Equine

Any member of the ungulate family Equidae, which includes the modern horses, zebras, and asses, all in the genus Equus, as well as more than 60 species known only from fossils. Equines descended from the dawn horse (see Eohippus). Wild horses, which once inhabited much of northern Eurasia, were smaller and had shorter legs than their domesticated descendants. See also Przewalski's horse.

Ungulate

Any hoofed, herbivorous, quadruped, placental mammal in three or four orders: Artiodactyla, the even-toed ungulates (including pigs, camels, deer, and bovines); Perissodactyla, the odd-toed ungulates (including horses, tapirs, and rhinoceroses); Proboscidea (elephants); and, by some authorities, Hyracoidea (see hyrax). There are ten orders of extinct ungulates. The hoof is dermal tissue, comparable to the human fingernail, that extends over the end of a broadened terminal digit. See also ruminant.

horse (ho´rs)
n.

1.  
1. A large hoofed mammal (Equus caballus) having a short-haired coat, a long mane, and a long tail, domesticated since ancient times and used for riding and for drawing or carrying loads.
2. An adult male horse; a stallion.
3. Any of various equine mammals, such as the wild Asian species E. przewalskii or certain extinct forms related ancestrally to the modern horse.
2. A frame or device, usually with four legs, used for supporting or holding.
3. Sports. A vaulting horse.
4. Slang. Heroin.
5. Horsepower. Often used in the plural.
6. Mounted soldiers; cavalry: a squadron of horse.
7. Geology.
1. A block of rock interrupting a vein and containing no minerals.
2. A large block of displaced rock that is caught along a fault.

Mustangs

Many mustangs are descendants of sixteenth-century Spanish explorers' imported horses that had escaped and adapted to wilderness conditions. Modern feral horses represent hybrids of numerous breeds and primarily live in western states.

Books and movies usually depict mustangs sentimentally as symbols of freedom. In fact, mustangs often suffer starvation because fires, droughts, and urbanization destroy grazing sites. Pathogens spread fatal diseases in mustang herds. Mustangs occasionally die during natural disasters. Wild animals prey on mustangs. Humans sometimes poach mustangs to sell their carcasses.

The federal government approved extermination of the estimated 2 million mustangs living on public ranges in the 1930s. During the 1950s, Velma "Wild Horse Annie" Johnston (1912–1977) lobbied Congress to halt mustang slaughtering. Nevada legislation forbade contamination of water sources and use of aircraft to hunt mustangs. The federal government designated the Pryor Mountain Wild Horse Range in 1968. By 1971, Congress passed the Wild Free-Roaming Horse and Burro Act to protect mustangs in the Bureau of Land Management's (BLM) jurisdiction. The BLM established Herd Management Areas (HMA). The Wild Horse and Burro Preservation and Managment Act of 1999 assured additional federal protection. BLM personnel round up mustangs for public adoption. The Spanish Mustang Registry, Incorporated, and North American Mustang Association and Registry document mustangs. Sanctuaries protect some mustangs, including two HMAs that help Kiger Mustangs, which genetic tests indicate possess distinctive Spanish Barb traits.