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How to stop dogs from biting
Keep a puppy with its mother and siblings for ten weeks.
Let your dog's original family shoulder some of the teaching load before your family takes over the job.
For dogs, as with other animals including humans, an important function of play is instruction.
Puppies use yelps of pain and refusal to keep playing to instruct each other about the differences between playful mouthing and painful biting. Mothers likewise play an important instructive role in the formative weeks of a puppy's life, one that is hard to replicate or replace.