Mystery Bumps--round ones

[ecileh]

This is going to frustrate some of you because I do not have a lot of information…so…apologies in advance for that. I am sharing everything I know, so if it’s not in here, I don’t have an answer.

Yesterday, a friend on the west coast (Seattle area) showed me a picture of one of the horses at her barn that has mysterious, round, bumps on her neck and flanks. They are truly round–look like raised polka dots of varying size. The mare is not showing signs of itching or discomfort, but was treated for hives with anti-histamines (by a vet). This had no effect.

She was recently body clipped, so they are quite apparent all of a sudden, but my friend rides her for the owner and says some of them were sort of visible before the clip–so it doesn’t seem like they are related to the clip job. The picture I saw was of her side between the stirrup and her gaskin and there were quite a few of them–I would describe her as “covered with them”.

At the moment, there is no oozing or scabbing or the like. Just these raised areas. Her vet is stumped. She was tested for Ringworm as well–negative.

The mare is a draft cross (Perch, I think), grey, and is not new to the property. To the best of my knowledge, nothing has changed in her diet.

I have never seen anything like it–they really are perfectly round–and was wondering if the wisdom of the crowd had. Any thoughts?

[Simkie]

I’ve seen a horse that rolled in an ant hill develop exactly what you describe. Little reactions to the bites.

[mmeqcenter]

I too would assume bug bites without photos or location.

[trubandloki]

If they live where there are bugs right now I would agree that this sounds like a reaction to bugs.

Bugs are hard for me to imagine right now… cold and snowy here.

[ecileh]

Bug bites might be an option…but it is winter in Seattle, too? I honestly don’t know enough about the ecosystem there to know if there are bugs right now. Anyone?

[Seagram]

I ride a horse that has little round bumps around his back area, not a ton, maybe 6-8, slightly smaller than dime sized. He has always had them, they don’t seem to bother him, and we have never been able to figure out what causes them. Vets have looked at them, no ideas what they are. I know this doesn’t help, but just sharing my experience.

[Marla_100]

Also consider ground hornets or bees. I’d be going over the horse’s living quarters with a fine tooth comb to see what’s around.
Does sound like insects of some sort.
I had a young filly get all kinds of bumps and bites from a nesting hawk when she refused to get out of the nesting area. Her pasturemate figured it out real fast, get outta Dodge, but she being a WB (dumblood) never did connect the attacks. DUH.

[oldernewbie]

Oh yeah, I think I know! Eosinophilic inflammation - it’s the body’s reaction to a bug bite or other trauma. The body builds up some protective tissue around the bite. I just had 2 of these lumps removed from my horse and biopsied. He has two other ones which we are going to leave alone now that we know he is prone to them. They are just as you described - round, not inflamed, not painful.

My niece the vet says my horses have weird sh*t and it’s true. Sigh.

Good discussion: https://www.animaldermatologyclinic.com.au/case-studies/azzy-equine

[wsmoak]

For years I thought my horse had the reaction-to-bug-bite type bumps, just a few small round ones on his chest and armpit. But this year I 1. noticed they had gotten larger and 2. finally remembered to ask the vet to look at them and… he says they are probably sarcoids and wants to remove them.

Without photos I can’t tell what kind of lumps we are talking about! And I can’t photograph mine right now for comparison, too much winter fur.

[Calvincrowe]

There are no bugs out in Seattle/Western WA that would leave bites like that on a horse right now. It is winter here. Cool, cloudy, wet, sometimes below freezing and snow. I highly doubt they are insect related.

Without photos, we are all just guessing. I’d have a vet look at them at some point-- doesn’t seem like an emergency of any kind. If the horse has had them for awhile, they aren’t itchy, open or bothering them, a peek by vet at an upcoming regular appointment would be my move.

[joiedevie99]

@Calvincrowe

ut in Seattle/Western WA that would leave bites like that on a horse right now. It is winter here. Cool, cloudy, wet, sometimes below freezing and snow. I highly doubt they are insect related.

Without photos, we are all just guessing. I’d have a vet look at them at some point-- doesn’t seem like an emergency of any kind. If the horse has had them for awhile, they aren’t itchy, open or bothering them, a peek by

I have a horse with these too. 5 of them on his back. Vet called then collagen granulomas, and said they were likely the result of irritation/friction. She said we could ignore them as long as they remained asymptomatic, or inject with steroids. We elected to inject.

[ecileh]

Thanks, everyone, for your thoughts! I do not have the picture, but will see if she will share it with me. We were zooming when she showed me, so I don’t have a copy.

[oldernewbie]

These bumps don’t come from recent bug bites! They build up over time. I am sure the ones on my horse are from the summer. Just took me a while to notice them and to get appt with vet to have taken off etc.

The second possible diagnosis was sarcoid so I really wanted to have them biopsied. Glad they were not that or anything else.

[AllTheCarrots]

Maybe rain rot?

[frugalannie]

I’m sure this’ll sound ridiculous to many, but if there is Lyme Disease in that area, get the horse tested and treated if necessary.

We live in Lyme central here. Sometimes horses with idiopathic bumps turn out to have Lyme, that apparently sequesters in the dermis. I’ve had two over the years. One that had a bump distribution rather like the one you describe. The one I’m currently dealing with just has a few bumps under the saddle area. I’m hoping we caught them before they calcify. If we did they’ll eventually go away, and they have gotten noticeably smaller so I’m hopeful.

[ecileh]

@AllTheCarrots

Maybe rain rot?

Definitely not rain rot. The bumps are perfectly round–like discs–and there is no scabbing.

[Brown_Derby]

New blanket or bedding? Any soap residue, scurf/dried sweat or debris under the blanket?

It’s a good sign IMO that there is no oozing or scabbing.

[Jackie_Cochran]

I do not know if this is the same thing, but here goes.

My very feed efficient Arabs/half-Arabs would sometimes get these little bumps on them, no crust, just sitting there, no itchiness or sign of skin trauma or bug bites (as in the middle of winter sometimes). An older horseperson told me they were “protein bumps” and to reduce the protein in my horse’s ration.

After that I always reduced the protein load (alfalfa/alfalfa pellets) when they reappeared and those darn bumps would go away, until the next time the horse got too much protein.

[SuzieQNutter]

@Seagram

I ride a horse that has little round bumps around his back area, not a ton, maybe 6-8, slightly smaller than dime sized. He has always had them, they don’t seem to bother him, and we have never been able to figure out what causes them. Vets have looked at them, no ideas what they are. I know this doesn’t help, but just sharing my experience.

I am on the other side of the world.

I have been taught to remove the saddle cloth, put it back on for the back to cool down slower, and then remove.

When we moved into Summer and her Summer coat she had hair missing. I asked her former owner and she said that she had had lumps surgically removed.

When someone else was tacking and untacking for me. The lumps reappeared. I was told I would have to get them surgically removed.

I did 2 things. One I made sure the saddlecloth was replaced. Two I sprayed daily with permoxin.

I don’t know which worked, or both, but the lumps did disappear.