Beau's bright, interested eyes and shiny coat do not give any indication that he was at death's door just a few months ago. On June 1, the chocolate-colored Rocky Mountain Horse gelding was a guest for the American College of Veterinary Internal Medicine's (ACVIM) annual edition of "Pet Survivor" during the group's annual Forum in Louisville, Ky. Two veterinary internists who nursed Beau back to health during his exhaustive 17-day hospital stay were on hand to discuss his case.

Andree Berthiaume, DVM, was visiting her family in Canada during the Christmas holiday and returned to her London, Ky., farm on Dec. 31, 2005. "I came home to a sick horse," she said. "There was mud in the water tub from where he had been trying to eat mud and drink water. He was ataxic (incoordinated), so I thought it was something neurologic."

Fairfield Bain, DVM, Dipl. ACVIM, ACVP, ACVECC, MBA, was on call at Hagyard Equine Medical Institute in Lexington, Ky., that weekend, and he consulted with Berthiaume by phone on what to do about the case. He recognized that the clinical signs Berthiaume described suggested botulism. Berthiaume had never encountered the disease in years of working with horses in Canada, so Beau was not vaccinated against it. The disease is more commonly seen in Kentucky.

Beau wasn't down or recumbent (unable to rise), but it was apparent his condition was deteriorating, so Berthiaume took him to Hagyard. "He fell in the trailer and couldn't get up," said Berthiaume.

Horses usually become infected with botulism by ingesting the neurotoxin produced by the anaerobic bacterium Clostridium botulinum in contaminated feed or water. Bain said that 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.

Kathy MacGillivray, VMD, Dipl. ACVIM, treated Beau upon his admission at Hagyard and was the main clinician to handle the case. She gave Beau a guarded prognosis and forged ahead with treatment, which included use of a botulism anti-toxin, intravenous (IV) fluids, IV nutrition, intra-nasal oxygen, antibiotics, analgesics, anti-inflammatory medications, and intensive nursing care.  

"For 12 days he didn't swallow," said MacGillivray. "He received intravenous feedings and nutrition through the nasogastric tube." She said while Beau was down, he had to be turned from one side to the other every few hours to minimize formation of pressure sores. "Once he was sternal (on his chest and belly), he was able to eat a soft mash."

Beau's time at Hagyard was not without complications: He had a vein that thrombosed (a clot blocked the vein in which he was receiving IV nutrition and medications), he developed liver dysfunction secondary to fat mobilization (also known as fatty liver disease), and he suffered from colitis, likely secondary to changes in his nutritional status and antimicrobial therapy.

By Jan. 16, MacGillivray and Berthiaume knew they needed to get Beau up, or he wouldn't survive because of breathing complications due to recumbency. "We don't normally put (these adult botulism cases) in a sling, but we did," said MacGillivray. "He was a fabulous candidate." Beau alternately spent several hours in the sling and several hours lying down in his stall.

Slowly, Beau returned to health, and by Jan. 17, he was discharged from Hagyard. He was treated on the farm for gastric ulcers, which were likely due to not being able to eat for several days and use of anti-inflammatory medications. Since then, his pressure wounds have nearly healed and he has been saddle trained.

Bain noted that Berthiaume's quick decision to refer the case was pivotal. "You want to catch these cases as early as possible in order to intervene with the antitoxin," said Bain. "The antitoxin prevents further binding of the toxin to the nerve endings (neuromuscular junction). The outcome is often determined by the amount that is already bound by the time we get to see them in the hospital. The situation usually is that there is still toxin present in the intestine that will continue to be absorbed over time. We also use laxatives and absorptive agents orally in an effort to prevent further absorption of toxin across the intestinal wall."

Beau doesn't show any long-term effects of botulism other than his healing pressure sores and ridges across his hooves that show an aberration in hoof growth at the time he was sick (the new growth above the ridges looks normal).

ACVIM's "Pet Survivor" spotlights cases that were successfully managed by veterinary internal medicine specialists to help build awareness of the specialty. There are 392 large animal veterinary internists practicing in the United States (a portion of these are equine-specific internists, but ACVIM doesn't currently have a breakdown into species). These individuals are readily available for referral from general equine practitioners. Horse owners can search for nearby specialists at the ACVIM's web site:

About the Author

Stephanie L. Church, Editor-in-Chief

Stephanie L. Church, Editor-in-Chief, received a B.A. in Journalism and Equestrian Studies from Averett College in Danville, Virginia. A Pony Club and 4-H graduate, her background is in eventing, and she is schooling her recently retired Thoroughbred racehorse, Happy, toward a career in that discipline. She also enjoys traveling, photography, cycling, and cooking in her free time.

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