The Thoroughbred Horse: Thoroughly Bred For Distance Racing

The Thoroughbred is also known as the Thoroughbred Racehorse even though that is not their only use. While they have historically been bred for racing, their 16 to 17.3 hand height and long legs allow them to excel at jumping and their graceful ways of moving helps the breed to excel at most of the English disciplines such as equitation and dressage.

The Thoroughbred breed includes some of the most valuable animals in the world. In 1985 an untested yearling colt named Seattle Dancer was sold at auction for the record price of $13.1 million just on the basis of his pedigree.

The Thoroughbred pedigree dates back to the late 1600s and may be the oldest recorded pedigree for any animal population. One of the earliest formal registries was the General Stud Book for Thoroughbreds that began in 1791. It shows that the breed descended from a group of English-bred horses whose ancestry can be traced back to three foundation stallions: the Darley Arabian owned by Thomas Darley (1703); the Godolphin Arabian "Barb" owned by Lord Godolphin (1730); and the Byerly Turk owned by Captain Robert Byerly (1683). These three stallions were imported to England from North Africa and the Middle East around the turn of the 17th century and were bred to the strong, locally available native English mares.

The Jockey Club took over the General Stud Book in 1896 and is the official registry for Thoroughbreds. The JC manages one of the most sophisticated computer operations in the country for tracking race results world-wide. Its database holds the names of more than 1.8 million horses in a master pedigree file which trace back to the late 1800's.

According to the pedigree records, the overall foundation stock numbered only 80 horses, with 21 of those contributing a total 80% of the pedigree for modern Thoroughbred horses. Only 10 horses have contributed over 50% of the genes in the current generation of Thoroughbreds and four of those horses appear in the bloodlines of over 30% of modern Thoroughbreds. With such a small gene pool, genetic problems associated with inbreeding are generally expected. However, this does not appear to be the case in the Thoroughbred.

Now, as a result of three centuries of careful selection, Thoroughbred racehorses are the fastest horses in the world over distances of 1-1.75 miles. They have been bred to carry more than 1000 to 1300 pounds of their own body weight over extended distances, galloping at speeds of 35-40 miles per hour, yet still have the agility to respond to changes of pace or direction as dictated by the rider.

The gallop is the most natural gait for the Thoroughbred and the breed canters in a gallop called running. The feet move in a four-beat gait, and before the beat begins again, just for an instant, all four feet are off the ground and the horse is airborne for that single second before he begins the gait pattern again. Patience, training, and breeding can help instill pacing and trotting gaits, as well as other desirable motions.

Thoroughbreds are officially recognized in the colors of bay, black, chestnut, dark bay, dark brown, white, gray, roan, and palomino. The head should be proportional to the rest of the body, with a flat forehead and wide-set intelligent eyes. The head, which is carried relatively low, should sit well on a neck that is longer and lighter than in other breeds. The shoulder should be deep, well-muscled and sloped along the same parallel as that on which the head is carried. When seen from behind or from the front, the legs should be straight and move smoothly in unison through a single plane.

The Thoroughbred is one of the 5 "hot-blooded" horses in terms of temperament, which means they have more sensitivity and energy. But being high-strung gives the Thoroughbreds an edge that helps them compete successfully as race horses. Hot bloods have high intelligence that allows them to be athletic, versatile, and to learn quickly. They have agility and speed and are generally considered spirited and bold. They tend to have long legs and a slim build and are more physically refined than other breeds. Some pedigree lines of Thoroughbred are known to be temperamental, if not hot-headed, while others are equally known for their level-headedness.

All Thoroughbreds are given an official birthday of January 1st to keep the age groups easily defined for racing, regardless of the actual date of birth of the foal. They must be registered with the Jockey Club within a year of the actual birth date and must be DNA tested to prove their parentage. Additionally, a horse must be named by February of its 2-year-old year, but even that can be a challenge, since the owner must submit 6 names and it is the Jockey Club that will decide which name they can have.

In addition to DNA, "night-eyes": or "chestnuts", may be required for identification. These are horny, irregular growths that are found on the inside of a horse's legs. They are just above the knees on the front legs and they are near the rear of the hock on the rear legs. These chestnuts are like human fingerprints since no two horses have been found to have the same set of these growths. Additionally, since they do not change in size or shape throughout the life of an adult horse they are extremely useful in animal identification. The Jockey Club often asks for a set of night-eye photos to assist in the identification of horses that have no white markings or for identifying gray/roans.

An expert on biomechanics of the horse once noted that if there is a limit on the Thoroughbred's performance, it may be on the ability of the horse to remain sound in the face of the tremendous physical stresses of racing.