I had sister poodles, they'd also get into fights. For the most part it wad just standing on their hind legs, growling, and teeth bared, sometimes it was worse.
They did it until the end.
If they had chews they'd also try to steal from each other, some of the fights happened because of this.
I'm not sure if you can train them to stop. If you really want to give them chews I'd put them in crates or seperate rooms. |