This is one of the reasons that the YTCA recommends pups stay with their mom a MINIUM of 12 weeks, the mom teaches inhibition of the biting reflex. Since his birth mother couldn't teach him, you as his new mom will have to teach it. Don't forget those gums of his hurt and he does need chewing sticks and toys. Some people say if he bites you, let out a yelp, set him down and give him a chewing stick/toy. It's probably best to always have some sort of thing for him to chew on when you pick him up. Something like this will a gel you can freeze works well.
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