But then I recommend that all be muzzled when running. I never used to.. but over the years of coursing have totally changed my mind. But not because dogs might be nasty… If you start out your dogs with a muzzle, they begin to associate the muzzle with coursing and know when that goes on they are going to "chase" the bunny. I would prefer that it was "required" for all hounds to run muzzled like it is for Oval/Straight line.