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Good Bugs Vs. Colic

The American Association of Equine Practitioners fields a question about the benefits of feeding live bacterial cultures to your horse.

Journal photo.


Do live bacterial cultures help to decrease colic? Should I continue feeding this during the spring and summer?


Live bacterial cultures are also known as direct-fed micro-organisms or probiotics. They're the "good bugs," and have names like Lactobacillus, Enterococcus, Bifidobacterium and Bacillus. Aspergillus, a fungus, and Saccharomyces, a yeast, are also considered probiotics. Nutritionists define them as "live micro-organisms, which when administered in adequate amounts, confer a health benefit on the host."

Some of these health benefits include: making B vitamins, producing energy, suppressing "bad bugs" and supporting the immune system. That is, they help maintain a healthy digestive tract and help the host extract the most nutrition possible out of the diet.

Although probiotics are used quite frequently in horses (as well as humans and pets), we are just now beginning to see good scientific research to support their use. For example, the yeast Saccharomyces has been shown to increase the digestibility of fiber in the diet, improving milk quality in mares and enhancing growth in young horses.

By digesting the higher levels of cellulose and hemicellulose in poor-quality hay, Saccharomyces might play a role in preventing digestive disorders associated with hay that is too coarse for the horse to digest himself.

Supplementing with Saccharomyces has also been shown to allow some horses to better tolerate high sugar/starch diets without developing digestive disorders such as colic or hind-gut acidosis (too-low pH values in the cecum and colon).

-- Dr. Lydia Gray, American Association of Equine Practitioners

*AQHA and the provider of this information are not liable for the inherent risks of equine activities. We always recommend consulting a qualified veterinarian and/or an AQHA Professional Horseman.