We have a 9 year old yellow lab who has been a wonderful dog and we never had any problems out of him even when we introduced 2 puppies 4 years ago. In the past month or so he has show sudden aggression towards our other male dog. They have gotten into a couple of fights but then will sleep next to each other and everything will be fine. Our lab will be sleeping on the couch or in the dog bed alone and all of a sudden start growling for no reason. I have noticed that he walks into our dining room and just sits in the middle with his back towards us and looking at the wall. Any suggestions as to what may be causing this or how to help resolve the issue? I don't want to try a shock collar since he is so old. Any help is greatly appreciated.
Take the dog to the vet and do a full blood panel including thyroid. Usually when older dogs have a personality change, it's due to medical issues.
Agree w/ yellowbelly. Also have his eyes checked if possible by a specialist. He could have some dementia starting, though 9 seems young for that, so I'd do the bloodwork and eye check to begin with.
WindyCanyon Girls, August 2014