well i have run racing and courcing events at shows for years and we ALWAYS muzzle and always make sure any dog that causes problems to other dogs are banned but i find the biggest problem when running the racing is normally from people watching with their dogs and not being able to keep them under control .. not fair on a dog racing if a loose dog without a muzzle gets away from its owner during a race mind i have found a hefty fine normally makes them hold onto their dogs better he he