With increased warnings about atypical myopathy, vets are warning owners to take extra care in identifying potentially dangerous trees — but not to panic and cut them down.

The seasonal disease — which is fatal in 70-80% of cases — has surged this year and is caused by a toxin in sycamore seeds.

Last week the RSPCA put out a further warning.

“It appears that vets have seen more cases of this debilitating and sadly often fatal condition this autumn than in previous years, and that risk is likely to be carried through to the spring,” said RSPCA chief inspector Cathy Hyde.

“We would urge horse owners not to graze horses near sycamore trees from the autumn through until late spring, and to check their horses at least twice a day.”

The British Equine Veterinary Association (BEVA) said the weather is to blame for the rise in deaths.

“The recent high winds and heavy rain have resulted in large numbers of seeds falling from trees in a very short period of time posing a risk to horses grazing on surrounding fields,” said a spokesman for BEVA.

“BEVA encourages horse owners to walk around their pasture to identify any sycamore trees within or adjacent to grazing land, so they can take steps to reduce the risk of this disease.”

Don’t rush to chop

Some readers have said they have cut down trees already.

But H&H vet Karen Coumbe said she is “very reluctant” to encourage people to do this — though it is vital to identify the trees correctly.

Trees are important on many levels, not least for shade in summer for horses,” said Karen.“If you have lost a horse, it must be very hard not to think of chopping trees, but I would plea not to rush now as the trees will be appreciated next summer.”

Lee Hackett from the British Horse Society added: “There is much to consider before any trees are chopped down, you must check they do not have a preservation order on them.

“It is also worth remembering that while chopping down the tree removes the immediate source of the risk, it does not remove the risk completely. Owners need to remain vigilant as the seeds can travel great distances by wind or water.”

Also beware acorns

Karen added readers should also be reminded that acorns can be poisonous to horses.

“Vets from Royal Veterinary College (RVC) and Bell Equine have just published a very relevant scientific paper in the Equine Veterinary Journal that reviews suspected acorn toxicity in nine horses. This showed that recovery is possible in mildly affected cases, but was sadly fatal in two thirds of the cases reviewed,” she said.

“Similar to the situation with sycamores, the disease is only seen in a small proportion of the population exposed to acorns and there seems to be an increased occurrence in certain years. Further investigation into factors predisposing to disease is required, but limiting exposure to acorns in the autumn seems prudent.”

Securing your land

Readers are also reminded trees might not be on their land.

Horse owner Andy Whelan contacted H&H due to seeds blowing onto his grazing.

“The fields in which our horses are kept are next to the M1 embankment. There are several sycamores and seeds fall into our fields,” he said.

“We endeavour to take precautions: removing any stray seeds from our pasture. However, it is becoming impossible to manage.”

They informed the Highways Agency, but were told “no action was needed”. H&H contacted the Highways Agency, which said it would look into it.

“It is worth reporting your concerns to the landowner, the Highways Agency in this case, however, they are under no obligation to remove the trees,” added the BHS.

This news report was originally published in H&H magazine on Thursday November 20, 2014

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