I have 2 dogs, one a 2 year old male boxer, and the other is a three year old shepherd/doberman.
They get along quite well, but sometimes when a bone is involved one of them will try to stand over top of the other one to show dominance with the bone in their mouth. A few times over the years I've had to get involved with them, but it has never gotten too serious to the point where either one was hurt. I think it's because you have all males, and if none of them are fixed then they will all fight to be the most dominant. I'm sure the 2 being deaf does not help the situation as they are unable to communicate fully with the other dog.
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