Omega 6 and Omega 3 Ratio in an Equine Diet

As more horse owners gain understanding about nutrition in the human body, there are always those who would consider the value of applying that new understanding to the horse. There are times when this is a good thing. I feel that, where the value of Omega 6 and Omega 3 essential fatty acids is concerned, this may be one of those times. While it is important to point out that the amount of significant clinical testing on Omega 3 supplementation to horses has been limited, there are some basic points that deserve consideration. In the testing that has been done, It appears that the ratio between Omega 6 and Omega 3 in the diet can have a significant impact on horse health.  Each functions differently, and deserves a closer look.

 Omega 6’s can promote inflammation in a horses' body. While this may seem like a bad thing, there are situations where inflammation is of value, even necessary. When tissue is damaged, the resulting acute inflammation creates an increase in blood flow to the area in addition to an immune system response when needed. This is where healing can start, and potential infection can be fought. Without acute inflammation, the healing process could be much slower. Here we see value, even need, in the presence of Omega 6’s. Chronic inflammation on the other hand, is another matter. We often see chronic inflammation result from structural changes due to old joint, ligament or bone damage. Here is a place where we do not want Omega 6’s to influence inflammation, since it can contribute to chronic pain, not healing. I guess you could say that this is a snapshot of the good and bad of Omega 6’s, but don’t be confused, Omega 6s are vital in the horses body.

So, how do Omega 3’s influence the inflammation mentioned above? While clinical research on anti-inflammatory response in horses is minimal, anecdotal evidence seems to point strongly to possible reductions in chronic inflammation when Omega 3 fatty acids are at a level in the entire feeding program that is close to a 1 to 1.5 or greater ratio. (For the purpose of this article, the ratio will be expressed with Omega 6 first and Omega 3 second). This has led many people to question Omega 3 fatty acid levels in their horses’ diet. The real questions should be do I need more? If I do, how do I add it?  And, how much do I add?

When an issue that affects a horses health through diet is brought up, my first instinct is to go back to how the digestive system of the modern horse evolved. A free ranging wild horse basically ate what he stood upon. If an area had adequate nutrition in the available food sources the horses thrived, if not, disappeared from the area. Food available where wild horses thrive will be a mix of younger growing forage and older mature forage that has gone to seed. This blend of available food sources can give us a broad idea of what a normal Omega ratio should be.  In general, the growing forage will be somewhat higher in Omega 3’s, while the mature, dryer forage will likely have a higher Omega 6 level.  When all this is added together, the usual result of the blend will be an Omega 6 to Omega 3 ratio of around 1 to 1.2. This ratio can vary some with the amount of young growing forage and its relationship to older mature forages in a given area. The younger the mix of forage in general, the higher the Omega 3 part of the relationship.

How does this translate to fed horses that are kept in stalls, pens and pasture? In general, a conventional feeding program will consist of cured hay, a grain based feed concentrate, and perhaps a mix of ration balancers and supplements. Older cured hay will typically be lower in Omega 3’s than pasture or freshly bailed hay. When you add grain based feeds to older hay at a typical recommended feeding rate of 4 to 8 pounds, the Omega 6 to Omega 3 ratio can swing deeply into an elevated Omega 6 number. Is there a negative health issue generated by this? That depends on the individual animal in question. A sound healthy horse seems to tolerate elevated Omega 6 levels better that a horse that is suffering from chronic inflammation due to structural changes from old injuries.

If you are unsure whether or not your feeding program is providing a proper Omega ratio, there are a few guidelines for this that might help you figure that out. If your horse has good pasture and hay available as the primary energy source in its’ diet, and any additional grain based feed is used at a rate below two pounds per feeding, it is most likely getting the amount of Omega 3s that it needs in a comfortable ratio to Omega 6s so that both can be of benefit. If on the other hand, you are feeding cured hay that is six months old along with a grain based feed ration that exceeds 2 pound per feeding, then the diet is likely significantly higher  in Omega 6 than Omega 3 and may benefit by being adjusted.

There are a number of ways that a low Omega 3 ratio can be adjusted in a horse’s diet. Adding a source of Flax oil is one of the most common. Fish oil and soybean oil are also good Omega 3 sources. These oils can certainly change the Omega ratio and can have value in the diet. However, if the ratio is wildly out of balance because of a very high feed concentrate inclusion, it is much easier to address this in another way. Replacing high Omega 6 grain based feed with higher fat supplement feeds or grain replacers can create an improved ratio.  Even though these products may still be higher in Omega 6 than Omega 3, most exhibit a closer omega ratio and so much less is fed, compared to grain based feeds, that the total Omega 6 contribution to the diet is greatly reduced. This change can lower the total Omega 6 amount to the point that the Omega 3 that is naturally occurring in the forage will create a more ideal overall ratio. This approach has other advantages to the overall management of the horse by eliminating a disruptive starch and sugar source, thereby reducing colic risk and moderating attitude problems. The potential change in mental attitude may then reduce warm up times, and, in turn, lower structural stress in young horses that generates some of the inflammation that everyone is so concerned about in the first place.

So, where does this leave us? Finding a natural beneficial balance of Omegas by providing good quality pasture as the primary energy source with a minimal amount of additional Omega 6 from concentrates would be the obvious first choice. If pasture is marginal, high quality hay of the freshest cutting can be used as additional forage along with a concentrate that is energy dense enough to still be of value when fed at low feed rates.  If pasture is not available at all, and only hay is used, the switch to a lower starch, higher fat concentrate that does the job at the lowest effective feed rate, in place of four or more pounds of grain based concentrate, would move the Omega ratio to a more balanced level and provide additional benefits to overall health and attitude. The least effective solution would be to add high Omega 3 content oils to a diet that is already very high in Omega 6 due to high grain based concentrates. While this may balance the Omega ratio, it still leaves the high starch and sugar levels in diet that may generate other health issues.

As with any complex issue, there can be more to modifying the diet than just adjusting the Omega ratio.  I mentioned at the beginning of this article that I have always felt that it is best to go back to how the horse evolved and what they could eat to produce needed energy during that evolution. This is how the digestive machine was developed in the horse. The closest we can come to matching this type of diet while still meeting the additional energy needs of the modern performance horse, the more efficient that horse will be. This gives the horse the best opportunity to live a long, healthy and productive life.