Bare pastures and potential hay shortages, coupled with winds blowing seeds from laden sycamore trees, have created a perfect storm to increase the risk of atypical myopathy in grazing horses, BEVA warns. | Photo: iStock

Bare pastures and potential hay shortages, coupled with transatlantic storms blowing seeds from laden sycamore trees, have created the “perfect storm” to increase the risks of atypical myopathy for grazing horses, warns the British Equine Veterinary Association (BEVA).

Experts are advising owners to take steps now to minimize the risk of horses developing this often-fatal disease.

Atypical myopathy, a sudden-onset muscle disease, has been recognized in horses for over 60 years but its cause, the toxin hypoglycin A, was not identified until 2013. In the U.K., the most common source of the toxin is the Sycamore tree (Acer pseudoplatanus), a member of the maple tree family. In North America the Box Elder (Acer negundo) is the most common tree to cause the disease (referred to in the U.S. as seasonal pasture myopathy)