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I have 3 dogs. Ruby, a 4 yr old springer spaniel bitch and Jack and George, 2 male 1 yr old JRT litter-mates. The dogs generally get on fine with each other, play-fighting or sleeping together. However, George, the smallest of the JRTs is very aggressive towards other dogs when he is on the leash. At home he a is very quiet, affectionate dog, even appearing to be the peace-maker when things start getting rough, and he doesn't seem to be as aggressive when outside if he is running free. My question is this. On at least 3 occasions George has grabbed another dog by the nose hard enough to draw blood. No growling, just grab and hold. It's not like fighting, just like holding on for grim death. Is he doing this out of fear in an attempt to prevent the other dog biting him? What can I do to arrest this behaviour before I end up in trouble? Should I invest in a muzzle?
I did take him to puppy classes when he was 4 months old but it didn't last long as one of the trainers hit George when he attacked another puppy.