History
In the 1600s, American colonists on the eastern seaboard began to cross imported English horses with "native" horses such as the Chickasaw (a breed developed by Native American people from horse descended from Spanish, Arabian and Barb stock brought to what is now the Southeastern United States by the Conquistadors). One of the most famous of these early imports was Janus, a Thoroughbred who was the grandson of the Godolphin Arabian. He was foaled in 1746, and imported to colonial Virginia in 1756. The influence of Thoroughbreds like Janus contributed genes crucial to the developement of the colonial "Quarter Miler," or "Quarter Mile Horse." This was a speedy working man's racer, sometimes referred to as the "Celebrated American Quarter Running Horse." The resulting horse was small, hardy, and quick, and was used as a work horse during the week and a race horse on the weekends.
As flat racing became popular with the colonists, the Quarter Miler gained even more popularity as a sprinter over courses that, by necessity, were shorter than the classic racecourses of England, and were often no more than a straight stretch of road or flat piece of open land. When matched against a Thoroughbred, local sprinters often won. As the Thoroughbred breed became established in America, many colonial Quarter Mile mares were included in the original American stud books, starting a long association between the Thoroughbred breed and what would later become officially known as the "Quarter Horse," named after the distance at which it excelled.
In the 1800s, pioneers heading West needed a hardy, willing horse. On the Great Plains, settlers encountered horses that descended from the Spanish stock Hern n Cort s and other Conquistadors had introduced into the viceroyalty of New Spain, which today includes the Southwestern United States and Mexico. These horses of the west included herds of feral animals known as Mustangs, as well as horses domesticated by Native Americans, including the Comanche, Shoshoni and Nez Perce tribes. As the colonial Quarter Mile Horse was crossed with these western horses, the pioneers found that the new crossbred had innate "cow sense," a natural instinct for working with cattle, making it popular with cattlemen on ranches.
The main duty of the ranch horse in the American west was working cattle. Even after the invention of the automobile, horses were still irreplacable for handling livestock on the range. Thus, major Texas cattle ranches, such as the King Ranch, the 6666 (four sixes) ranch, and the W.T. Waggoner ranch played a significant role in the development of the modern Quarter Horse.
The skills needed by ranch hands and their horses became the foundation of the sport of rodeo, a contest which began with informal competition between cowboys and expanded to become a major competitive event throughout the west. To this day, the Quarter Horse dominates the sport both in speed events and in competition that emphasizes the handling of live cattle.
However, sprint races were also popular weekend entertainment and racing became a source of economic gain for breeders as well. As a result, more Thoroughbred blood was added back into the developing Quarter horse breed. The Quarter Horse also benefitted from the addition of Arabian, Morgan and even Standardbred bloodlines.
In 1940, the Quarter Horse Association (AQHA) was formed by a group of horsemen and ranchers from the southwestern United States dedicated to preserving the pedigrees of their ranch horses. The first horse registered was Wimpy, a descendant of the King Ranch foundation sire Old Sorrel. Major foundation sires registered by the AQHA included King, Peppy, Leo, Poco Bueno, Three Bars (a Thoroughbred), and Joe Hancock. Other thoroughbred sires seen in early Quarter Horse pedigrees include King Plaudit, Blob, Johnny Dial, Top Deck, Vandy, and Truckle Feature.
Since the Quarter Horse formally established itself as a breed, the AQHA stud book has remained open to Thoroughbreds. Quarter Horse/Thoroughbred crosses are entered into the registry as "Appendix Quarter Horses." These animals are popular for Quarter Horse Racing and for Jumping and Hunter events. After meeting a series of conformational and performance criteria, these Appendix Quarter Horses can obtain permanent registration numbers. Since Quarter Horse/Thoroughbred crosses continue to have an opportunity to enter the official registry of the Quarter Horse breed, this is creating a continual gene flow from the Thoroughbred breed into the Quarter Horse breed, which has been influential in altering many of the characteristics that typified the breed in the early years of its formation.
Health
Hyperkalemic periodic paralysis (HYPP), which is caused by an autosomal dominant gene linked to the stallion Impressive. It is characterized by uncontrollable muscle twitching and substantial muscle weakness or paralysis among affected horses. Because it is a dominant gene, only one parent has to have the gene for it to be transmitted to offspring. There is a DNA test for HYPP, the AQHA requires testing and is now limiting registration of some horses who possess the gene.
Hereditary Equine Regional Dermal Asthenia (HERDA), also known as hyperelastosis cutis (HC). This is caused by a recessive gene, and thus, unlike HYPP, HERDA can only be transmitted if both parents carry the gene. When a horse has this disease, there is a collagen defect that results in the layers of skin not being held firmly together. Thus, when the horse is ridden under saddle or suffers trauma to the skin, the outer layer often splits or separates from the deeper layer, or it can tear off completely. It rarely heals without disfiguring scars. Sunburn can also be a concern. In dramatic cases, the skin can split along the back and even roll down the sides, with the horse literally being skinned alive. Most horses with HERDA are euthanized for humane reasons between the age of two and four years. The very hotly debated and controversial theory, put forth by researchers at Cornell University and Mississippi State University is that the sire line of the great foundation stallion Poco Bueno is implicated as the origin of the disease. There currently is no DNA test for HERDA, but active research is ongoing to try and pinpoint the gene.
