I've never been too keen on the concept of horse-racing myself. Horse racing wasn't invented for the love of horses, but for gambling, profit, and fancy dress.

Yes, the lucky few racehorses are well treated and lead wonderful lives, but not all horses are Red Rum and Desert Orchid. These horses are broken is as COLTS and FILLIES, with their bones not nearly developed for carrying a person on its back no matter how light it is. They are raced at ages of 2 and can be retired at the age of 4, as someone here mentioned. At four years old a horse has just stopped growing! This is why so many have underdeveloped or wonky joints, as their soft bones were damaged during strenuous exercise.

I don't believe that thoroughbred horses weren't born to run. Horses naturally run together in herds and they have enough stamina to run the races. I see no cruelty in that.

Of course, once the racehorse is of no use anymore that's when problems begin. Most end up in cans of dog and cat food. There isn't a great market for ex-racehorses as they can be hot-headed and it takes a patient and experienced person to retrain them, so they're simply gobbled up by the slaughterhouse.

I've also found it a curious fact that, generally, the racehorses that do lead good lives due to their extensive wins never seem to live over much over 20.

So, I think racing horses as a sport is fine, but, as always, you always get those who overly-exploit in the profits involved in it.