The donkey is a domesticated member of the horse family, Equidae. It is also referred to as an ass, Equus africanus, and Equus Asinus. The wild ancestor of the donkey is the African wild ass, E. africanus. Donkeys been used as a working animals for at least 5000 years. There are more than 40 million world wide; mostly in underdeveloped countries, where they are used principally as draught or pack animals. Working donkeys are often associated with those living at or below subsistence levels. Small numbers of donkeys are kept for breeding or as pets in developed countries.
For an historical perspective asses were first domesticated around 3000 BC, probably in Egypt or Mesopotamia. Their numbers have spread around the world. The donkey fills important roles around the world--even today. While domesticated species are increasing in numbers, the African wild ass and another relative, the onager, are endangered. (The Onager aka Equus hemionus is a large member of the genus Equus of the family Equidae aka horse family native to the deserts of Syria, Iran, Pakistan, India, Israel and Tibet. It is sometimes known as the Wild Asian Ass.) As beasts of burden and companions, asses and donkeys have worked together with humans for millennia.
Scientific and Common Names
Traditionally, the scientific name for the donkey is Equus asinus asinus based on the principle of priority used for scientific names of animals. However, the International Commission on Zoological Nomenclature ruled in 2003 that if the domestic species and the wild species are considered subspecies of each other, the scientific name of the wild species has priority, even when that subspecies was described after the domestic subspecies. This means that the proper scientific name for the donkey is Equus africanus asinus when it is considered a subspecies, and Equus asinus when it is considered a species. ...
...From the 18th century, donkey gradually replaced ass. The change may have come about through a tendency to avoid pejorative terms in speech, and be comparable to the substitution in North American English of rooster for cock, or that of rabbit for coney, which was formerly homophonic with cunny. By the end of the 17th century, changes in pronunciation of both ass and arse had caused them to become homophones. Other words used for the ass in English from this time include cuddy in Scotland, neddy in southwest England and dicky in the southeast; moke is documented in the 19th century, and may be of Welsh or Gypsy origin. In the United States, the Spanish burro is used both specifically for the feral donkeys of Arizona, California and Nevada, and, west of the Mississippi, generically for any small or standard donkey.
Characteristics
Donkeys are adapted to marginal desert lands. Unlike wild and feral horses, wild donkeys in dry areas are solitary and do not form harems. Each adult donkey establishes a home range; breeding over a large area may be dominated by one jack. The loud call or bray of the donkey, which typically lasts for twenty seconds and can be heard for over three kilometres, may help keep in contact with other donkeys over the wide spaces of the desert. 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.
Breeding
A male donkey or ass is called a jack, a female a jenny or jennet; a young donkey is a foal. A male donkey (jack) can be crossed with a female horse to produce a mule. A jennet 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. About 1.7 percent of donkey pregnancies result in twins; both foals survive in about 14 percent of those. Although jennets come into heat within 9 or 10 days of giving birth, their fertility remains low and it is usual to wait one or two further oestrous cycles before rebreeding. 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.
Donkeys can interbreed with other members of the family Equidae, and are commonly interbred with horses. The hybrid between a jack and a mare is a mule, valued as a working and riding animal in many countries. Some large donkey breeds such as the Asino di Martina Franca, the Baudet de Poitou and the Mammoth Jack are raised only for mule production. The hybrid between a stallion and a jennet is a hinny, and is less common. Like other inter-species hybrids, mules and hinnies are usually sterile. Donkeys can also breed with zebras in which the offspring is called a zebroid 
(also zedonk, zorse, zebra mule, zonkey, and zebrule).
Behavior
Donkeys have a notorious reputation for stubbornness, but this has been attributed to a much stronger sense of 'self preservation' than exhibited by horses. Likely based on a stronger prey instinct and a weaker connection with man, it is considerably more difficult to force or frighten a donkey into doing something it perceives to be dangerous for whatever reason. Once a person has earned their confidence they can be willing and companionable partners and very dependable in work. Although formal studies of their behavior and cognition are rather limited, donkeys appear to be quite intelligent, cautious, friendly, playful, and eager to learn. ...
Present Status
About 41 million donkeys were reported worldwide in 2006. China has the most with 11 million, followed by Pakistan, Ethiopia and Mexico. Some researchers believe the actual number is somewhat higher since many donkeys go uncounted. The number of breeds and percentage of world population for each of the FAO's world regions was in 2006:
In 1997 the number of donkeys in the world was reported to be continuing to grow, as it had steadily done throughout most of history; factors cited as contributing to this were increasing human population, progress in economic development and social stability in some poorer nations, conversion of forests to farm and range land, rising prices of motor vehicles and fuel, and the popularity of donkeys as pets. Since then, the world population of donkeys is reported to be rapidly shrinking, falling from 43.7 million to 43.5 million between 1995 and 2000, and to only 41 million in 2006. The fall in population is pronounced in developed countries; in Europe, the total number of donkeys fell from 3 million in 1944 to just over 1 million in 1994.
