Horses have been a part of our world for thousands of years. We’ve used them to pull buggies and carriages, fight wars, and, since the mid-1700s, pitted them against each other in races. On a racetrack, humans perched on their backs compel horses with a whip to breakneck speed. It’s a brutal sport that, in its best moments, can produce spectacular feats of equine brilliance. But despite the showy spectacle, horse racing is a business that exploits animals in many ways, including forcing them to run too much and take illegal drugs. It’s no wonder hundreds of horses die on and off the track every year.

A horse’s long torso and spindly legs make them vulnerable to injury. Breeding them to reach full maturity—when their bones have stopped growing and the growth plates in their spines fuse—takes up to 18 months, but they’re raced as young as 2. During that time, they’re pushed beyond their limits, and given cocktails of legal and illegal drugs intended to mask injuries and artificially enhance performance. Many of these medications cause horses to bleed from their lungs, a condition called exercise-induced pulmonary hemorrhage.

Until recently, drug limits and rules varied widely from state to state. Fines, which often amounted to a few hundred dollars, were no deterrent to trainers who violated the rules by using a wide array of banned substances, sometimes even in varying combinations. Even when suspended from one racetrack, trainers could continue to compete at other tracks, claiming their share of the prize money.

The sport of horse racing has long been a lucrative enterprise for the wealthy. It is a multibillion-dollar industry that attracts millions of spectators, who bet on the winner and are often entertained by the showmanship of jockeys, owners, and trainers. But the sport is also a violent and exploitative business that, in recent years, has been rocked by the deaths of several horses and the public euthanasia of a beloved horse, Havnameltdown.

Flat-course horse racing is the most popular form of the sport, but there are a host of other events, from the prestigious Prix de l’Arc de Triomphe in France to the Melbourne Cup in Australia, and even grueling marathons like the Grand National in England. There are also handicap races, in which horses of varying ability compete against each other. Generally, the faster horses carry the heavier weights. During handicap races, the jockeys try to balance a horse’s natural speed and stamina with their own skill in handling a race. They place bets on the horse they think will win and hope to gain a profit by adding up the amount won on each wager, or “take.” The winner is the horse with the highest total payout, or “takes.” The remaining horses must divide the take evenly among themselves. A portion of the take is paid to the horse’s owner, with the rest distributed among the top finishers. The race is then broadcast around the world.