New Research on Probiotic Supplements for Performance Horses

Lactobacillus spp.—well-known constituents of the equine microbiome and common ingredients in probiotics—benefit animals by improving insulin sensitivity; acting as an anti-inflammatory, antioxidant, and antimicrobial agent; and even inducing cancer cell death. According to a recently published study* by a group of Taiwanese researchers, supplementation with the probiotic bacterium Lactobacillus plantarum may have additional benefits for performance horses.

“This preliminary study shows that dietary supplementation with L. plantarum increased muscle mass and potential for athletic performance, as the number of type I slow-twitch muscle fibers was increased in a model using mice,” shared Kathleen Crandell, Ph.D., an equine nutritionist for Kentucky Equine Research (KER).

The rationale for using probiotic Lactobacillus spp. to help athleticism and performance is straightforward:

1. Exercise requires energy in the form of ATP (adenosine triphosphate);
2. Microbes in the hindgut ferment feedstuffs to produce short-chain fatty acids, such as butyrate; and
3. Butyrate generated in the hindgut from probiotic bacteria such as Lactobacillus spp. is used by the exercising animal in a complicated sequence of events that ultimately generates ATP.

The researchers further suggest that Lactobacillus bacteria may actually facilitate the “energy-harvesting capacity” of an exercising animal.

To demonstrate the athletic benefits of L. plantarum, Chen and colleagues supplemented the diets of three groups of mice with the bacteria. After six weeks, they found a dose-dependent increase in physiological changes beneficial to animals during and after intense exercise (e.g., decreased serum lactate, ammonia, creatine kinase, and glucose).

Based on these positive data, the researchers concluded that “long-term supplementation with LP10 [L. plantarum] may increase muscle mass, enhance energy harvesting, and have health-promotion, performance-improvement, and anti-fatigue effects.”

More research is necessary to demonstrate safety and efficacy in horses. In the meantime, a well-balanced diet with supplemental probiotics may be helping our horses more than we previously realized.

*Chen, Y-M., L. Wei, Y-S. Chiu, et al. 2016. Lactobacillus plantarum TMK10 supplementation improves exercise performance and increases muscle mass in mice. Nutrients. 8:205.