I've been writing these past few weeks about horrendous and fatal equine accidents in the sport of three-day eventing. I own seven hunter/jumper show horses and maintain my own 40-acre horse farm.
Second, the trend toward breeding thinner-boned thoroughbreds should be banned immediately. Horses are bred for speed, which often means thin-boned legs. The thinner the bone, the more easily it breaks. Horses with broken or fractured legs don't always have to be "euthanized" (I prefer the term slaughter, since that's what it really is). They're often killed when owners decline the alternatives: huge veterinary or board bills to keep injured horses standing in hoists for a year or more to allow their bones to heal.