The problem as I see it is there has been a very sudden and huge change in his environment. My first Dog was a gorgeous Beagle who my Dad bought for me from a Breeder. I was 7 years old and that Beagle bit everyone. My Dad was concerned because I have a younger Brother and 2 younger Sisters. He and my Mom decided to have him euthanized. When my Dad took my Dog to the Vet the Vet suggested Castration. It did improve his biting tendencies and he no longer bit anybody.
The Dog continued to chase Cars and sneak out and race after Squirrels and small animals. He never caught one but his hunting instinct was very strong. I had that Dog from when I was 7 years old and he had a Stroke when I was 23! He was a great Dog and he is why I have a weakness for Hounds.
Having said that, if you do not intend to use your B for breeding, I would have him castrated as soon as possible. The older they are the more difficult it becomes. Be sure he is not a Cryptorchid so the Testicles are entirely removed. Continue giving him tons of affection so he does not feel abandoned by you.
Best of luck!