Atypical Myopathy

With the recent wet and windy weather, please check your pastures for sycamore tree seeds and seedlings. The fallen seeds can contain a toxin called HGA which causes Atypical Myopathy (sycamore poisoning) in horses when ingested.

There are a number of things you can do to help prevent ingestion of sycamore seeds and therefore help to prevent Atypical Myopathy (AM):

  • Ideally moving your horse to pasture where sycamore seeds have not fallen, although often this is not possible. If possible, fence off any areas of the pasture where sycamore seeds have fallen.
  • Removing sycamore seeds/leaves from pastures.
  • Providing supplementary hay/haylage, especially when grazing is poor. However, avoid leaving wet hay on the ground as this can increase the risk.
  • Provide supplementary concentrate feeding.
  • Reduce time spent at pasture.

Not all horses on problem pastures are susceptible, but we cannot tell which are high risk.

Atypical myopathy signs include:

  • General weakness/sudden collapse.
  • Depression – holding head low.
  • Muscle tremors.
  • Signs of colic.
  • Brown or dark red urine.

Blood tests can confirm the diagnosis, which is sadly frequently fatal. Treatment can sometimes be successful depending on the severity of the condition and if started early enough.

If you suspect your horse is showing signs, please contact BELL EQUINE on  01622 813700 immediately.

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