Dog Biting Tail No Fleas. Fleas are small bugs that can attach themselves to dogs and cause discomfort. When your dog keeps biting his bum and tail, it could be a bad habit that he has picked up.
Those nasty little buggers infiltrate our nightmares if we even spot just one! Tail chewing may be a sign that your dog has fleas. Fleas are small bugs that can attach themselves to dogs and cause discomfort.