Updated October 13, 2006

Perennial Peanut Hay As A Roughage For Horses

Gary Heusner
Extension Animal Scientist - Equine

A number of horse owners and managers have been asking about perennial peanut hay as a hay source for horses. Perennial peanut hay should not be confused with "peanut hay" that is the aftermath from harvested peanuts. Perennial peanut is a high-quality persistent tropical forage legume which can be grazed or fed as a harvested hay. Limited research has been done to determine the digestibility of perennial peanut hay in the horse. Dr. Sandi Lieb and colleagues with the University of Florida in 1993 reported on some work comparing perennial peanut (Florigiaze variety), coastal bermudagrass, bahiagrass, and alfalfa hays. The results indicted that rhizomal perennial peanut hay is more closely equivalent to alfalfa than to the grass hays studied in nutrient content and digestibility. For this study the crude protein content, Neutral Detergent Fiber %, and digestible energy content are listed in Table 1 along with an estimated relative feeding value based on crude protein, neutral detergent fiber content, digestible energy, and expected acceptability. 

TABLE 1. Nutrient Contents and Relative Feed Values of

Hays Tested (100% Dry Matter Basis)

Comparing the nutrient contents of the hays, it is easy to see that based on the nutrients the two legumes (perennial peanut and alfalfa) are more similar in protein, fiber, and energy content. In this particular study there was a wide variation in the quality of the grass hays ( Bermuda and Bahia ). This is typical of hays that are produced and sold as horse hays. That is, there is a wide variation in nutrient content of hays due to stage of maturity, fertility and conditions of harvesting. The Estimated Relative Feeding Values are Based upon a high quality Alfalfa hay being assigned a value of 100 based on nutrient content and acceptability. Acceptability is defined loosely as how much a horse likes the hay and will consume when fed ad libitum (twenty-four access).

Table 2 provides nutrient contents and relative feeding values of hays based on nutrient and fiber contents. It was reported in the Florida study that the perennial peanut hay was actually consumed at higher rates than the other hays. Peanut hay was consumed at the rate of 3.18% of the horses' body weight whereas alfalfa was consumed at 2.45%, Bermudagrass 2.77%, and Bahiagrass 1.55% of the horses' body weight.

The bottom line is that Perennial Peanut Hays is a legume that will work very well as a forage source for horses. Caution must be used when switching to peanut hay from a grass hay. Horses should be gradually switched over to prevent digestive disturbances just like any change in feed should be made over a period of seven to ten days. 

TABLE 2. Relative feeding values of hays for horses

(100% DM basis)