Kentucky Performance Products: What Nutrient Values Should I Consider When Testing Hay for My Metabolic Horse?

If you’ve ever had your hay tested, you know there is a lot to consider. Here is what to look for if you’re testing for a horse with a metabolic disorder.


Question: I have a horse that has Cushing’s and IR. The farmer is having the hay tested. I know that the sugar should be 10-12 % range. However what other values should I be looking at. I am wondering if this grass hay will meet my horse’s nutritional requirements?

Answer: Great question. The quality of hay is judged by its fiber and protein content. As the grass matures, the fiber levels increase and the protein decreases. NDF (neutral detergent fiber) and ADF (acid detergent fiber) are the tests used to determine the level of fiber in a forage. NDF is a more complete fiber fraction so it will always be represented with a high number.

Look for an NDF between 40% and 65% and an ADF between 30% and 45%. An ideal hay for easy keepers will be in the higher end of these ranges. If the hay has an NDF above 65% and an ADF above 45% it will provide little nutrient value for a horse.

Protein in hay varies depending on the type and maturity level of the hay when it is cut. Legume hays (alfalfa and clover) contain 12% to 20% protein; grass hays contain 6% to 10% protein. A mature horse requires at least 10% protein.

Once grass is cut and dried for hay, vitamins quickly lose their potency. This is particularly true for natural vitamin E. Depending on the area you live in, your hay may also lack some of the minerals your horse needs to remain healthy. For example, the northern and southeastern states in the USA are typically deficient in selenium.

To fill in the gaps in your horse’s diet we recommend you supplement with a well-balanced vitamin and mineral supplement like Micro-Phase. Micro-Phase provides the vitamins and minerals typically lacking in a diet consisting of mostly forages and little to no fortified grains.

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