Sounds like your doing a good job with him so far. Well I have a few questions. How long have you had him? Was he with other horses before and/or now? Also can you bathe him?
Ok, if he was or is with other horses the bare spots on his back could be from other horses biting at him, this will expecialy happen if he is at the bottom of the pecking order. My youngest horse had a lot of bare spots from the other 3 biting her.
The bare spots could be from rain rot. Check out this site http://www.equusite.com/articles/hea...hRainRot.shtml
You might have to copy and paste it. There is an awsome product called Shapleys M-T-G "Mane & Tail conditioner, skin treatment & hair growth producer. Can produce tail growth of over three inches a month. Dermatitis treatment recommended by veterinarians for a variety of skin problems." This will help with almost any type of fungus. It will also just help regrow the hair. So it will work on the bare spots, if they are bite marks or a fungus. It will also help with the rubbing area on the chest grow back. Im not sure where you are but I get it at Tractor Supply Co store.
If you still have question just post and ill try to get back with you asap. Good luck![/url]