3 month old mastiff cross showing aggression
(saskatoon, sk, Canada)
we got our puppy a week ago and i took him for a walk with his (11 year old) great dane brother yesterday expecting the field to be empty. there were 3 dogs of various sizes that came up quite suddenly, and my guy just about lost his head, jumping, lunging, barking loudly and wildly, and basicly frothing at the mouth. he was on lead, so I kept him with me, but if i hadnt I'm quite sure he would have tried to bite.
as he will be large, obvioulsy this can't continue. Outside of socializing, what should i do?