A horse race is a contest between competing thoroughbreds, usually run on an oval track. The races are held by the thousands, in countries around the world. The sport is regulated, with strict rules and a high cost of ownership. Most of the horses are bred, raised, and trained by professional breeders, owners, trainers, and jockeys. They are often subjected to harsh training practices, drug use, and injury. The horses also face a high risk of death and slaughter.

In the 1790s, racing began to evolve into a more formalized industry with organized races and betting. The sport is characterized by intense competition between horse and rider, with wagers on individual horses and on the overall winner of the race. Many of these races are graded, meaning they have minimum purse requirements, and a variety of weight allowances for horses based on their past performances.

The sport has long been a source of controversy, largely due to allegations of shady betting and gambling. The industry has also been accused of drug abuse, overbreeding, and cruel training and handling practices. Many animal rights groups have campaigned for the sport to be banned, but the movement has failed to gain traction. In recent years, the racing industry has made improvements in safety, horse welfare, and the quality of horses.

When a horse is injured or killed while racing, it is considered a catastrophe for the industry and a loss of public confidence in the sport. Horses have been injured in a wide range of accidents, including breakdowns, accidents while being shipped to and from the track, and injuries sustained during training. The most common injury is a fractured leg.

Racehorses’ lower legs take a beating while they run, particularly on oval tracks. The impact causes strain on ligaments, tendons, and joints. Mongolian Groom, the horse that died at Santa Anita in 2019, was severely lame on his left hind leg. His trainer, Nick Alexander, said he did not have time to nurse him back to health before his next race. He said he lost faith in the track surface and could not relax his horses at Santa Anita because of the danger there.

Several types of race are held worldwide, but the most famous are the Prix de l’Arc de Triomphe and the Kentucky Derby in the United States, and the Melbourne Cup and Caulfield Cup in Australia, the Gran Premio Internacional Carlos Pellegrini in Argentina, and the Durban July in South Africa. Some of the most important flat races in Europe are the Champion Stakes and Arc de Triomphe in France, the Oaks and Epsom in England, and the Arima Memorial and Wellington Cup in Japan.

Horses are injected with a diuretic called Lasix before every race, and it is noted on the official racing form with a bold-face “L.” The drug prevents pulmonary bleeding, which hard running can cause in a small number of horses. But the practice is controversial because it has been linked to a rise in the number of horses that die during and after races.