Honestly what a crock of ..... ! So a trainer races his horse every 7 days, he comes home from the race and gives his horse injectable bute (6 day withdrawal). He gets tested his next start (7 days later) and nothing comes up, because THERE IS NOTHING IN HIS SYSTEM. So these trainers, who follow withdrawal periods, are using "performance enhancing drugs"? Just because a stable gets a vet out weekly, or whatever, even daily, does not mean they are racing their horses on performance enhancing drugs! If it's not in their system raceday, how can it be performance enhancing? Following withdrawal periods is not "trying to prevent a slip-up" (ie somehow trying to gain an edge in the horse's following race). Horses CAN race week in week out, even having hard runs everytime out, without any help. You just don't do much with them in between races to keep them fresh. There is a difference between therapeutic and performance enhancing drugs.