tug-of-war

Question
Our saint bernard/collie mix puppy joined the family about three weeks ago.  We started playing tug-of-war with him, not thinking anything of it.  Recently I have noticed that this game seems to have sparked an aggressive spark in him.  I have been trying to avoid playing tug-of-war with him since then, but that seems to be all he wants to do.  Whenever I try to interest him in fetch, he quickly becomes disinterested in retrieving the toy and changes his focus back to fighting over it.  Any suggestions?

Thanks,
Bre

Answer
Generally "tug" doesn't create aggression. There should be some rules for it, though. You say when the game starts,  you say when it ends, and if you feel teeth on skin (even accidently) the game is over. I'd ask him to give me an obedience behavior as a request to play tug. If he wants to fight over fetched toys, start by having a second toy to show him so he'll drop the first one. If he doesn't want to give it up, the game's over, you turn and walk away (which is the LAST thing he really wants) If you try to wrest it away, it becomes tug and he's rewarded for that behavior. Have you looked into a good puppy class for him yet? Sandy Case MEd CPDT www.positivelycanine.com