the few times when I own a pit bull I never turn him loose in the back yard with the curs unless I am supervising them the whole time...but I will let the curs run together in the back yard with minimal supervision...because I know I can usually break the curs up pretty quick...
Smart! imo bulldogs should never be left unsupervised with any dogs period. I believe you have to treat them like a loaded gun because of the potential damage they can cause. Even if another dog starts it with them and you are not around to stop them, bad news for the other dog. I believe prevention is key, keep them kept properly and you will be just fine.
