Ask a veterinarian - Dog
It is normal for a dog to chase its tail from time to time for fun. However, if a dog chases its tail intensely for several minutes, or bites holes through the skin it is not normal and can be a result of: the dog being painful there, a tumour, problems with the lower back or compulsive behaviour problems. There is no cause found or treatment available for dogs that compulsively chase their tails. If you suspect that your dog is chasing its tail due to a compulsive behavioural problem you should consult a veterinarian first to rule out any underlying physical causes.