Botulism Is Cause of Death For A Dozen Horses In Wyoming

The deaths in April of a dozen horses on one pasture in Natrona County, WY were due to botulism. Over last weekend, KCWY-13, Wyoming's NBC affiliate reported that:

Dr. George Marble says 3 horses were already dead on April 10th and when he went to the ranch he found two more that weren't able to walk. Within two days, all twelve the of the rancher's horses were dead or euthanized. Almost all the horses suffered paralysis of the legs and tongue which are both classic signs of botulism. The vet says no other pastures were affected by the toxin.

The veterinarian told KCWY-13, "the animals that were upstream so to speak from this particular pasture cause there was a little creek that ran through and those downstream from those horses and those that bordered on a fence line are all unaffected."

An equine health site associated with Horse Magazine says: "Horses usually become infected with botulism by ingesting the neurotoxin produced by the anaerobic bacterium Clostridium botulinum in contaminated feed or water. Feed contamination can occur when the decomposing carcass of a rodent or bird is baled in hay. This is seen more often in round bales. Feed can also be contaminated through improper storage or poor fermentation. Rarely, horses can get botulism when C. botulinum from the soil gets into an open wound."

KCWY-13 said it is extremely important for ranchers to check the hay before feeding, especially in the summer.

New, Faster Tests Being Developed For Detecting Deadly Botulism Toxin

 The rare, but deadly botulinum toxin is millions of times more poisonous than cyanide.  As dangerous as it is, the test for detecting botulinum toxin--an assay requiring the participation of laboratory mice, is neither quick nor easy. It takes from four to eight days, is not portable, nor very affordable.

A new, improved test for detecting what's known as "serotype A" of the toxin has now been developed by Agricultural Research Service (ARS) biologist Larry H. Stanker and colleagues at the ARS Western Regional Research Center in Albany, Calif.

The new test relies on laboratory built molecules known as monoclonal antibodies, which can bind to the toxin. Assisting the work are biologist Luisa W. Cheng and research associate Miles C. Scotcher.

The botulinum toxin that causes botulism occurs in seven different serotypes--A through G. A and B are culprits in most of the foodborne botulism cases in this country, according to Stanker.  The research team now expects to complete assays for detecting serotypes B and E sometime this year.

Safeguard Biosystems, Inc., of San Diego, CA., is packaging two of the serotype A antibodies into a dipstick-style test kit that looks and operates much like a home pregnancy test. The botulinum kit is intended for testing liquids, such as beverages, or clinical specimens, such as blood or urine.

That should be much quicker than waiting around for those lab mice.

ARS, a unit of the United States Department of Agriculture (USDA), has much more about this in its May/June magazine here.