Aggression & Biting

We've had our Jack Russel "Snickers" since he was 8 weeks old, he will be a year old the end of April 2003. We got him from my husband's cousin who has bred her Jack about 3 times now. We are having a big problem with him being very aggresive towards people he doesn't know, other dogs and he is very possesive of his toys and sometimes he bites. He bit a friend of mine the other day for no reason at all. She bent down to kiss his head (which she has done lots of times before) and he sounded very visious and bit her just under her chin. Didn't break the skin but left a mark. We have to muzzle him to take him to the vet because he gets very visious with people he doesn't know. I'm not sure how to teach him not to be this way. I am scared that he might really bite someone. Other than this behavior he is an absolutly great dog and my 3 daughters adore him very much. Can anyone help me please??????

• Re: Aggression & Biting Feb 28 (0)