After enduring 8 months of treatment marked with several setbacks, Kentucky Dirby winner Barbaro was finally put to death today. To refresh your memory, or if you haven't seen it, last year at the Preakness Stakes race, this happened:
As you saw, Barbaro shattered his right rear leg and his momentum forced him to even run on it for a considerable distance, and that must have been painful.
Moreover, in a heart-touching show of horsemanship, Barbaro's jockey got off of him right away and put his body under Barbaro's shoulder.
That's important to note because it could be one of the reasons Barbaro survived for 8 months. You see, usually rear leg fractures are fatal. Additionally, a horse's blood circulation hinges primarily upon the even distribution of weight over his 4 legs. If that distribution is disturbed, blood ceases to reach some parts of the body, and if those were critical parts, it could cause imminent death. Therefore, the jockey's body helped compensate for the lack of support created by the broken leg and eventually saved his life back then.
Being passionate about everything to do with horses, I've always hated horse racing. First of all, compared to all other equestrian activities (jumping, polo, dressage, fox hunting, etc.), it's the least creative (just go fast!). Secondly, the severity of the injuries sustained by the horse or the rider is extremely high. Third and most importantly, it's become a dirty business.
Because of the amount of betting money involved, horse owners and breeders are "custom-making" horses to win races, where the horse's body structure is manipulated badly through mix-breeding. The two most important physical factors that make a great racing horse by industry standards are minimal bone mass (to minimize the weight the horse has to carry) and maximum muscle power (to maximize speed). For that, breeders have been mixing all kinds of breeds to produce horses that are, more than anything else, like octopuses. The result is this: in recent history, horses came to have the highest mortality-per-injury rate amongst all mammals (including humans), sadly.
Barbaro was a great, well-trained horse. Unfortunately he died today because he "took a bad step," not "collided" or "tripped," he just took a bad step. That's what happens when there's not much bone structure supporting over 1000 lbs of body weight.