The foot.
Topaz' left foot has been bothering him so he has licked the fur completely off between 2 of his little dog toes. So we've been attempting to treat it with different methods, everything from Gold Bond to homepathic remedies. Finally I think we're onto something: he's on an elimination diet of pork and vegetables to see if it's a food allergen. But the colloidal silver wash and dousing of Gold Bond powder with a boot over the foot seems to do the trick, at least to stop him from worrying it.