Money!! I just read an article about this (sorry cannot remember where) but the horses today are really pushed/bred into the sport and there bones are not developed like the olden days.

As long as there is money to be made it will never stop. The horse that was put down is just one more of how many who have been as just as many that will be.I agree they are raced way to young and pushed too hard. Oh they get the best of food and then some but once the saddle is on it's survival of the fittest. It's sad.

Yes, as long as people make money doing it, we will have animal racing of any kind.

Horses could be safely raced as 6 year olds, once they have been allowed to mature. However because this would be more expensive and the profits accordingly less, it will never happen.

There is nothing inherently wrong with racing fully mature horses whose bones can handle the stress. Running in a pack is one of the most natural activities for a horse and it requires very little training to get a horse to do this. What is frequently termed training is really conditioning, ie getting a horse's muscles and stamina built up over time. Unfortunately race horses are started too early for conditioning to adequately protect them from injury.

Horses who compete in endurance rides typically compete until they are in their teens, and fatal injuries are exceedingly rare. The endurance race is a grueling test, but because horses must be at least 5 yrs old (if I remember the rules) to compete, a properly conditioned horse with good conformation can expect a lifetime of good health and competition. This is because they are not pushed beyond their limits when they are too young. The reason for this is because, by and large, the owner/riders are not in it primarily for the money.