My horse has little clusters of bumps on his back, his belly and his elbows. They are the same as those tiny scab-like bumps you sometimes see on a horse's legs. You can scratch them off with your fingernail.
I have been thoroughly washing them (today with vinegar and water) and I have been putting on various different creams, including Hibitaine and corona. The creams do help, but then new ones come up in a different part of his body. They seem to be very itchy, as when I curry the areas, he practically turns his head upside down with relief.
As an aside, it is extremely hot, humid and buggy here.
Ask your vet if it may be "warble flies". Your description sort of sounds like what I saw decades ago and that is what the horsewomen called them. Treated, of course, in consultation with your vet, you may have to apply chemical (organo-phosphate) insecticide topically and anything else your vet recommends systemically. The flies of the warbles either are or are closely related to the bot egg fly.
Sounds rather rain-rot'ish, our younger mare used to get that under winter blankets, so it would be conceivable that it could develop in humid conditions (she sure wasn't wet!).
Other than getting a vet opinion, I'd scrub with hibitane (surgical scrub of chlor-hexidine). And then spray with Vetericin, which is inocuous to the horse, but will get the bacteria or fungus. Best of luck!!
how old is your horse??? and one of the horses at our barn has the exact same thing in the exact same place.... he's 28 and pretty skinny so his owner is thinking that these are somehow related to sweat so what we have done is, instead of a sliding door to his stall we have a single rope across and a fan blowing in his stall. we are picking them off everyday :)
I think it is rain rot-ish. I have been washing him and putting him out to dry in the sun after riding, then rubbing in Hibitaine lotion. I also spray him with Listerine after bathing (which nicely cures sweet itch in the dock).
Another horse in our barn has a really bad case of it. It has been impossibly hot and I wonder if all this started with the unrelenting heat.
In any case, I also have this blue spray for wounds. It treats and dries up skin lesions. I was thinking of using that. So my choice is lotion that keeps the area soft while getting rid of the bacteria or a drying spray that gets rid of the bacteria but dries up the area. Any additional thoughts?
sounds like it might be onchocerca , its a parasite that infects the skin. Ivermectin will kill the microfilariae in the skin leasions. It is transmitted horse to horse by midges, so keep these to a min will help control furture outbreacks.
Decades ago (1970's?) my horse had a weird skin condition, the skin on his right flank had deep wrinkles. The vet biopsied him and told me my horse was infected with onchocerca. The vet treated him intraveneously once or twice I think, and it took a while to get the whole flask into my horse through the IV needle.
The best thing I've found against rain rot/fungus is a pet slicker "brush", with lots and lots of little wire teeth. Ticklish horses do not particularly like the slicker brush, on them I started off trying to make sure the teeth did not hit the skin. On the other hand my less sensitive horse LOVED the slicker brush, the harder the better. Best to start off really light, the increase the pressure over a few days. During the rainy season/winter I use the slicker brush lightly once a week as a preventive on a very sensitive ancient mare that is in the pasture 24/7/365 and groomed only once a week. It prevents the fungus from building up in her coat.