Change in dog's behaviour,,,
We have 3 dogs, a rottie/chow mix(Chesny-11), a Boxer(Maxine-3), and a Great Dane(Marley-2). This issue has been going on now for a over a year, and dog"behaviorlist's" here have been no help. When we got Maxie, Chesny took the mother role of her they were inseperable. Then we lost our previous reat dane, and got Marley. Maxie took the mother role with Marley and Chesny let her. Everything was fine until Marley was about 7-8 months old(not sure if that has anything to do with it or not), they all got along well. Slept, ate, and played together. Then all of the sudden Maxie turned on Chesny. She started going after Chesny any chance she got. We spererated them completely, Maxie was not just playing, not just saying go away, she was going for maxium damage. With Chesny being so much bigger and stronger it wasn't safe for either to be left together. Nothing in the house changed, it just seemed to start out of nowhere. One day they were best friends the next Maxie wanted to kill Chesny. No other part of Maxie's personality changed, just that. So as of now, Chesny stays in our bedroom with the cat's most of the time, and the other two get their room and the house. I would love to see them all together though, it can be a bit inconnvient having to switch them around all the time, and to make sure that one set is locked up when we leave the house, but the biggest thing is I want them all together. One trainer we went to said that Chesny probably has a terminal illness and Maxie being a pack animal is just trying to kill her off, uhmm no-vet checked out fine other then old age. Vet checked Maxie no health problems there either. Another one told us, they probably just got irratated at each other and because we had seperated them for so long(at that time it had only been 3-4 months) that we could never get them back together and that we were awful parents for doing that, that we should have just let them fight it out, again NO. They were trying to literally kill each other, I would rather deal with the seperation then one be killed. Any thoughts??? As a side note, this has happened with Marley not being and being around the situation.