How to Evaluate a Probiotic
You’ve probably heard a lot about probiotics and the benefits they provide to horses. When used in appropriate circumstances with an effective protocol, probiotics have proven to be quite beneficial. So how do you know if you’re using an effective protocol? Triple Crown nutritionist, Dr. Bill Vandergrift, shares some recent studies to inform just how effective our probiotic protocol is.
Four things horse owners should know when it comes to evaluating probiotics are:
1. Probiotic strain and dose matter
University of Kentucky research
University of Kentucky researchers compared three Lactobacillus strains individually, as well as a mixture of all three strains, in their ability to change the microbiome in equines. Lactobacillus acidophilus, Lactobacillus reuteri and Lactobacillus buchneri were each dosed at 1 billion colony-forming units (CFUs) in an equine in vitro trial.
Researchers found that L. acidophilus and L. reuteri were more effective at increasing pH, increasing lactic acid-utilizing bacteria, and decreasing starch-utilizing bacteria compared to L. buchneri.
In plain speak, that means L. acidophilus and L. reuteri are more effective probiotics than L. buchneri. Interestingly, the ability of all three strains to alter the equine microbiome when combined in equal amounts to provide a total of 1 billion CFUs was significantly less than any of the three individual strains dosed separately at 1 billion CFUs each.
This research illustrates two major points:
- Each individual probiotic strain must supply a minimum of 1 billion CFUs to be effective. Products that combine multiple probiotic strains where each individual probiotic strain contributes less than 1 billion CFUs do not effectively alter the equine microbiome — even if the sum of all individual probiotic strains combined is greater than 1 billion CFUs.
- Not all probiotic strains effectively change the equine microbiome, even when dosed at 1 billion CFUs or more.
Ohio State University research
Ohio State University researchers conducted a two-part study to evaluate a commercial probiotic in horses.
In the first part of the study, a commercial probiotic supplying 1 billion CFUs of L. acidophilus was given to mature quarter-horse mares via top dress on a standard hay and grain diet. This probiotic significantly altered the microbiome as measured by microbial rRNA markers.
In the second part of the study, a commercial probiotic supplying 10 million CFUs of L. acidophilus was given to growing quarter-horse mares via top dress on a standard hay and grain diet. This probiotic had no effect on the microbiome as measured by microbial rRNA markers.
The results of this study indicate that:
- L. acidophilus can significantly alter the microbiome in mature horses.
- Concurring with results from University of Kentucky research, acidophilus should be dosed at 1 billion CFUs or greater in order to effectively alter the microbiome in growing or mature horses.
2. Some dead probiotics are as effective as live probiotics
University of Kentucky researchers also investigated the effect of dosing the equivalent of 1 billion CFUs of live L. reuteri versus equal amounts of autoclaved or dead L. reuteri. Both treatments significantly altered the microbiome but there was no difference between the effectiveness of live and dead L. reuteri. Upon further investigation the researchers determined that the “probiotic effect” of L. reuteri was due to unique peptides found in the cellular membrane of L. reuteri, indicating that this particular probiotic strain could be dosed dead or alive to achieve the same benefit.
3. Prebiotics make probiotics more effective
Let’s summarize the three main takeaways regarding probiotics so far:
- Not all probiotic strains are effective at altering the microbiome.
- Most probiotics require at least 1 billion CFUs per day to be effective.
- At least some probiotic strains are equally effective when dosed either dead or alive.
So how can we make effective probiotic strains even more effective? Dosing probiotics in combination with prebiotics has been proven through multiple research and clinical studies to increase the beneficial effects of probiotics.
A probiotic is defined as a bacteria strain that has a beneficial effect on the health of the digestive system, whereas a prebiotic is defined as an ingredient that serves as a food source for probiotics and/or provides a beneficial effect on the health of the digestive system. Therefore, when evaluating commercial probiotics, it is best to choose one that provides both prebiotic ingredients and probiotics.
4. All Triple Crown horse feeds contain EquiMix.
Why is that so important? EquiMix contains multiple pre- and probiotics in the form of direct fed microbials, yeast, mannan oligosaccharide (MOS) and mycotoxin protection:
- (Probiotics) Direct fed microbials now with a new patented strain of Bacillus subtilis shown to assist in protecting against “Clostridia”, survive stomach acid, and offer long term feed stability, along with Lactobacillus acidophilus and Enterococcus faecium that provide a minimum of 1 billion CFUs of each probiotic per day.
- (Prebiotics and probiotics) Now with a thermostable live yeast containing 25% more live cultures along with yeast metabolites, which help maintain a healthy microbial population in the hindgut.
- (Prebiotics) An improved food-grade MOS, which can help to inhibit the growth of pathogenic bacteria and support normal immune system function.
- (Prebiotics) Mycotoxin protection, which can aid in neutralizing various forms of mycotoxins commonly found in feed and hay.
Harlow, B.E., Lawrence, L.M., Kagan, I.A. Harris, P.A. and Flythe, M.D. Exogenous lactobacilli mitigate microbial changes associated with grain fermentation in vitro. J. Eq. Vet Sci. 2015, 35:400-417 (No. 38).
Barnhart, K, Reddish, J.M., and Cole, K. Supplementation with Lactobacillus acidophilus influences microbial diversity in the gastrointestinal tracts of healthy horses. J. Eq. Vet Sci. 2015, 35:400-47 (no. 68).
Patel, R., DuPont, H.L. New Approaches for Bacterotherapy: Prebiotics, New-Generation Probiotics, and Synbiotics. 2015. Clinical Infectious Diseases 60(S2):S108-121.