Botulism in Horses: An Update

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Rising hay prices and the financial crunch caused by 2009’s Great Recession drove many horse owners to seek less expensive forage sources, including large round bales, haylage, and silage. But according to Amy Johnson, DVM, Dipl. ACVIM, compromising on hay quality and feeding from half-ton bales led to a larger problem: an uptick in reported cases of equine botulism.

Johnson, who studies the disease at the University of Pennsylvania’s National Botulism Reference Laboratory and treats horses at the university’s New Bolton Center, presented a lecture on “Advances in Diagnosis and Treatment of Botulism” at the American College of Veterinary Internal Medicine Forum, held June 12-16, 2013, in Seattle, Wash.

So, what advances have taken place in the diagnosis of botulism in horses?

“The short version: Not as many as we’d like,” Johnson said lightly, before giving an overview of the bacterium, its toxin, the neurologic disease it causes, and current recommendations for diagnosis and treatment

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Written by:

Michelle Anderson is the former digital managing editor at The Horse. A lifelong horse owner, Anderson competes in dressage and enjoys trail riding. She’s a Washington State University graduate and holds a bachelor’s degree in communications with a minor in business administration and extensive coursework in animal sciences. She has worked in equine publishing since 1998. She currently lives with her husband on a small horse property in Central Oregon.

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