Aggressive towards other male dog in our home

by Rebecca
(Stanwood, WA)

We just adopted a JRT from a local shelter. He is appx. 6 and was neutered at the shelter. We have had him only 4 days. I love him. My husband isn't crazy about him. We have a neutered male Sheltie around the same age as the Jack. The Jack stands ridgid and eggs him on for a battle. The Jack loses all the time. I bought both the males a muzzle and let them have at it. The Jack showed minimal submission for 4 hours, then he was back to his ridgid stance, and I dare you attitude. Will time make matters better or worse?? I don't think the Sheltie will put up with being bullied. He is not the aggressor, and I really do think the Sheltie wants to be friends. HELP because like you, the Jack stole my heart.