To be registered as a Thoroughbred, a foal must be the product of a “live cover,” meaning a witnessed natural mating of a stallion and a mare. Though artificial insemination and embryo transfer are possible and common in other horse breeds, it is banned with Thoroughbreds. The population of the breed is thereby controlled, assuring a high monetary value for the horses in the process. Because each foal is assigned an official birth date of January 1, to facilitate the age groups that define Thoroughbred races, it is important that mares foal as early as possible in the calendar year. This assures maximum development time for the foal before training and racing.

The guiding principle for breeding winning racehorses has always been best expressed as “breed the best to the best and hope for the best.” The performance of a breeding horse’s progeny is the real test, but, for horses untried at stud, the qualifications are pedigree, racing ability, and physical conformation. What breeders learned early in the history of horse racing is that crossing bloodlines can potentially overcome flaws in horses. If, for example, one breed is known for stamina and another known for speed, interbreeding the two might result in a healthy mix of both qualities in their offspring.

Racecourses

The ownership of racetracks ranges from complete state control, in which case the national government may own the tracks and horses and employ trainers, jockeys, grooms, and other necessary personnel, to complete private enterprise, as in most of the United States, where tracks are privately owned and operated for profit, as are the horses, and trainers and jockeys are independent contractors. In-between conditions include government ownership of tracks and in some cases horses, which are leased, and nonprofit privately owned tracks, as in Australia and the New York Racing Association.

Racetrack stands range from the elegant (Longchamp in France, Ascot in England) to the modest and purely functional (Cologne, the Curragh in Ireland). The same variety is true of the saddling area, the paddock. Most European and other racing surfaces are grass; in North and South America the common surface is dirt, though grass became increasingly popular in the 20th century. Synthetic racing surfaces, which routinely drain better than natural surfaces and cause fewer fatal injuries, were increasingly installed at racetracks during the 21st century. Racing takes place mainly in the daytime.

Older racetracks, mainly European, conform to natural terrain, accommodations for spectators having been added later. The course at Newmarket, for example, can accommodate a race of 2.25 miles (3.6 km) with a gentle change of direction of less than 90 degrees, but spectators cannot see all the race. Newer tracks are elliptical 1-mile- (1.6-km-) long tracks.

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Racing procedure

The eligibility of racers is checked the day before they are raced. Before the race, jockeys weigh out and report to the paddock for instructions by trainers and mount up, the identity of the horses having been checked. Horses and riders proceed to the track in a parade to the post for the stewards’ (race officials’) inspection and a brief warm-up gallop. Horses are almost universally started from electrically operated starting gates, the horses being walked or led into their stalls prior to the start of the race. The starter actuates the upward swing of the barrier from the stalls when all are in place. During the race, stewards and patrol judges are alert for racing violations, supplemented by a motion-picture patrol. The finish is photographed by a special camera, and, when the race is close, the picture is awaited before winners are announced. The race’s result does not become official until the jockeys have weighed in and the riders of horses that finished in the money are certified to have carried the proper weight. At weighing in, a jockey, owner, or trainer may claim foul against a horse that interfered with his mount. The judgment of the stewards may result in a horse being lowered in order of finish from first to last. The stewards declare the race official, and then payoffs are flashed on the totalizator. Postrace urine tests are made of winning horses and a sample of the field, and if results show the presence of forbidden substances, the results may be changed on payment of purses but not on bets.

Most time records are clustered in North America, where speed has long been a desideratum. Races in the United States are timed to 1/5 of a second, as opposed to 1/100 of a second elsewhere.

Racing silks

Colourful racing silks are a familiar element of horse racing, and their introduction dates to the formal organization of the sport in the 18th century. Though they primarily serve an aesthetic purpose in the modern sport, their original use in racing was to allow spectators to distinguish one horse from another during races in an age before television and public-address systems. To this day horse owners must register a unique pattern and set of colours (worn on the jockey’s jacket and helmet cover) with a regulatory board.

Racing strategy

The earliest American racecourses were typically straight quarter-mile sprints. For these short distances, American jockeys developed a style of riding involving a short stirrup and a crouching posture—this “American seat” eventually became standard worldwide for all distances. As longer, elliptical racetracks were built in New York and throughout the South, a greater onus was placed on jockeys to pace their horses. Because Thoroughbred horses are capable of running only about a quarter of a mile at top speed, determining what pace to set and when to unleash this burst of speed is crucial to winning. The American jockey Isaac Murphy was famous in the 1880s and ’90s for his “grandstand finishes.”

Training

The training of racehorses, simply expressed, is maintaining a horse in the best condition to run. Exercise and feeding programs and knowledge of the individual horse are factors involved. A good trainer selects a jockey who suits the horse and, perhaps more important, enters the horse in suitable races. A trainer of a horse for a classic race not only must develop the horse into peak condition but must time the development so that the horse reaches its peak on a certain day, which is the most difficult art of all.