Reptile & Amphibian Forums

my horsey has quite a problem. his skin is coming off in super-sized flakes, maybe more like scales. he's also missing a few patches of hair on his face. he's got a few places on his neck and legs that have something like a weird dark gray crust too, and if i curry comb them they come out, but it takes foreeeeeeeeeeever and a day, and still doesn't come out very thoroughly. has anyone else ever heard of this?
another problem he has are these funny open sores he's getting on the back of his feet. i'm really worried about this, what do you guys think these things could be?

Is he outside most of the time in bad weather? Rain rot and scratches?