Atypical myopathy, also referred to as seasonal pasture myopathy, is a disease that can quickly debilitate a horse and can prove to be fatal in more than 75% of cases.
Research studies identified the presence of the toxin hypoglycin-A in sycamore seeds as a cause of atypical myopathy. Sycamore seeds are of course most prevalent during the winter but cases of atypical myopathy can also occur during the spring.
Due to the spring outbreaks, it has been suspected that sycamore seedlings were the causal factor of atypical myopathy. This link has now been confirmed by the Université de Liège who have identified that sycamore seedlings also contain the toxin hypoglycin-A.
For horse owners, the challenge of removing sycamore seeds and seedlings can be a daunting and onerous task. One of the preventative measures is to ensure horses have sufficient grazing available to help deter their need to search for additional food. At this time of year, some horses will have to be kept on restricted grazing to help control their weight and prevent laminitis; therefore it is vital to regularly check such pasture for sycamore seedlings and the first sign of ragwort rosettes.
Further information is available from the advisory literature on atypical myopathy which can be downloaded here or contact the welfare team on 02476 840517 or firstname.lastname@example.org