Horse breaks out in tiny bumps on chest and shoulders after trace clip

I paid a professional to do a trace clip on my 3 1/2 year old warmblood gelding a few weeks ago. Yes, a bit late for a clip but I made a late decision to board him for a couple of months so I could work him through the winter and to get him off the farm for a while as he was really herd-bound to my other three horses.

Shortly after he was clipped, he broke out in small, hard bumps on his chest and shoulders. They didn't seem to bother him much or itch. Now it's been a couple of weeks and his skin has gotten flaky and the remaining hair has fallen out so he has bald patches, which thankfully aren't that noticeable because he's clipped anyway. The bumps are still there, although they aren't as bad where the hair has fallen out.

Has anyone ever had this happen before? I don't usually clip but this guy was so hairy I had to do something as I was spending over an hour drying him out after every ride. But now I feel terrible. Is this some kind of horsey razor rash? Or maybe some type of skin condition transferred from dirty clipper blades?

Hopefully it will resolve as his hair grows back, but right now this isn't making him look very good.

Could just be an allergic reaction to the oil used on the clipper blades. If I clip my guy's face to tidy up, I wipe him down afterwards with some witch hazel. If I don't, he'll get little bumps that get kind of scurfy and lose hair. I've observed the same thing when my horse used to get canola oil. The person feeding would pour the oil in on top of the feed and if my horse's face got in the way, oil got dribbled on his nose and same thing would happen. Where the oil touched, he'd get a scabby or scurfy type spot and the hair would fall out.

My girl was got a full body clip a few weeks ago and had some small bumps on one side of her neck. Not sure why it was only that side, but they looked like very small hives. They went away after a few days. I'm assuming it was just irritation from the oil, but I really have no clue.

My horse's sometimes get those bumps, most likely from the lubrication used on the clipper. Mine don't last long though, only a couple days and they don't scab or lose hair.

My mare gets that every year, and it doesn't have to do with clipping. You just see it when she's clipped. Little lumpy scab thingies that peel away and leave bald spots. It's really random, but it's happened every year. She looks like a moth eaten bearskin rug and will continue to get more and more bald spots. When she starts growing a new coat, the bald spots grow in very dark and her body stays very light and she looks like a buckskin with spots. Then within a week she changes color and becomes a dark bay.

I don't know what it is, but some kind of seasonal thing. If anyone knows how to make this stop, that would be great. I've tried all kinds of things and it doesn't seem to make a difference.

Could be clipper/blade burn. You see it occasionally on clipped dogs.

It also can happen if you clip a dirty horse.

Could be reaction to clipper oil, or scalding from hot clippers.

Thanks everyone for the replies! I guess I'll have to think twice about clipping him next year. The bumps are slowly starting to get a bit better, especially where the hair has fallen out completely. I guess the positive is that you can't really tell unless you look closely because the hair loss is where he is clipped.

I guess it is just the time for random skin issues - his dam just came down with a raging case of scratches, which she has never had before.