Horse Breeds at

Poisonous Blister Beetles

Printer Friendly
Cantharidin, the highly toxic substance found in blister beetles, can cause severe complications and death if ingested by your horse. Blister beetles swarm in alfalfa fields and can accidentally end up in hay bales. The best way to avoid the deadly pests is to check your hay for their presence—dead or alive. Blister beetle poisoning is a red-alert emergency and requires immediate veterinary care. Signs that your horse may be suffering from blister beetle toxicity include:

• Blisters in the mouth and on the tongue
• Salivation (usually due to blisters)
• Goes off feed
• Increased heart and respiratory rates
• Sweating
• Fever
• Colic
• Diarrhea
• Endotoxic shock (indicated by discolored gums)
• Blood in manure or urine
• Thumps (referred to as synchronous diaphragmatic flutter; can look like hiccups)
Printer Friendly

 Give us your opinion on
Poisonous Blister Beetles

Submit a Comment   Join Club
Earn 1,000 points! What's this?
Reader Comments

Gaye    Wister, OK

3/22/2013 1:19:25 PM

I appreciate this information. But it would be very helpful to have even more. In which states are they most prevalent? What is the recommended veterinary course of treatment (in case our local vets don't know)?

Judy    Federalsburg, MD

6/24/2012 2:05:13 AM

I have noticed an increase over the past several years of various beetle type insects in my barn, concurrent with my use of alfalfa or alfalfa mixes for my horses with ulcers. So far no horse has exhibited signs and symptoms. How prevalent are blister beetles on MD's Eastern Shore, and what can I do to prevent importing them to my farm?

PKL    Somewhere, WY

3/26/2012 6:09:28 AM

Another issue for me to worry about.

Cassie    Lyons, NE

4/12/2011 3:48:09 PM

I wish there was more about how many different kinds there are and the differing poison levels in the different beetles.

View Current Comments

Top Products
Close X