Beware of Oak Poisoning!

"It can be very difficult to diagnose chronic poisoning in horses caused by the consumption of acorns, says Dr Mac."

- By Dr Mac

A majestic row of ancient oak trees alongside rolling green pastures is often a feature of expensive equestrian estates in England, the US and parts of the Western Cape. Only a few horses develop a taste for the acorns, leaves and bark of these trees, and the signs of chronic poisoning are not always obvious, although they can be life-threatening.

Oak poisoning often occurs when a horse is moved for the first time into a paddock where there are oak trees, when there is overgrazing, or when drought decreases the quantity and palatability of the grass. Not all horses will eat acorns, but it is possible for some of them to become addicted to acorns.

Green acorns and young leaves are more toxic than the more mature ones, so signs of poisoning may occur seasonally in spring, particularly after heavy rain. Fatal acorn poisoning in free-ranging pigs has been recognised for centuries, and has also been described in cattle and dogs.

SIGNS AND SYMPTOMS