The Domestic Animal Diversity Information System (DAD-IS) of the FAO listed 189 breeds of ass in June 2011. In 2000 the number of breeds of donkey recorded worldwide was 97, and in 1995 it was 77. The rapid increase is attributed to attention paid to identification and recognition of donkey breeds by the FAO's Animal Genetic Resources project . The rate of recognition of new breeds has been particularly high in some developed countries. In France, for example, only one breed, the Baudet de Poitou , was recognized prior to the early 1990s; by 2005, a further six donkey breeds had official recognition. In prosperous countries, the welfare of donkeys both at home and abroad has become a concern, and a number of sanctuaries for retired and rescued donkeys have been set up. The largest is the Donkey Sanctuary of England, which also supports donkey welfare projects in Egypt, Ethiopia, India, Kenya, and Mexico.
Donkey Uses
Donkeys have been used for many purposes, by humans, over time. They are used in warfare, for economic purposes, pack animals, transportation, as a working animal for draft and agriculture purposes, for threshing, raising water, milling, to sire mules, to guard sheep, as companion animals to horses and ponies, as a baby sitter animal after a horse or pony foal has been weaned from its mother, for milk and meat, for use in making soaps and cosmetics, for dietary purposes, medicinal purposes, for the making of parchment and as a pet.
Nutrition
Woolly páramo Donkey An endangered species of donkey is the Woolly Paramo Donkey. It can be found in high elevations of up to 3,000 m altitude and the permanent snow line of about 5,000 meters. It can be found in Colombia.
Throughout the world, working donkeys are associated with the very poor, with those living at or below subsistence level. Few receive adequate food, and in general donkeys throughout the Third World are under-nourished and over-worked. 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 , or to gastric ulcers.
Feral Donkeys and Wild Asses
In some areas domestic donkeys have returned to the wild and established feral populations such as those of the Burro of North America and the Asinara donkey of Sardinia, Italy, both of which have protected status. Feral donkeys can also cause problems, notably in environments that have evolved free of any form of equid, such as Hawaii. In Australia, where there may be 5 million feral donkeys, they are regarded as an invasive pest and have a serious impact on the environment. They may compete with livestock and native animals for resources, spread weeds and diseases, foul or damage watering holes and cause erosion.
Wild asses, onagers, and kiangs
Few species of ass exist in the wild. The African wild ass, Equus africanus, has two subspecies, the Somali wild ass, Equus africanus somaliensis, and the Nubian wild ass, Equus africanus africanus, the principal ancestor of the domestic donkey. Both are critically endangered. Extinct species include the European ass, Equus hydruntinus, which became extinct during the Neolithic, and the North African wild ass, Equus africanus atlanticus, which became extinct in Roman times. There are five subspecies of Asiatic wild ass or onager, Equus hemionus, and three subspecies of the kiang, Equus kiang, of the Himalayan upland.
Donkey Hybrids
Horse-donkey hybrids are almost always sterile because horses have 64 chromosomes whereas donkeys have 62, producing offspring with 63 chromosomes. Mules are much more common than hinnies. This is believed to be caused by two factors, the first being proven in cat hybrids, that when the chromosome count of the male is the higher, fertility rates drop (as in the case of stallion x jennet). 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 jennys. Further, mares are usually larger than jennys 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, and it is unquestioned that mules are more common in total number.
The offspring of a zebra-donkey cross is called a zonkey, zebroid, zebrass, or zedonk; zebra mule is an older term, but still used in some regions today. The foregoing terms generally refer to hybrids produced by breeding a male zebra to a female donkey. Zebra hinny, zebret and zebrinny all refer to the cross of a female zebra with a male donkey. Zebrinnies are rarer than zedonkies because female zebras in captivity are most valuable when used to produce full-blooded zebras. There are not enough female zebras breeding in captivity to spare them for hybridizing; there is no such limitation on the number of female donkeys breeding.
Colloquialisms, Proverbs and Insults
The words 'donkey' and 'ass'...have come to have derogatory or insulting meaning in several languages, and are generally used to mean someone who is obstinate, stupid or silly. In football, especially in the United Kingdom, a player who is considered unskilful is often dubbed a 'donkey', and the term has a similar connotation in poker. In the US, the slang terms 'dumbass' and 'jackass' are used to refer to someone considered stupid. Many cultures have colloquialisms and proverbs that include donkeys or asses.
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