Your Horse’s Vitamin E Needs

Equine nutrition is a complex field to navigate! Every horse is an individual with their own calorie and nutrition needs. When it comes to vitamin E, there is enough research and understanding to ensure every horse can have balanced levels of this essential nutrient.  It’s also known that some types of vitamin E are better than others for horses!

What is vitamin E?

Vitamin E is more than one substance; it's a family of eight compounds named tocopherols and tocotrienols. For horses, alpha-tocopherol is the one to watch. Alpha-tocopherol the most bioavailable, as your horse's liver prefers it! It's also fat-soluble, meaning it's absorbed with fats in the diet and stored in fatty tissue and the liver. Horses store only three other vitamins - vitamins A, D, and K.  

Vitamin E is also an essential nutrient, meaning your horse cannot make it himself. Horses must receive their essential vitamins and minerals from their diets. When you think about wild and feral horses, their diets are grasses and naturally found plants. The domesticated horse, our companion, typically has a hay-based diet. Hay has many valuable benefits for horses, but those missing essential vitamins and minerals, such as vitamin E, need to come from other sources.    

Types of vitamin E 

Pasture grass is a natural source of alpha-tocopherol - the type that horses use! Of course, it's not always available. 

However, there are commercially available vitamin E sources for feeds and supplements. Some are better than others, that's for sure! In most situations, a commercially produced vitamin or mineral replacement is equally effective as the natural source - except in the case of vitamin E.  

Naturally sourced tocopherols will have a 36% higher rate of biological activity than synthetic tocopherol.

How do you tell the difference when you are shopping for supplements? Naturally sourced vitamin E will be labeled as d-alpha-tocopherol, while synthetic vitamin E will be labeled as dl-alpha-tocopherol.

There are three primary sources for Vitamin E supplements. Stand-alone vitamin E is available, as is vitamin E as part of inclusive vitamin and mineral supplements, and sometime it’s included in horse feeds and ration balancers.  

It's important to note that bagged feeds and grains for horses are required to show ingredients and a guaranteed analysis. You will see vitamin E as part of the ingredients! However, they are not required to disclose which type of vitamin E is used - the naturally derived or the artificially created version.  

It's also worth noting that many horses do not receive the proper feed amount for their body weight and nutritional needs based on the feed's recommendations. Feeds and supplements are only helpful when fed correctly!