The sport of horse racing, which involves humans riding on the backs of spirited horses while they run on dirt tracks, reaches its pinnacle in America’s annual Preakness Stakes. Spectators wear fancy outfits, sip mint juleps, and cheer for their favorite horse. But behind the romanticized facade of racetrack glamour are a world of injuries, drug abuse, gruesome breakdowns, and slaughter.

A horse’s ability to compete in a horse race depends on its age, weight, and training. The most prestigious races are called stakes, and their purses (the monetary sum awarded to the winner) are often the highest of any race. In these contests, each entrant puts up money before the race, and the owner of the winning horse takes home the entire amount—known as a prize purse. The horses compete under a system of handicaps, in which the amount of weight a horse must carry is adjusted for fairness—for example, a two-year-old carries less weight than a three-year-old, and fillies compete with lighter weights than males.

In a steeplechase, which involves jumping over obstacles such as fences and gates, the horse’s strength, agility, and mental alertness are more important than its speed. The steeplechase, which gets its name from the fact that the course is usually over natural terrain in which church steeples are visible from far away, is among the most arduous and dangerous types of horse racing, and a number of horses die each year in such events.

Thoroughbred racehorses have an enormous amount of physical stamina, but they also have a tendency to overexert themselves and get injured. One study found that three thoroughbreds die each day in North America because of catastrophic injuries sustained during a race. Many of these accidents are caused by the horses’ attempts to sprint at speeds too great for their skeletal systems to handle.

Moreover, horses are rushed into racing at an age when their skeletal and muscular systems are not mature enough to withstand the demands of a fast-paced sport. Some trainers use electric shock devices and whips to force the animals to run faster. Even if they survive a race, a racehorse’s career is typically brief. Most are discarded after they lose a few races or become too old to be competitive. A small percentage are sold for breeding purposes, but most end up in slaughterhouses in Canada, Mexico, and Japan, where their flesh is turned into glue, dog food, and other products.

Despite these problems, a few racetracks are making improvements to protect the health and welfare of the horses they house. But many more must rethink their business model to ensure the survival of this once-great sport. In a nation where professional and college team sports have seized the public’s attention, horse racing is losing fan base and revenue. It is also suffering from a shortage of stables, which can be difficult for horses to find and afford.