The Way Of Horses
Live Oak

By Eleanor Richards
© Copyright 2008

Does your horse eat like a pig?

Yes! Then acorns are one porcine delicacy he should avoid.

Acorns are seeds or nuts produced by oak trees. There are more than 60 varieties of oaks in the continental United States. The bark, leaves and acorns contain an acidic chemical commonly known as tannin.

Tannin has a bitter taste and is an astringent (contracts tissues and draws out fluids). It can damage the liver and kidneys of horses. Tannin also interferes with the utilization of protein.

All plants contain some level of tannin. Oaks contain high levels. Within the family of oaks, red or black oak varieties contain the most tannin; white oak varieties contain the least. Buds and early spring leaves have a higher concentration of tannin than mature leaves. Green acorns have a higher concentration than ripe acorns.

Squirrels, birds and deer eat acorns with no apparent problems. These free roaming species search out the less bitter tasting acorn varieties (less bitter means a lower tannin level). Stored and ripe acorns that have been soaked due to rain will also be lower in tannin. Tannin is water soluble and leaches out. It is important to note these animals have access to other foods which will help buffer and dilute the tannin.

Poisoning due to the ingestion of acorns is rare in horses which have access to plenty of good quality forage. An occasional acorn throughout the day should not harm a healthy horse with a digestive system full of long-stem fiber.

The ingestion of buds and spring leaves should be avoided. Make sure low hanging or broken branches are removed before they can be eaten. Providing plenty of forage will help deter horses from eating these forbidden windfalls.

Occasionally a horse will develop a taste for acorns. Such an individual would rather eat acorns than good quality forage. If your horse is one of these fanatics you will have to remove the horse from the pasture which contains the forbidden nut.

The signs of acorn poisoning can be: loss of appetite, excessive salivation, blood in the urine or manure, colic-like pain, slow or irregular heart-rate, elevated temperature, pale mucous membranes, watery eyes and a depressed attitude. In the early stages manure is hard and dark in color; the horse may be constipated. Often, in the later stage, the manure changes to diarrhea. Mouth ulcers may form; salvia may escape from the nose. In extreme cases liver and kidney failure ensues and other organs begin to hemorrhage. Some poisoned horses may founder.

Horses that are extremely sensitive to tannin or have eaten large quantities of oak leaves, bark or acorns may die.

If your horse develops acorn poisoning there is no antidote. The common treatment is supportive care. The affected horse must be removed from the source of the poisoning. Your veterinarian will probably give intravenous fluids to help flush out the toxins. Mineral oil and charcoal may be given to help rid the digestive system of the tannin. Hay and water is made available, which also helps dilute the poisonous material in the digestive system. Your veterinarian may also give pain killers to help make your horse more comfortable.

The best thing for the health of your horses and trees is to protect them from each other. Horses are hard on trees. They disturb the root system, chew the bark when bored and rub the branches. Forests or woods do not make good pasture. Fence off any trees. If the trees are providing shelter or shade erect a horse-safe structure, such as a three-sided loafing shed.

There is nothing more beautiful than a majestic oak tree and a horse they just shouldn't be in the same picture.

* Test your equine nutrition knowledge at www.thewayofhorses.com/nutrition_quiz.html

* You can get a Bachelor of Science degree in equine studies or certification as a Professional Horse Trainer or Riding Instructor online. Visit www.horsecoursesonline.com for information.

Eleanor Richards was raised training and caring for horses. She learned to ride and care for the horses her family bought and sold. Many of these horses required improved nutrition when they arrived for training. Eleanor's experience and research has benefited both horses and horse lovers in the field of equine nutrition.

The equine nutrition consultant for Western Reserve Farm Cooperative, located in northeast Ohio, she keeps busy doing equine nutrition consultations, conducting seminars, and speaking to youth groups about horse care and nutrition. Eleanor is the author of the syndicated column The Way of Horses. She has more than 20 years experience helping and being a mentor to those wanting to know how to provide the very best care and nutrition for our special friend - the horse. Richards is also the author and instructor of the online course "Nutrition for Maximum Performance". This course is offered by Breyer State University as part of the Bachelor of Science in Equine Studies program, New Mexico State University, Paradise Valley Community College, Allegany College of Maryland, Scottsdale Community College, Iyuptala University, and Success is Easy's certified Professional Horse Trainer program. Visit Eleanor's web site at www.thewayofhorses.com or contact her at (440) 554-3714