What plant or bug is causing these hives/scalding and how do I get rid of it?

[fordtraktor]

My horse came in about 10 days ago with a swollen chest and hives all over his chest/between his front legs. The hives have turned to scald and his whole chest is peeling. It looks terrible! Of course we had a show this weekend and he was a trooper about being ridden anyway, but day 3 he got grumpy and I just retired as I figured his girth was bothering it.

I first used SWAT and then silver honey spray I bought at the show. Neither are helping at all, except to keep bugs off it so it doesn’t get worse. Pics attached. And a pic of him being beautiful so you can see he isn’t a total trashfire:

[JB]

Possibly a nest of ants or ticks.

[Marla_000]

What brand of fly spray are you using?
I had a similar problem. Had just bought a new gallon of Endure at TSC when this showed up.
Last month the new gallon, also from TSC seemed diluted and ineffective with the flies.
Years ago when I boarded, had a BO who would randomly grab a boarder’s fly spray and pour a bunch into her fly spray bottle, then take the boarder’s fly spray into the bathroom and fill up with water. I saw her do this
So sometimes I’ve wondered if people in the stores do it too.

[Texarkana]

@Marla_000

What brand of fly spray are you using?

I was going to ask about fly spray, too. Have you changed it recently or been using a different brand? Usually that peeling-like reaction is to fly spray.

Bug or plant reactions are usually more hive-like or rainrot-like.

[JB]

If it was just the peeling, I’d totally blame a new, or heavier than normal application of a fly spray. It often does that on thinner skinned areas like the chest/shoulders/neck

Since she said “hives have turned to scald” it seems like it started with lots of little bumps. I couldn’t say fly spray wouldn’t do that, it just seems more likely to have been some insect involvement

[fordtraktor]

I have been using the black ultrashield all summer.

It started out as swelling and hives, then turned into this peeling. There is a spot by his withers that is almost rain rot like, no peeling there but bumps. They aren’t crusty, but they are hard. Impossible to photograph! You can see one in the girth area photo in a skin crack. Poor dude!

[fordtraktor]

Adding, at the top of his chest you can see the little bumps. The center area was all those before it turned to peeling.

[2DogsFarm]

My TWH is highly reactive go bug bites.
In the past it’s been confined to hivelike bumps on his neck & jaw. This year, cannons, elbows & brisket are involved.
He gets 10 zyrtec twice a day & I’ve tried different anti-itch stuff - benadryl, hydrocortisone…
Latest is a 1.5% hydrocortisone cream & that seems to be giving him relief.
Sam’s Club sells a 4-pack of 2.5oz tubes under $8, a tube lasts me nearly a week.

[Marla_000]

Another thought- I read that permethrin ( a common ingredient in fly spray) would be in short supply this year due to high tarrifs- could the mfrs.of
Fly spray be using a new or different ingredient in lieu of permethrin?
I’ve used Endure for many, many years and have never had the scalding before, only when cheaper, oil bases spray was used.

[islgrl]

I’m thinking fly spray…

[Simkie]

I’d also pin this on fly spray. Mine will also pop with this stuff from time to time despite using the same brands, even though they usually don’t have any issues. I assume it’s a combo of weather (sun etc) and wetness (sweat etc) along with the potential of an extra large spray or the sprayer being just slightly out of whack and dispersing bigger droplets.

[outside_leg]

I had one that popped hives like this last year. We ran an allergy panel, and he had a bad ragweed allergy. We’ve treated with allergy serum for the last year, and haven’t had a bad reaction thus far this year.

When my vet first looked at them, she also mentioned she’d similar eruptions when people combine fly spray with Equiderma specifically. We didn’t use that product, so it wasn’t the case with him.

Allergy shots work well, but there is a long lead time. It would be the sort of thing that helps next year, maybe not this year.

[SonnysMom]

A number of the horses at the farm where I work get hives from the rain. Some of them then scurf. A few cases needed to be helped with a shot of Banamine since they were so bad.

[ThreeWishes]

Fly spray will do that. Especially oil based when they rub. And are in the sun and heat. Had it happen. It’s not an A=B. Thing. It’s more like. I’m being eaten alive by whatever environmental demon du jour so I scratch my chest and it’s hot and I’m sweaty. Voila. Hives plus edema plus peeling irritated skin.

[fjordmom]

Could it be photosensitivity to some of the fly spray ingredients? I had a dark bay TB years ago that was fine most of the time, but would get hives from bug bites (or so I thought). Then the hive area would turn to scurfy, peeling skin after a few days; much like a peeling sun burn.

At one point, I realized he had become sensative to Flicks and some other citronella based sprays. I stopped using those products and the problem seemed to largely go away too. In today’s business climate, formulations coudl be inconsistent and product QC could well be lacking.

I found puoring witchhazel on the itchy areas and rubbing it around with my hand helped a lot and also brought the hives down rather quickly. I just kept a botle of it in the barn fridge. He made it obvious that he liked that.

[ThreeWishes]

Indeed. Peeling skin can be very indicative of a sunburn/rash/sensitivity.

[kaya842]

Adding in another vote for fly spray. Had this happen to my horse when I tried using SmartPaks own fly spray several years. I stopped using the spray and it went away in a week or 2.

[IPEsq]

If it was my sensitive bay horse, the list would include fly spray, alcohol, liniment or soap residue, chlorhexadine or other antiseptic, gnats, rain, any kind of oil or ointment that has a chance of increasing photosensitivity, ….

I’ve found the Equiderma neem shampoo with some scrubbing helps once you are in scurf stage. But apparently not the conditioner because even following the directions (diluting it and rinsing), it seemed to make things worse. The Bio Skin Oil from Leovet rubbed in really well can help soothe and prevent additional flaking. But it carries a risk of photosensitivity so can only be used when fully covered with a fly sheet and then I shampoo off the next day.

[PaddockWood]

Your guy definitely got into something with that swelling. Huh.

My new guy is sensitive and will have a bout of hives and then also that surf/dried skin stuff on his chest which I know every time for us is the fly spray - a delicate skin area for sure.

I’ve had really good results now with two horses using Respire by Horsetech. I’ll dose 2 scoops/day for a couple days and the hives back completely down.

I find the scurf goes away if I just back off the fly spray a bit.

[PaddockWood]

And gotta come back and add that he is some kinda pretty coming out of his withers like that. Pretty boy!