Veterinary advice to avoid acorn poisoning of horses

Acorns are poisonous to horses
Acorns are poisonous to horses
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WE have been inundated in the last few weeks with concerns from horse owners that their horses are eating acorns and how dangerous this is.

Thankfully this year we haven’t seen any cases yet, but it is important to find out how to protect your horse from acorn poisoning.

Acorn poisoning is very rare in horses. Most horses will not choose to eat acorns. However, in fields where grazing is poor or limited then horses may be tempted to eat them.

Poisoning can occur in spring when young green leaves are eaten, but mostly occurs due to ingestion of the acorns in late autumn.

Acorns contain tannic acid which can cause kidney and liver damage, as well as gut problems (the greener acorns are more poisonous).

Most horses that eat acorns will be unaffected, but if grazing is poor, and large amounts are ingested, then signs to look out for are: depression, loss of appetite, colic, constipation followed by diarrhoea (which may contain blood), blood in the urine (red urine), weakness and uncoordination. Also acorn husks will be spotted in droppings.

There is no specific antidote to acorn poisoning, so prevention is important as it can be fatal. Horse owners should fence off oak trees (including area where acorns fall); use a garden blower to blow acorns into a hedge away from horses or roll the area so acorns are crushed into the ground and are unable to be eaten; supplement with plenty of hay etc if grazing is scarce so the horses are less likely to look for alternative feed; or move horses to another field if this is available.

Once a horse develops a taste for acorns they appear to become addicted.

If your horse has been known to consume acorns, monitor it closely for signs of illness, and if concerned phone your vet.

Meanwhile, more than 30 ponies are reported to have been lost to acorn poisoning in the New Forest area so far this autumn compared to the usual six deaths a year.