Rain rot or something else?

So, last night I was just messing around with Ice while I was tacking him up, just rubbing his stomach and stuff while I was tightening his girth when I noticed about two or three inches behind where his girth is there was some kind of scab formation. It was maybe three inches long, and it was a single straight line. It was right at the apex of his ribs--basically the dead center of his stomach. Obviously it was kind of hard to see, since he has his winter coat and I can't exactly get down under there to look. On top of that it was dark, lol. But I did manage to get a flashlight and get the best look I could. The scab kind of looked like it had a reddish tinge to it, but I can't be too sure. I'll try and get pictures of it, but I can't promise anything.

So does rain rot usually show up in clusters, or can it show up in a long line like that? The scab did feel big, like it was layers, but it wasn't very flaky. It hasn't been ridiculously wet here, and when I give him a bath I let him graze and sun dry and I always make sure to scrape him really well.

Im guessing its not rain rot. It doesnt sound like it at all. Personally, to me it sounds like the girth may have slipped back and rubbed a little, or your horse rubbed against something that caused it.

I've seen rain rot form in the apex of the belly before. One of my mares has a "line" (of muscle I suppose) that goes from her belly button almost to where the girth sits, and opposite she has a line going from her belly button to her teats. It's just how she is. She does get rain rot there from time to time.

I'd clean it up with some Betadine and see if it persists.

The red in color thing is kind of weird though...it could be due to the type of dirt you've got around you.

Well, here in Florida we have sand....so I wouldn't expect it to be red unless he was bleeding or something. I'm going out there today to get his feet trimmed up, so I'll take pictures then

Yeah, you might want to get your vet out if it is that big and deep and funny colored... you never know could be harmless but better safe than sorry...

Well, its doesn't feel very deep, its just layered....but at any rate, I had my BO confirm it is rain rot, their shetland pony has it in the same place as well. He also has another little line where his hip bone sticks out, and its only on his left side. I'm treating it with a home made combo that my BO made, and I'm contemplating bathing him with some Dawn.