It would be amazing if there was a quick, easy, non-invasive way to determine if a horse’s nutrient requirements are being met by their diet. Bonus points if the test is also relatively inexpensive.

At first glance, Horse Hair Analysis seems to check all of these boxes. However, a test also needs to be reliable and repeatable to be effective. If we can’t rely on a diagnostic test to give accurate results, the best-case scenario is that we have wasted money that could otherwise go towards supporting our horse (or buying another saddle pad, no judgement).

The potential downsides are much higher in this scenario. The results from these tests are often used to make decisions on a horse’s diet, typically resulting in the supplementation of multiple individual nutrients. If an inaccurate or unreliable test leads to unnecessary supplementation of the diet with individual nutrients, there is the risk that you will create toxicities or nutrient imbalances that could negatively impact the health of your horse over time.

There have been multiple studies that have looked at the accuracy of hair analysis to predict the nutrient status of the horse and each have found the method to be lacking. One study found that the results differed considerably when submitting two samples of mane from a paint horse, one white and one black. Another study fed varying levels of calcium and found that this did not correlate to mane calcium levels when tested. When considering a diagnostic test, particularly one that is offered outside of veterinary oversight, it is important to confirm that the methodology is scientifically sound.   

Hair analysis does have specific uses in horses that have been extensively studied. Hair analysis can be reliably used to test for certain drugs because drug metabolites can be found in hair long after the drug has cleared the blood. These tests are utilized in the racing industry or may be offered as part of a pre-purchase exam package.

The attraction of horse hair analysis is that it would be a quick and easy evaluation of the nutritional status of your horse. Since this method isn’t reliable or accurate, we need to look at other options. Other options include blood testing, liver biopsy or feed analysis.

Blood testing is only accurate for select nutrients. This is because the body has mechanisms to maintain blood nutrient levels in very tight ranges in the blood. This is accomplished by pulling stores from other parts of the body. As a result, blood levels will only be out of the biological reference range when a horse is experiencing severe deficiency or toxicity and, in these horses, severe clinical symptoms would be evident.

Two nutrients that are reliably tested in the blood are Vitamin E and selenium. A caveat with selenium is that whole blood selenium should be tested. Whole blood selenium gives an accurate picture of the horse’s long-term selenium test. Plasma and serum selenium tests are sensitive to recent fluctuations, such as recently consumed meal.

The level of other minerals in the body can be reliably tested through a liver biopsy; however, this is an invasive diagnostic test that is not typically utilized outside of research settings.

The best way to determine if a horse’s diet is providing the nutrients they need is to evaluate the diet itself. A basic forage analysis is priced very reasonably and if you combine this information with the amount of forage fed and the tag values and amount of any feed or supplement fed, the total intake of each nutrient can be determined and compared against the published minimum requirements for the horse in the Nutrient Requirements for Horses (NRC, 2007).

Generally, unless a horse has an underlying health condition or the quality of the hay is very poor, a commercial feed being fed at or above the minimum recommended rate for your horse’s size and level of work will provide all of the nutrients a horse requires.

Not sure if your horse’s diet is nutritionally complete? Our team would love to help you with a free, personalized feeding plain tailored to your horse’s specific needs. Contact us today!
 

Nicole Rambo, Ph.D.