Yeast Culture

One of the most noted responses of yeast culture inclusion in horse diets is the positive impact on hindgut fermentation of fiber (cellulose and hemicellulose conversion to volatile fatty acids) which leads to better forage utilization and more energy production. Diets containing a performance-proven yeast culture are digested more completely, which positively affects the efficiency of forage utilization and horse performance. Yeast cultures have also improved nitrogen digestibility (better protein usage from forage) and digestibility of some minerals.

The Diamond V ProcessTM* used to manufacture yeast culture creates nutritional metabolites. A true yeast culture is an all-natural product derived from culturing Saccharomyces cerevisiae (yeast). During the culturing process, yeast produce nutritional metabolites which are products of yeast metabolic processes. These nutritional metabolites increase the fermenting activity of hindgut bacteria, enabling them to more completely break down the feed, providing the horse with additional nutrients for absorption. Digestion studies have shown Diamond V Yeast Culture increases fiber digestibility in the horse (see Figure 1). Therefore, nutrients in hay and feed are more available for use by the horse. By increasing the digestibility of fibrous feedstuffs, more energy is made available for growth, maintenance, or other activities.

The use of yeast culture has also been shown to influence the level of plasma lactic acid in exercising horses. Lower levels of plasma lactic acid were produced in exercising horses fed yeast culture compared to control (no yeast culture) horses (see Figure 3). Horses with lower lactic acid levels are capable of working longer and recovering quicker and have less risk of typing-up.

All horses can benefit from yeast culture supplementation. The level of response is dependent on forage quality and class of horse. Young horses, working horses, and broodmares in late gestation and early lactation particularly benefit from yeast culture supplementation. Yeast culture supplementation may also be beneficial to older horses, since they cannot digest protein, phosphorus, and fiber as efficiently as younger horses. Yeast culture seems to be especially valuable when forage quality is less than optimum, regardless of the class of horse being fed. Injured horses and horses recovering from illness also benefit from supplementation.