One of my ponies is rubbing his neck, shoulder and chest to the point of where it looks shaved. He has been doing it on and off all winter, and has a very thick coat. I haven't caught him in the act, there were a few scabs and a bit of dandruff in a few spots. I put some fungicide on it, to make sure it wasn't ring worm or anything like that, but it hasn't stopped him rubbing. Any ideas what it could be. Bathing is out of the question because it's very cold here right now.