Supplementing Vitamin E for Horses

You can supplement your horse if needed

What is vitamin E for horses?

• Vitamin E is a potent and important antioxidant that helps protect cells from damage caused by free radicals. These free radicals are created via oxidative stress within cells as the body uses fats and carbs. Free radicals have an odd number of electrons; hence, they are unstable. Fixing this instability requires free radicals to steal electrons, contributing to cell damage and death. Vit E fights this process.  

• Exercise and aging take a toll on the body. There’s an increase in energy use, creating a more significant need for antioxidants. When free radicals outnumber antioxidants, your horse may have sore muscles, stiff joints, and tissue damage.

• While there are many antioxidants, such as carotenoids, amino acids, and vit C, vitamin E is unusual. There is no specific body function that needs this essential nutrient. Vit E is known to help with many body systems: the muscular, circulatory, nervous, reproductive, and immune systems. 

• Vitamin E deficiency opens the door to health problems, including muscle weakness, poor immunity, and even neurological problems.

Pasture grass is the best source of natural vitamin E for horses.

Your horse’s neuromuscular system and nutrition

• General poor performance and muscle soreness can be related to vitamin E deficiency. Additionally, three neurological disorders link directly to vit E deficiency.

Equine neuroaxonal dystrophy (eNAD)

• Equine neuroaxonal dystrophy affects foals and young horses and has a genetic component. With long-term vitamin E deficiency, a horse may become uncoordinated, clumsy, and even suffer extreme debilitation. One working theory is that vitamin E protects the brain and spinal cord neurons while a horse grows. 

Equine degenerative myeloencephalopathy (EDM)

• (EDM) is a more advanced form of eNAD and affects the horse’s central nervous system. Abnormalities in the spinal cord and brainstem affect the gaits, usually appearing in foals under one year old. You may see them act uncoordinated, have a weird gait, drag their toes, and find it difficult to back up.

• Later in life, EDM can develop, and horses usually show behavioral changes, are more anxious, and tend to isolate. EDM usually has a genetic basis, and some breeds like the Lusitano, Appy, Standardbred, Pasos, and Arabs are often affected.

Your horse likely needs some supplements for maximum health.

Equine motor neuron disease (EMND)

• Older horses deficient for extended periods, usually 18 months or more, experience nerve malfunctions if they have EMND.

• A horse with EMND may lie down more than usual, hang their head low, and have an awkward stance. Horses also sweat, show muscle loss, weaken, and lose weight.

• There is a possibility for recovery, and unlike EMD, it does not have a genetic component.

Vitamin E deficient myopathy

• Horses with short-term deficiencies may show twitching and muscle weakness. There are no obvious and direct neurological changes; adding this essential nutrient to the diet usually leads to recovery.

• In other cases, horses with neurological disorders like equine protozoal myeloencephalitis (EPM) and Wobbler’s syndrome may benefit from additional vitamins, including E, in their diets. It’s worth having your horse’s bloodwork checked for serum levels of vitamin E, and many vets encourage a high dose when being treated for EPM to give the horse higher levels of vitamin E.

Any sign of neurological disorder warrants a complete exam from your vet.

Vitamin E and Selenium – Is There a Deficiency?

• Selenium is a mineral that plays a vital role in the horse’s body, regulating thyroid hormone activation and acting as an antioxidant. A selenium deficiency may lead to muscle degeneration and cause some types of tying up in horses. 

• Selenium is found in soils and will affect the selenium in a horse’s forage supply. Where your horse’s hay is grown will impact how much selenium they receive, and your horse may need selenium and vit E supplementation. 

• Here’s the deal with selenium – it works alongside vitamin E. The two antioxidants may compensate for each other if there is a shortage. Selenium is also a nutrient you don’t want to overfeed – too much of a good thing can cause problems. This is another great reason to work with an equine nutritionist – to avoid excess.

• Many supplements also offer magnesium with selenium and vit E, which may or may not be necessary for your horse.

• You may also find vitamin E in omega-3 fatty acid supplements, which is impressive, as those fatty acids help squash a horse’s inflammatory response.

Selenium deficiency and disease

• White muscle disease, formally known as nutritional myodegeneration (NMD), happens when young foals don’t have enough selenium in their milk supply. This causes muscle breakdown, often affecting cardiac muscle. NME can also make swallowing difficult and increase the risk of pneumonia.

• It’s also related to a vit E deficiency.

Providing vitamin E via supplementation

• As horses produce only small amounts of vitamin E, the diet must provide it. For this reason, horse owners must give their horses with a balanced diet that includes sufficient levels of vit E. 

• Your horse’s needs may vary depending on the season and the availability of fresh pasture. And while it’s readily available to horses as pasture, vitamin E disappears a week after being cut for hay. 

Tocopherol types

• It’s worth noting that some forms of vitamin E are more beneficial to horses than others. The natural form of vit E, d-alpha-tocopherol, is more easily absorbed and utilized by horses than synthetic vitamin E, dl-alpha-tocopherol. Therefore, horse owners should strive to provide their horses with natural E whenever possible. 

• Research tells us that tocopherols in the wilds of nature are 36% more biologically active than the synthetic form. 

• Look for d-alpha-tocopherol in the active ingredients of any supplements you add to your horse’s diet.

Read the labels and look for d-alpha-tocopherol – the natural variation

• You can find vitamin E in a few sources – a stand-alone supplement, as part of a bagged feed or ration balancer, or out in nature’s salad – the pasture. For supplements and feeds, you may not know which version of vitamin E you are feeding. Some brands, however, will specify which version is included.

• Feeding supplements is easy by top-dressing or mixing with bagged feeds or adding to hay piles. You can split dosages into several offerings in a day.

Daily Requirements of Vitamin E for Horses

• The smart folks at the National Research Council (NRC) have insights on appropriate dosages for your horse’s wellness. 

• The baseline Vitamin E dosage for horses is 1-2 IU per kg of body weight. So, a 500 kg (1,100 lb) horse needs 5000-1000 IU of vitamin E daily.

• If your horse is a performance horse, pregnant, or lactating, consider the daily dosage to be about 1,000 IU. Young horses should receive about 500-75- IU vit E daily.

• Underweight horses have less fat to store vitamin E for a rainy day, so they may need more, too.

• Research studies show an upper safe diet concentration of 10,000 IU, but this should be done with the help of a vet and equine nutritionist.

Larger doses

• Could larger doses be more effective? Yes, tighter levels of vit E are helpful, especially if your horse has:

• Metabolic disorders like equine metabolic syndrome (EMS), PPID (formerly Cushing’s), and insulin resistance (IR).
• Allergies
• A muscle disease or compromised muscle function
• Neurological problems
• An injury or disease

Pasture and hay as sources

• It’s easy for horses to meet their daily requirement when they graze all day. Fresh green grass provides upwards of 2,000 IU per day. Of course, this varies seasonally, and reserves stored in fat tissue may not last through the winter.

• For hay, vitamin E levels drop over time. This happens as hay ages and levels begin to decline after a week. It’s common for one month of hay storage to see vitamin E levels drop by half. For horses without pasture, you’ll need a dietary supplement.

A quick reminder that equine nutritionists earn PhDs about diet and horse health, and are affordable!