Equus(redirected from Equus zebra)
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a genus of perissodactyls of the family Equidae. The Equus are large (body length to 2.5 m, height at the withers to 1.6 m), well-proportioned animals. The legs are long, with only one (the middle) developed toe, which is encased in a hoof—an adaptation for running swiftly on solid ground. The body is covered with short thick hairs. There are long hairs on the upper side of the neck (the mane) and similar hairs on the tip of the tail (on the entire tail in some animals). The cheek teeth have flat square crowns—an adaptation for grinding coarse vegetation. In the wild state, the Equus were distributed in Europe, where they have been exterminated, and in Asia and Africa; they usually lived in herds in steppes, deserts, and semideserts, feeding on grasses.
There are eight species, grouped into four subgenera: Equus (the horses), which includes Przewalski’s horse, the extinct tarpan, and the domestic horse; Asinus (the asses), which is represented by the wild African ass and the domestic ass; Hemonius (the wild Mongolian asses), represented by the onager; and Hip potigris (the zebras). In addition to the domestic horse and ass, the onager is also found in the USSR; the tarpan lived in the southern steppes until the 1870’s. Most of the wild species of Equus have been wiped out, and those remaining are protected.
I. I. SOKOLOV
Domestic horse. The domestic horse (Equus caballus) is found on all the continents except Antarctica and in most countries. It is used as a work animal and as a source of milk and meat; it is also used for sport (flat and harness racing, horse shows). The horse was first domesticated in the third millennium B.C. There were apparently several large independent regions of domestication—the steppes between the Don and Dnieper rivers, southern Siberia, and Middle Asia, to mention a few.
There are more than 200 breeds of horses in the world raised for different purposes; there are 50 breeds in the USSR. Horse breeds differ in type, conformation, size, and work capacity. They are classified into several basic groups. A large group of modern horse breeds, specialized according to capacity for work, has been developed under minimum influence of natural climatic conditions. This group comprises (1) the draft breeds, including the Vladimir, Russian, Soviet, and Lithuanian breeds in the USSR and the Ardennes, Belgian, Brabant, Percheron, Clydesdale, Suffolk, and Shire horses of other countries; (2) the light harness breeds, including the Orlov and Russian trotters (Metis) in the USSR and the Norfolk and Dutch trotters and the American Standardbred horse abroad; (3) the harness breeds, including the Toric (Torsky), Kuznetsk, and Latvian breeds in the USSR and the Nonius (Hungary), Finnish, Oldenburg, and Kladruby (Kladruber) horses abroad; (4) the saddle and harness breeds, including the North Star, Furioso, and Gidran (Hungary) horses and the Great Polish, German, Brandenburg, Holstein, and Hanoverian horses; and (5) the saddle breeds, including the Thoroughbred (England), German, and Trakehner horses, which are raised in many countries, and the Budennyi and Terek horses in the USSR. The Polish Saddle horse, the Andalusian horse (Spain), the American Saddle horse, and others are raised in foreign countries in addition to the Thoroughbred.
Some breeds of horses are raised in various localities under conditions close to natural climatic conditions. Like those of the first group, these breeds have a great capacity for work but differ in their better adaptation to the climate, terrain, and use of pasture forages. They are divided into regional groups: (1) the steppe saddle and harness breeds, including the Don, Kustanai, and Canadian horses; (2) the mountain saddle, pack, and harness breeds, including the Kabardinian, New Kirghiz, Lokai and Karabakh horses; and (3) the breeds of the southern deserts and oases, including the Achal Teke (Akhaltekinskaia), Arabian, Karaib, Iomud, and Barbary horses.
There is also a large group of local breeds that are bred using a lower level of zootechnical techniques. These are mainly work and combination work, meat, and dairy breeds noted for their endurance and adaptability to local conditions; they are usually small. These breeds have been grouped according to locality: (1) the northern local harness breeds, including the Viatka, Pechora, Ob’, Narym, Mezen’, Poles’e, lakut, and Estonian horses and the Konik horse (Poland); (2) the steppe breeds, including the Kazakh, Bashkir, Trans-Baikal, Minusinsk, Adaev, and Mongolian horses; (3) the mountain breeds, including the Kirghiz, Altai, Tuva, Azerbaijan, Tusheti, Mingreli, Hutzul, and Haflinger horses; and (4) the island ponies, including the Gotland, Shetland, Highland, Iceland, Corsican, Sardinian, and Hokkaido ponies.
