Some researchers believe the actual number may be somewhat higher since many donkeys go uncounted.

Characteristics

Donkeys vary considerably in size, depending on both breed and environmental conditions, and heights at the withers range from less than to approximately . Working donkeys in the poorest countries have a life expectancy of 12 to 15 years; Donkeys have large ears, which may pick up more distant sounds, and may help cool the donkey's blood. Donkeys can defend themselves by biting, striking with the front hooves or kicking with the hind legs. Their vocalization, called a bray, is often represented in English as "hee haw".

Cross on back

Most donkeys have dorsal and shoulder stripes, primitive markings which form a distinctive cross pattern on their backs.

Breeding

thumb|A three-week-old donkey foal

A jenny is normally pregnant for about 12 months, though the gestation period varies from 11 to 14 months, and usually gives birth to a single foal. Births of twins are rare, though less so than in horses. In general jennies have a conception rate that is lower than that of horses (i.e., less than the 60–65% rate for mares). The time lapse involved in rebreeding, and the length of a jenny's gestation, means that a jenny will have fewer than one foal per year. Because of this and the longer gestation period, donkey breeders do not expect to obtain a foal every year, as horse breeders often do, but may plan for three foals in four years.

Although formal studies of their behaviour and cognition are rather limited, donkeys appear to be quite intelligent, cautious, friendly, playful, and eager to learn.

Uses

<gallery mode="packed" heights="200px" style="text-align:left; font-size:94%">

File:Skegness4web.jpg|Classic British seaside donkeys in Skegness

File:104 Donkeys in Tayrona Park Colombia.JPG|Pack donkeys in Tayrona National Natural Park in northern Colombia

File:Esel auf Ydra.jpg|Donkeys for transport on the island of Hydra

File:Uyghur man on his donkey cart. Kashgar.jpg|Uyghur man on his donkey cart. Kashgar

File:Donkey Equus asinus Tanzania 1114 cropped Nevit.jpg|A donkey in Tanzania.

</gallery>

The donkey has been used as a working animal for at least years. Of the more than 40 million donkeys in the world, about 96% are in underdeveloped countries, where they are used principally as pack animals or for draught work in transport or agriculture. After human labour, the donkey is the cheapest form of agricultural power. When working as livestock guard animals, also called predator control animals or mobile flock protectors, donkeys will bray loudly and attack potential predators by kicking out with their front hooves.

A few donkeys are milked or raised for meat. In Italy, which has the highest consumption of equine meat in Europe and where donkey meat is the main ingredient of several regional dishes, about 1,000 donkeys were slaughtered in 2010, yielding approximately of meat.

thumb|upright|Lt. Richard Alexander "Dick" Henderson using a donkey to carry a wounded soldier at the [[Battle of Gallipoli]]

In China, donkey meat is considered a delicacy with some restaurants specializing in such dishes, and Guo Li Zhuang restaurants offer the genitals of donkeys in dishes. Donkey-hide gelatin is produced by soaking and stewing the hide to make a traditional Chinese medicine product. Ejiao, the gelatine produced by boiling donkey skins, can sell for up to $388 per kilogram, at October 2017 prices.

In warfare

During World War I John Simpson Kirkpatrick, a British stretcher bearer serving with the Australian and New Zealand Army Corps, and Richard Alexander "Dick" Henderson of the New Zealand Medical Corps used donkeys to rescue wounded soldiers from the battlefield at Gallipoli.

Care

Shoeing

Donkey hooves are more elastic than those of horses, and do not naturally wear down as fast. Regular clipping may be required; neglect can lead to permanent damage. Donkeys are also less prone to colic. In temperate climates the forage available is often too abundant and too rich; over-feeding may cause weight gain and obesity, and lead to metabolic disorders such as founder (laminitis) and hyperlipaemia, In Australia, where there may be 5 million feral donkeys,

A male donkey (jack) crossed with a female horse produces a mule, while a male horse crossed with a jenny produces a hinny. Horse–donkey hybrids are almost always sterile because of a failure of their developing gametes to complete meiosis. The lower progesterone production of the jenny may also lead to early embryonic loss. In addition, there are reasons not directly related to reproductive biology. Due to different mating behavior, jacks are often more willing to cover mares than stallions are to breed jennies. Further, mares are usually larger than jennies and thus have more room for the ensuing foal to grow in the womb, resulting in a larger animal at birth. It is commonly believed that mules are more easily handled and also physically stronger than hinnies, making them more desirable for breeders to produce.

The offspring of a zebra–donkey cross is called a zonkey, zebroid, zebrass, or zedonk;

<!--unused-->

<!---ref name=iucn>Moehlman, P.D.; H. Yohannes; R. Teclai; F. Kebede (2008) Equus africanus, in: IUCN 2008. IUCN Red List of Threatened Species. Retrieved February 2012.</ref>

--->

<!---ref name=nowak></ref--->