I have a horse in a stable 2 miles out of town. I try to see him everyday. Recently I went out on a Sunday Night. I didn't have to chance to go out any on that Monday, but on Tuesday I went to go see him. I was putting on his halter when I noticed a huge bare spot on his chin that wasn't there before. It has a couple scabs on it to. I posted a pic below. After looking around I found very similar, but smaller spots all around his body. Is this a skin condition? And if so, how did it develop so quickly? (I would have noticed it when I was brushing him if it was there Sunday) He is out in pasture, and has been since I bought him 4 months ago. It just started getting cold here, and we had snow the morning I found the bare patches. It has been raining off and on as well. At this point I'm still deciding if I should talk to my vet or not. The spots do not seem irritated and he doesn't show any response to me poking around on them. I don't even see scabs on most of the spots, just a couple little scabs on his chin.
Spot on chin:
One of the spots on his side: