This article is about a vitamin (E) and a mineral (Selenium). In equine medicine the two things are usually talked about together because in combination they can really help performance horses. ESe (pronounced e see) is often far more effective for horses than joint supplements that cost 10x more.
First a disclaimer. I am writing about the needs of horses in New England. This information may not be useful or can be totally wrong in other areas of the country. For example, supplementing a horse with Selenium in the southwest may be dangerous. The soil there contains huge amounts of Selenium which is taken up by plants. One plant, locoweed, not only picks it up but picks it up in quantities that make it toxic to horses. Giving more Selenium in that area is not a good idea.
The dirt in Maine is Selenium deficient, and as a result, plants that grow here can’t pick it up. Selenium is important for healthy muscle function in horses. It is a small but critical part of some enzymes that clean up harmful free radicals in the horse. We think that Selenium also plays a part in the prevention of tying up, and veterinarians often recommend its use in horses with that issue. Although most grains list both E and Selenium on their labels the amounts are miniscule and of no real benefit.
Vitamin E is found naturally in green leafy plants. We do have E in our soil and plants but when hay is stored its levels drop. E is an antioxidant which is important in the maintenance of healthy nerves. Lack of it can cause some serious neurologic problems in horses. One is a disease known as EMND (Equine Motor Neuron Disease). Horses with EMND become uncoordinated and lose muscle tone. Over months the muscles shrink, and horses get very skinny regardless of how much they eat. It is closely related to “Lou Gehrig’s disease” in people.
Another disease in which lack of E seems to play a part is EDM (Equine Degenerative Myelopathy). With EDM the nerves of the spinal cord degenerate causing the horse to be ataxic. Like Selenium, low Vitamin E plays a part in horses that tie up, and usually large amounts of E are used in treating that problem.
In my opinion every working horse should be on this supplement. I usually recommend 2000 IU (International Units) of E and 2 mg (milligrams) of Selenium per day as a minimum for a 1000 lb horse. Some supplements have the two in that ratio, which makes feeding it very simple. If blood tests show that a horse is very low in E,
I recommend one of the regular ESe supplements and then add more pure E to get the blood levels up to normal.
ESe supplementation is also important for brood mares throughout their pregnancy. Foals born with a deficiency because of low levels in their dams may never get to their feet the first time.
I can’t tell you how many times I’ve watched a horse work that isn’t really lame, but is just not moving well. Before injecting this or that set of joints I ask if the horse is on E and Se. If not I will recommend it, and ask the owner to call in 2 weeks. Often within a week I hear back that the supplement has smoothed things out.
Vitamin preparations can be expensive and are sometimes worthless. ESe is one that is very cheap and often effective.
-David A. Jefferson, DVM