03/11/2026
🍂 Sycamore Toxicity - Do you need to worry? A previously very rare condition we are sadly seeing more cases.
Horses grazing in pastures with sycamore trees are at increased risk of Sycamore Toxicity (atypical myopathy) The dry summer and recent windy weather has contributed to an abundance of seeds (also known as 'spinning jennies' ) falling onto grazing areas.
Horses won't choose to eat the seeds so in paddocks with plenty of grass the risks should be low, however for those with reduced grass growth or restricted grazing offering supplementary forage in the fields may be required to reduce the risk.
If you are worried about the immediate risks to your horses you can send samples of the seeds or leaves to the RVC (Royal Veterinary Collage ) to test the levels of toxin (hypoglycin A ) in the individual trees .
https://www.rvc.ac.uk/equine-vet/news/equine-atypical-myopathy-toxin-and-biochemical-tests-and-tree-sample-testing-available-at-the-royal-veterinary-college
Signs of toxicity vary from lethargy, stiffness, loss of balance and low head carriage, to increased lying down, inability to get up, sweating and colic signs, as well as passing brown urine.
It is essential to seek immediate veterinary attention if you observe any of these signs in your horse - ☎ Please contact us to speak to one of our vets if you have concerns about your horse's health.