May 2007
Horses, Horses, Horses!

Horses, Horses, Horses!

This May is beautiful! It is one of the greenest Springs that I can remember. Horses in Alabama will be happy to eat the plenteous, lush, green forage of Springtime, and we as owners are glad to know that they have plenty of good, green grass to eat.

Yet something happened in the last few months of winter that is of tremendous concern for any horse owner who feeds alfalfa hay. This article is being written in direct response to a request from a concerned horse owner who was very upset at reports of local horses dying due to blister beetles that were infested in alfalfa hay.

If you feed alfalfa hay at all, any time of the year, then you need to be educated on the seriousness of blister beetles. The beetles have a toxin in their bodies that cause painful blisters to erupt inside the animal, causing diarrhea, colic, shock and often death.

This is such a serious matter that the Alabama Commissioner of Agriculture and Industries, Ron Sparks, put out a press release to warn Alabama horse owners about the potential infestation. In this release, the State Veterinarian, Dr. Tony Frasier, explains about what signs to look for and what to do. I am listing the press release here because I believe it is the best thing that I can do to help educate horse owners about these awful pests. 

Sparks Warns of Blister Beetle Poisoning in Horses

Commissioner Ron Sparks is warning horse owners about the potential infestation of blister beetles in alfalfa hay, which can fatally poison horses that ingest them. "Many horse owners have been purchasing alfalfa hay this year due to the shortage of grass hay caused by the drought last summer," said Sparks. "Blister beetles are attracted to and thrive in alfalfa hay. This is bad for horses because blister beetles have a toxin in their body, which causes painful blisters when it comes in contact with skin or mucous membranes." When accidentally baled in alfalfa hay, very small amounts of the dead beetles can kill horses or other animals that ingest the bugs.

State Veterinarian Dr. Tony Frazier said some signs of blister beetle poisoning in horses are salivation, colic, diarrhea, frequent urination, shock and death. There is no antidote to the toxin, cantharidin, but horses can be treated and given supportive therapy to help relieve the symptoms. If you suspect your horse may have been poisoned, you should immediately seek professional veterinary care to treat the horse. If cantharidin poisoning has been diagnosed in one horse, all horses in the barn that are eating alfalfa should be examined by a veterinarian. An individual horse’s sensitivity to the toxin and the amount of toxin consumed can cause variations in the time of onset and severity of the signs of poisoning.

Horse owners who must rely on alfalfa as feed due to the lack of grass hay can help protect their animals from blister beetle poisoning by being an informed consumer. The easiest way to check is to take a look at the hay. If the bale is infested you will be able to see the beetles easily.

Horse owners can also take additional precautions by finding out when the alfalfa was harvested. Blister beetles mature in July and August, so the first cutting is the safest in terms of reduced numbers of beetles. Later cuttings should be baled pre-bloom to reduce beetle numbers. Next, ask how the hay was harvested. Blister beetles often swarm alfalfa fields or sections of fields and then move on in a few days. Conscientious hay producers investigate alfalfa fields for the presence of blister beetles prior to harvest and delay harvest if beetles are present.

For more information about blister beetles, call the State Veterinarian’s office at 334-240-7253.

As Dr. Frasier has informed us, it is better to be safe than sorry. To review:

1) Check the hay you are purchasing before you pay for it. Make sure there are no beetles in the hay at all. Even one beetle ingested can harm a horse.

2) Know the seller of the hay and where the hay came from, so that it can be traced back if an infestation is discovered in the hay.

3) Of course, if you do believe that your horse has ingested blister beetles, call your veterinarian immediately. It very well may be a matter of life or death.

4) Once again, as stated previously, please call the State Veterinarian’s office for more information about blister beetles.

Once again I would really like to know what horse people want and need to know about their animals. Please feel free to send suggestions, questions, and comments to the mailing address: Cooperative Farming News; P. O. Box 2227; Decatur, AL; 35609-2227 or fax 256-560-2605, or email This email address is being protected from spambots. You need JavaScript enabled to view it..

Janet Bryant is a freelance writer from Oneonta.