With the development of mechanization and automation in agriculture in the mid-20th century, most countries with a significant horse population have developed breeds for sport (trotters, saddle horses), tourism (pack, saddle, and harness horses), and the production of horsemeat and koumiss (meat and dairy breeds).
Modern horse breeds measure from 50 to 185 cm high at the withers and weigh from 60 to 1,500 kg. Because of their keen senses of hearing and smell and their good memories, they are easily trained. They reach sexual maturity at 1 1/2 years but become economically feasible to breed at three to 3 1/2 years; physical maturity is attained at five to six years. The gestation period is approximately 11 months; the female (mare) gives birth as a rule to one young (foal), which suckles for six to eight months. The milk productivity of mares ranges from 11 to 15 liters per day, but outstanding milkers can give as much as 25 liters. This makes it possible to raise a foal and still use a significant quantity of the milk for koumiss, a product made from fermented mare’s milk. Foals of trotter and saddle breeds raised on stud farms begin their racing training at 1 1/2 years of age in order to develop greatest speed (at the trot, pace, and gallop) and endurance. Trotters and saddle horses are first raced at two years. Draft breeds are trained for work at two years. Meat breeds are slaughtered at 1 1/2 to two years, when the quality of horsemeat is best (18-20 percent protein, 6-8 percent fat). Slaughter yield is 50-60 percent, depending on the animal’s fatness. The life expectancy of a horse is 25-30 years; the period of economic usefulness is 14-15 years, and of breeding usefulness 20-25 years.
The quality of a horse and its capacity for work and long-term usefulness are determined to a significant extent by how the horse is fed and kept. When maintained in stalls, horses are fed primarily oats, barley, rye, corn combined with other concentrated feeds (bran and meal), grass and legume hay, succulent feeds (carrots, semisugar beets, potatoes, silage), or mixed feeds. When kept on pastures, horses feed on the green grass or freshly mown grass; they are also supplied daily with salt. The amount a horse is fed depends on the animal’s weight, condition, and age and the type of work it performs and the nutritive value of the feed. A horse is allowed to drink its fill of water three times daily. Horses can be kept stabled year-round, stabled part of the time and pastured from spring to fall, or pastured year-round, with supplemental hay and concentrates in winter. Grooming consists in cleaning the horse with brushes, combing the mane and tail, and cleaning out the hooves. Horses are usually shod, which protects the bottoms of the hooves from abrasion and injury.
Stud farms, stables, breeding and artificial insemination stations, racecourses, and breeding farms are involved in improving the quality of horses and in developing new breeds.
In 1971 there were 66.3 million horses in the world, including 7.4 million in the USSR. World records set by specialized horse breeds are in flat racing, for 1,000 m at a gallop, 53.6 sec, set by the four-year-old Thoroughbred stallion Indigenous in 1960, and in harness racing, for 1,609 m at a trotting gait, 1:54.8 sec, set by the four-year-old American Standardbred stallion Nevele Pride in 1969, and for 1,609 m at a pacing gait, 1:52.0 sec, set by the four-year-old American Standardbred pacer Steady Star in 1971. Pulling records are for tractive force in harness, 927.5 kg, set in 1971 by the draft horse Stiprais, a six-year-old Latvian harness horse, and for load-pulling (on a string of wagons), 22,991 kg, set in 1957 by Fors, a six-year-old Soviet draft horse.
Crossbreeding domestic horses with other members of the genus Equus—the asses, zebras, and onagers—results in hybrids, which are usually sterile, such as the mule, hinny, and zebroid. Horses crossed with Przewalski’s horse produce fertile offspring.
REFERENCESSokolov, I. I. “Kopytnye zveri.” Moscow-Leningrad, 1959. (Fauna SSSR: Mlekopitaiushchie, vol. 1, fasc. 3.)
Mlekopitaiushchie Sovetskogo Soiuza, vol. 1. Edited by V. G. Geptner and N. P. Naumov. Moscow, 1961.
Kniga o loshadi, vols. 1-5. Edited by S. M. Budennyi. Moscow, 1952-59.
Konnozavodstvo i konnyi sport Edited by lu. N. Barmintsev. Moscow, 1972.
IU. N. BARMINTSEV