It started as multiple, small (1/2 inch in diameter) crusty scabs. She was very, very itchy, and I went over her and looked at every spot, and the hair was falling out in chunks. I bought so MTG the next day and started to apply that. She originally had them over the entire length of her back, loin and croup. The ones on her croup have cleared up, but the ones on her withers and back got worse before getting better. The hair is beginning to grow back but there are huge (the biggest one is probably 2 1/2 inches in diameter) bald patches because she is rubbing SO incessantly. I thought it was rain rot, but I didn't think rain rot was this itchy. Is it? She's very itchy. The bald patches don't seem to hurt her at all, in fact she loves them touched and stretches out her neck and turns her head sideways, obviously really liking it scratched. I let her roll in the sand a couple times and she would lay there and roll for, no joke, 10 minutes in the ground. She's been wormed, had a fecal done 2 weeks ago and it came back negative. She has ample shelter as well as an outdoor run. Any thoughts? Should I not ride her? They don't hurt.