23/10/2026
๐๐๐๐ฝ๐ถ๐ฐ๐ฎ๐น ๐ ๐๐ผ๐ฝ๐ฎ๐๐ต๐ (๐ฆ๐๐ฐ๐ฎ๐บ๐ผ๐ฟ๐ฒ ๐ฃ๐ผ๐ถ๐๐ผ๐ป๐ถ๐ป๐ด)
Atypical Myopathy is a potentially fatal disease in horses.
Cases are most commonly seen during the autumn and spring months, particularly following wet, windy weather conditions.
As we are experiencing extremely windy conditions at present it is important that horse owners are aware of the signs.
Sycamore seeds and seedlings are the main cause of Atypical Myopathy.
Disease is caused through eating toxins found in the seeds (which have a helicopter like appearance) and seedlings/young shrubs. These toxins affect normal energy production within muscle cells.
As a result, horses develop severe and widespread muscle damage, particularly affecting muscles responsible for movement, breathing, and maintaining posture.
Clinical signs include:
โข Sudden weakness or reluctance to move
โข Muscle stiffness or trembling
โข Sweating/colic like symptoms
โข Depression and lethargy
โข Difficulty standing or recumbency
โข Dark red or brown urine (myoglobinuria)
โข Increased heart rate and respiratory effort
The disease can progress rapidly and should always be considered a veterinary emergency.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
Diagnosis is based on a combination of:
โข Clinical signs and grazing history
โข Identification of sycamore trees, seeds, or seedlings in or around the pasture
โข Blood tests showing markedly elevated muscle enzymes (such as CK and AST)
โข Urinalysis demonstrating myoglobinuria (bloody urine)
๐๐๐๐ฎ๐๐ข๐ง๐ ๐ญ๐ก๐ ๐ซ๐ข๐ฌ๐ค:
โข Identify sycamore trees in and around grazing areas
โข Fence off areas where seeds or seedlings accumulate
โข Provide adequate additional hay/haylage to reduce risk of foraging/ingestion.
โข Rake/remove seeds if found in field.
โข Regularly monitor/remove sycamore seedlings in spring and seeds in autumn
โข Ensure clean water sources are available.
Testing sycamore seeds/seedlings for hypoglycin A is available and can help to aid understanding of the risks but a negative result does not necessarily guarantee that your field is safe.
If you suspect Atypical Myopathy, contact your vet immediately.
Early recognition and aggressive supportive treatment offer the best chance of survival, although the condition remains associated with a high mortality rate.
๐๐ฅ๐๐๐ฌ๐ ๐๐จ๐ง๐ญ๐๐๐ญ ๐ญ๐ก๐ ๐ฉ๐ซ๐๐๐ญ๐ข๐๐ ๐จ๐ง ๐๐๐๐๐ ๐๐๐๐๐๐ ๐ข๐ ๐ฒ๐จ๐ฎ ๐ก๐๐ฏ๐ ๐๐ง๐ฒ ๐๐จ๐ง๐๐๐ซ๐ง๐ฌ ๐จ๐ซ ๐ฐ๐ข๐ฌ๐ก ๐ญ๐จ ๐๐ข๐ฌ๐๐ฎ๐ฌ๐ฌ ๐๐ฎ๐ซ๐ญ๐ก๐๐ซ.
