Q: I know horses need it, but how do I know if my horse is getting enough, and the right kind, of Vitamin E?
Dr. Pat: Vitamin E is the #1 antioxidant that horses naturally consume to protect themselves from free radicals and oxidative stress. Horses do not make or synthesize Vitamin E themselves, so it can only be obtained through diet. Fresh pasture grasses have a significant concentration of vitamin E, but most horses in training and competition are predominantly in environments where they most likely are not receiving fresh pasture, and thus, need to supplement E into the diet.
Hay has very low concentrations of Vitamin E. Even though you may have the same species of fresh grass in pasture, once the pasture is cut and turned into hay, due to the natural storage process and drying, much of the vitamin E that would be in those fresh grasses is diminished considerably.
Feed manufacturers do incorporate Vitamin E into complete feeds, but the problem there is that the form of Vitamin E typically used in complete feeds is a synthetic source of Vitamin E.
You can go and check the source of Vitamin E in your feed by looking for these particular letters: synthetic Vitamin E it is going to have the letters dl-tocopheryl acetate.
Natural Vitamin E will be denoted as d-alpha-tocopheryl acetate. As you can see, they appear to be the same, but the "L" is the only difference. The "L" denotes the synthetic vitamin E which has reduced bioavailability in comparison with the natural form of Vitamin E. You almost exclusively see the synthetic form in equine feeds. With that lower bioavailability, you would have to administer an amount of feed that would be excessive in terms of the true nutritional requirements and energy requirements of the horse. It would be beneficial when your horse is showing and training, especially when it is not receiving fresh pasture access, to administer a natural source of Vitamin E to that horse.
So now that we have established the differences between natural and synthetic Vitamin E, let's focus on the natural forms.
There are two types of natural Vitamin E that can be administered to your horse. The first type, as mentioned, is d-alpha-tocopheryl acetate. That would be referred to as a protected form of Vitamin E, that makes it more stable. This type is what we include in our Equithrive Vitamin E pellets.
The second type of natural Vitamin E occurs in a liquid form, denoted as d-alpha- tocopherol. This type is commonly found in liquid products, in what is referred to as a nanoemulsion. To produce a nanoemulsion, you are taking a fat soluble vitamin, such as Vitamin E, and incorporating it into an aqueous (water-based) environment. Typically, that requires high energy through ultrasound (or ultrasonication) to produce extremely small fat droplets in water. The reason we decided not produce a nanoemulsion is because many of these nanoemulsions are particularly unstable. They are great for the first 30 days that you have the product, but after that you have a phenomenon called 'after-ripening'. This is where Vitamin E nanomolecules are combining with one another to where they form globules and fall out of solution. Therefore, the quality of those Vitamin E nanoemulsions deteriorates very quickly over time, particularly once you have opened the bottle and they are exposed to air, the after-ripening process starts to occur. If you are storing those nanoemulsions at low temperatures (like in the barn during winter), you would lose much of the efficacy.
That's why we opted to use natural Vitamin E in a pelleted form: increased bioavailability and stability that is highly palatable and easy to administer to ensure your horses are getting adequate E and omega 3 intake, no matter the season or environment.
Dr. Patrick Lawless, PhD, is the president and founder of Thrive Animal Health.