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3 Nutrients for Horses That Are Extra Important in Winter

*Learn how to better mimic fresh pasture grass when horses have little access to it! Ensure that these three nutrients are adequately supplied by the diet especially in the winter months.

Winter time for horses in the Northern US means little to no pasture access and complete hay-based diets. So, one of the ways to think about winter feeding is to think about replacing those nutrients horses would normally get from fresh pasture grass. This could also be the case for horses who get hay all year round. If you want to make your horse really "pop" when they shed out next spring, ensure that these three nutrients are well supplied in the supplemental diet.

I know that you are all excited to know which three "magic" ingredients I'm going to list off, but first, I want to address the OVERWHELMING importance of fiber and water. It's kinda like telling a child to eat their fruits and veggies, but it bears repeating. If you have not already read "10 Tips for Surviving Sub-Zero Temperatures with Horses", you may want to peruse that first- especially tips #1, #7-9! Fiber, a.k.a. structural carbohydrates, are what keeps horses warm in inclement weather and good water consumption is absolutely critical for fiber digestion and colic prevention, so I'm going to assume that those two nutrient categories are well covered. Fiber and water are the basics that make the next three nutrients relevant.



Vitamin E is most commonly known as an antioxidant and is very important for cell membrane function. We know it to be critically important for muscle health in horses. Vitamin E is naturally found at high levels in fresh, green grass, but deteriorates quickly in stored foraged. According to the NRC (2007) 54-73% of the vitamin E found in alfalfa hay at harvest will be lost in just 12 weeks! Therefore, it's important to ensure adequate levels of this nutrient especially in winter!

The average 1,100 lb horse in moderate work only requires about 700-2,200 IUs of Vitamin E per day according the 5th revision of the NRC, but I like to ensure that all working horses are getting 3,000 IUs in their daily diet. That is a total from all forage, feed and supplement sources. A typical ration balancer will supply about 600-1,000 IU/lb so a little extra from a supplement may be warranted. You can check out my review of several good Vitamin E supplements at Rate My Horse Supplement website. CLICK HERE.


Anther nutrient to consider adding in winter is Omega-3 (n-3 fatty acids). These are a category of fatty acids known to moderate many types of inflammation. Like vitamin E, omega-3's are relatively high in pasture grass, but deteriorate over storage time. I think there is sufficient research evidence to suggest adding an omega-3 source to your horses' diets especially in the presence of allergies, myopathy and/or laminitis. It's also an excellent nutraceutical to add in the case of elite, hard working sport horses where stress is a constant. I personally will add the HorseGuard's Flaxen Flow to my horses' diets when I feel that their immune system may be taxed. The Flaxen Flow is a potent cold, pressed form of flax seed oil for a great price. You can check out more of why I chose this supplement at Rate My Horse Supplement- CLICK HERE.

Omega-3 fatty acids are not typically added to fortified feed products, so they must be added in supplement forms. There are two general "types" of omega-3 supplements out on the equine marketplace; seed oil based supplements with high levels of alpha-linolenic acid such as that found in flaxseed and marine based supplements with high eicosapentaenoic acid and docosahexaenoic acid (EPA/DHA) levels (i.e. fish oils and algea). Which one you choose depends on your nutrition goals and how much you want to spend.

Now, the major disadvantage of adding any omega-3 supplement is cost- they will ALWAYS be expensive. You can count on any decent quality omega-3 supplement costing an additional $0.76 to $2.50 per day to feed (marine sources are usually more expensive). It can also be messy and inconvenient to add seeing as most are in liquid form. I don't think that EVERY horse needs an omega-3 supplement in wintertime, but it could be helpful in cases of disease and high performance.


Finally, I'd like to address the importance of adequate, good quality protein in winter diets. The protein/amino acid levels of immature grass hay is very high in the spring and early summer and then starts to drop off as the grass matures and then goes dormant for winter. If you are feeding a LOCAL grass hay (any species of cool-season grass that grows in your region) harvested past it's prime, it's likely that your hard working horse's protein intake is marginal at best or deficient at worst.

If your horse is very young, very old, or you ride your horse throughout the winter and all you have available is an untested grass hay, you might consider increasing the protein level of the diet. A simple forage first approach is to replace 15-25% of the grass hay with alfalfa hay especially if the horse needs the calories (nope, a couple pounds of alfalfa pellets won't cut it). Another simple way to add good quality amino acids is a ration balancer especially for easy keepers. Yes, reason #101 for feeding a ration balancer! Seriously, you just can't go wrong with these types of products! However, it's important that you do not double up on your horse's vitamin/mineral intake by adding a ration balancer, so check that your other supplements do not already contain a complete vitamin/mineral package. Do not, for instance, feed a ration balancer PLUS HorseGuard, Platinum Performance Equine, Vermont Blend, Cal Trace, or NW Supplement too.

Again, not all horses needed supplemental protein in their diet, but I have found many marginal or deficient protein diets recently in clients’ horse diets. Protein supplementation is extra important for young growing horses, geriatric horses, and heavily worked sport horses on all grass hay diets. If you are not seeing the "bloom" or feeling the "performance" you think your horse has within, you might consider scheduling a FREE 15 Minute Discovery Call to ensure adequate protein levels. You can also check out a couple protein supplement reviews HERE at Rate My Horse Supplement. Just be sure the protein supplement contains significant levels of the amino acids lysine, methionine and threonine.


And there you have it- three nutrients that could be lacking in hay based diets during winter months. Your horse may require supplementation of these nutrients due to their deterioration in stored forages over time. Without constant access to good quality pasture grass, it's likely that your sport horse needs some nutraceutical assistance in the areas of vitamin E, fatty acids and amino acids (protein). It's a simple matter of mimicking what nature intended. In the spring and summer, if your horse is lucky enough to have access to green grass, then by all means you can remove these supplements and save some money. No need to pay for them when they are already rich in pasture!

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