Springtime Diseases

Atypical Myopathy – All Year Awarness

Atypical Myopathy is probably a phrase you’ve heard on more than one occasion over the last couple of years. It is a potentially – and often – fatal disease caused by the consumption of sycamore seeds. If you aren’t sure what sycamore seeds look like, think back to your childhood. You probably played with them! They are shaped like a boomerang, or helicopter blades, when you throw them up in the air they twirl around and around until they reach the floor. It’s hard to imagine such a tiny, innocent seed being so dangerous. It is crucial to be aware of diseases like this that progress so quickly all year round, as springtime (now!) is the other main time of year that cases of this Atypical Myopathy pop up. The problem is, that in this case the majority of people will be overly careful in the autumn (rightly so) and then forget about the springtime dangers as most of the information available will glance over springtime warnings and focus mainly on Autumn.

Atypical Myopathy cases are more often seen in the Autumn months when the seeds and leaves fall from the trees, however it CAN strike at more than one time of year.

  1. Sycamore Seeds, seen more often in Autumn

What can you do?

At this time of year, during the spring, the sycamore seeds that have been left over the winter will be starting to sprout into new plants. These tiny saplings (even when they first erupt from the ground) could potentially hold the toxin that causes Atypical Myopathy, though this is unproven other than in statistics that show the links between Atypical Myopathy cases and the time of year they happen. Ideally, any Sycamore trees around your horses pasture should be removed but realistically, this isn’t always a viable option. Unless you own the land & trees it is unlikely you will be able to remove them. Instead, you can ensure that any seeds blown or fallen into your fields are removed. There is no easy way to do this, often it’ll involve hand picking them from the field to ensure none are left behind.

Seedling 7

  1. Sycamore plants sprouting, seen in Spring

You may think, surely missing just two or three won’t make that big of a difference. Scientists have found through their research that different seeds have different levels of toxicity. This means that ¾ of the seeds fallen off your sycamore tree may not have dangerous levels, but the last quarter may have levels high enough to kill a horse quickly. There is no way to know which seeds have fatal levels of toxin within them, so the handful left behind could quite easily contain the lethal amount.

Atypical Myopathy often gets confused with Grass Sickness as the symptoms are very similar. The difference is that with Grass Sickness, the horse will suffer from muscle wastage.


What should I look for?
Part of being aware of Atypical Myopathy is knowing and understanding the symptoms. A lot of information will tell you the causes of such a disease, but often doesn’t cover much on symptoms. It is important to know symptoms on the off-chance you suspect your own or someone else’s horse of this disease as with Atypical Myopathy time is crucial to survival. Once symptoms are present, which can happen suddenly, the disease has already taken hold and is serious. This means you MUST call your vet or take your horse in for emergency care if it is safe to travel.

Signs and Symptoms are:

  • Muscle soreness / Stiffness
  • Muscle Tremors
  • Weakness & Lethargy
  • Fast / Laboured breathing
  • Red or Brown Urine
  • Choke
  • Fast and/or irregular heartbeat

Unfortunately, in some cases sudden death can occur.
These symptoms are also symptoms of other (most!) illnesses, so it is important to ring your vet even if you just see one or two symptoms, as though it may not turn out to be this disease, it could be something else.

It is important to raise awareness of such a disease, as there is still so much we don’t know about it. Despite the many articles going around informing the public, there are still many people who aren’t aware of the devastating effects something as small as a sycamore seed can have on their Equine friends.
For more information, visit the BHS Website where you can find leaflets and a poster on Atypical Myopathy.



  1. http://liphookequinehospital.co.uk/news/2014/11/atypical-myopathy-sycamore-poisoning-in-horses-information-for-owners/
  2. http://www.bhs.org.uk/welfare-and-care/recent-research/07-march-atypical-myopathy

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s