Possible blister beetle reaction?

[BlueDrifter]

Two weeks ago, Drifter was fine for grooming and tacking up – but near the end of a trainer ride, he began snorting so hard he was pulling the reins out of her hands. I didn’t see anything, but he was sweatier than usual, so we ended early and she walked him around to cool him out.

She returned 10 min later and he was breaking out in hives. His mouth was swollen bumps. I took him back to his stall, untacked, hosed off, put benedryl in his food. He refused to eat and collapsed.

I made up more benedryl and syringed it in his mouth while he was down. He started fleming like he was colicky. Called the vet, and they said they were on their way. My trainer looked at his gums and said he was shocky.

We got Drifter up after 20 min of being down, and he stayed up. But he kept going to his water, hanging his head over and dunking his swollen mouth, but not drinking, and still refusing food.

He started to drink two hours later, right before vet finally arrived. He ran a fever, and vet gave two dyprone shots, plus dex. We rinsed him off several more times. The hives started to decrease after the Dex, but were still visible four hours later. By nightfall, all okay. Vet thought it a severe reaction to a bee sting, which we assume he must have snorted in while he was being ridden.

Last week he was fine, in full training. Today… he started the snorting thing and would not canter, seemed labored in breathing. We stopped the lesson. He did not get hives and seems “normal” other than no energy to work.

I am having vet come this evening for a general blood panel, but I looked up “blister beetle” and he had every symptom. This load of alfalfa has been fed to 50+ horses and no reactions. He gets one flake in am and his symptoms happened about 3 hours post breakfast.

I am in SoCal, Moorpark area. In my 40 years I have never heard of a blister beetle reaction or fatality; but at a loss as to what might have caused this reaction.

I don’t think you can test for it, and I don’t think one can completely screen alfalfa for it.

Does this sound like a blister beetle reaction? Has anyone been able to screen alfalfa for it?

[lenapesadie]

I am not sure of the answers but jingles for your horse and hope the vet can help!

[StormyDay]

Well that is terrifying.
Have any horses in the barn had irritation at the mouth? Blister beetles have that name for a reason.

[BlueDrifter]

My vet has also worked on the East Coast, where blister beetle cases are more prevalent. She says they usually don’t present with hives…and there is more gastric and renal symptoms.

She was not the vet at his collapsing incident, but she is my main vet and said it was definitely a anaphylactic shock response to *something." She couldn’t rule out blister beetle, but says it is highly unlikely.

She has had a few horses with an allergic reaction whose faces blew up in five minutes while the owner watched, but none as severe as Drifter’s, and in those cases they never found out the culprit. For them, it never happened again. My finger’s crossed that Drifter has the same luck!

So now I am the proud owner of my own bottle of Dex IM. Muscle injection works in 10 min. Dex powder works in 30-40 min. Give it like an adequan shot.

She also said that Zyrtec or it’s generic works better than Benedryl, and I can give that anytime I am not sure what is happening, that it won’t hurt him if not needed, and won’t interfere with Dex if that is needed.

Glad to have blister beetle idea excluded. At least my worry goes back to bees/wasps for the moment!

[BlueDrifter]

No other horses experiencing it – but I read that blister beetles could be in one flake and not another and they are difficult to see. And even dead blister beetle body parts could cause a reaction. So, it would be possible for a single horse to react.

But the hives thing. My boy definitely had hives, and that does not seem to be a blister beetle reaction.

[JB]

@BlueDrifter

My vet has also worked on the East Coast, where blister beetle cases are more prevalent.

That seems odd, since the beetles really like alfalfa, and alfalfa isn’t grown (much) in the East. It’s a big crop in the Western areas.

I don’t see hives listed as a symptom here, but that doesn’t rule out a BB, as it could be an individual reaction to the sudden stress of whatehver.

Blister beetles in alfalfa hay | UMN Extension

[StormyDay]

@JB

@BlueDrifter

My vet has also worked on the East Coast, where blister beetle cases are more prevalent.

That seems odd, since the beetles really like alfalfa, and alfalfa isn’t grown (much) in the East. It’s a big crop in the Western areas.

I don’t see hives listed as a symptom here, but that doesn’t rule out a BB, as it could be an individual reaction to the sudden stress of whatehver.

Blister beetles in alfalfa hay | UMN Extension

Growing up we fed alfalfa and we never had to worry about the blister beetle because they weren’t in the area the hay was grown. However, with temperatures rising I wouldn’t be surprised if farmers that have never seen one before start having to deal with them.

[theresak]

Ask the vet about using that IM Dex orally or sublingually and which would be faster and/or safer if the horse is in the midst of an allergic reaction. I’m pretty sure I’ve pulled up IM or IV dex out of a vial and squirted it into the mouth for my horse.

[BlueDrifter]

@jb, I know, I thought it odd, too, but if you look at a map of blister beetle infestations, they are primarily east coast and southwest.

I assumed the east coast bought their alfalfa from the west…

My vet said she couldn’t positively exclude it, but thought it highly unlikely.

[BlueDrifter]

Oh, what an interesting idea, I will text her right now… thx