Ok. We just noticed that Cocoa has some scabs on the top part of his tail close to the base (near the back). It's not bloody, raw, red or infected looking. It looks kind of like a combination of dry skin and possibly some oily residue or puss (it's got a greenish/yellow tint to the dried scab). He nips the top of his butt/base of his tail sometimes. Not alot, but very fervently when he does it. Could it be that fleas congregate there and bug him so he nips at them? We've sprayed the house, washed them with flea shampoo, bleach/water mix *supposed to kill fleas immediately*, sprayed them with Hartz 3 in 1 Dog Spray AND *until last month or two* put Flea drops down their back (advantix? I think). The yard has also been bug sprayed. What is the deal???