As with all aggression problems, I would seek professional advice, especially when a dog has bitten. Attempting to address this problem yourself, may do more harm than good.

I would strongly suggest that you speak with your vet, who will refer you to their chosen dog behaviourist. If he is insured, you should only need to pay the access fee.

Good luck and please give him a chance. The only other option would be euthanasia, and his aggression may even be a medical problem.

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