Thanks for the response. My husband made this post, which is why the post sounds like I'm talking to people who don't recognize me, haha.
Anyway, Sage/Samus (the aggressor) is doing a lot better. We are squirting her when she growls and are having her wear a muzzle.
I don't have a problem with the muzzle part, but why would you take away her "early warning system" by squirting her when she growls? Also, why would you want her to associate the presence of the other dog with being squirted? My inclination would be to feed her some squeeze cheese through that muzzle when the object of her dismay appears, and I would stop feeding when he disappears. That might change her opinion of the smaller dog over the long haul.
She doesn't like the muzzle, but she bit Tojo really hard twice, and I think every time he gets bitten the situation gets worse. Tojo hid in the bedroom all day after she bit him. She hasn't made a lunge at him or growled all yesterday, so I think she is learning. Or, it could be that he is learning - that his home is no longer a safe place to be. I don't understand why you would have adopted a dog that someone described as dog aggressive, and subjected your resident dogs to that behavior. Seems to me that the dog might have done better in a home where she is an only dog. Not to say that this cannot work, if the description of her getting better when she is used to the dogs is true. But, personally, I would maybe a adopt a dog that argues with my resident dogs, but not one that "bites hard", and makes them afraid or unhappy on a more or less permanent basis. JMHO, and not trying to offend you - perhaps her situation was such that you needed to get her out of the situation she was in.
Your post gave me hope. My honest feeling is that they will adjust and learn to be friends. Sage/Samus has a history of dog aggression, but her previous owner tells me she does well with other dogs if introduced slowly, so I think it will just take time. For your sake, I hope that you are right, and that there will be no further incidents. Is the smaller dog a male or female, and what are the dogs' ages?
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