Unfortunately with rescue dogs it is difficult to know a complete history about them most of the time. When I began to foster Lena we knew she had been abused. :angry: When I startled her awake she came up snapping and growling then got out of the way real quick. After haveing her for six months she no longer reacts this way to being woken up. She knows my intentions are never to harm her. The thing I can't get by is her hatred for men. I won't get into that it isn't what the thread is about. The thing about this is you need to know if your dog's reaction is from fear,dominance,or true aggression. Who ever your dog sees as alpha will usually not get this treatment from him. You may want to incorporate a trainer now to see if you can get this undercontrol. Like someone said ,Euthanasia is not the worst that could happen, being rehomed where someone else could be bitten or even start to abuse the dog because of the bitting, is a worst case scenario.