Authors: Lucassen Alexandra, Hankel Julia, Finkler-Schade Christa, Osbelt Lisa, Strowig Till, Visscher Christian, Schuberth Hans-Joachim
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Saccharomyces cerevisiae fermentation products (SCFP) are marketed as immune-modulating supplements in equine nutrition, yet their effects on the gut microbiome remain poorly characterised. Lucassen and colleagues investigated this claim by supplementing six racehorses with Olimond BB (an SCFP product) and five controls with placebo for 43 days, analysing faecal microbiota via 16S rRNA sequencing and measuring circulating immune cell populations by flow cytometry. Rather than demonstrating a robust prebiotic effect, the study found that individual animal variation dominated microbiota composition throughout the trial, with no consistent differences between supplemented and control groups during the feeding period. Interestingly, one day post-vaccination against equine influenza, the alpha diversity of faecal microbiota differed significantly between groups, suggesting the SCFP may have modulated the immune response to vaccination in ways that indirectly affected microbial diversity—though this effect was neither sustained nor predictable. For practitioners considering SCFP supplementation, these findings temper expectations: whilst such products may influence specific immune events, evidence for a meaningful, consistent prebiotic action in racehorses is currently lacking, and individual variation appears to be a far more significant driver of microbiota composition than the supplement itself.
Read the full abstract on PubMed
Practical Takeaways
- •Olimond BB does not appear to substantially modify gut microbiota in racehorses during normal feeding conditions, limiting claims about prebiotic efficacy
- •SCFP may subtly influence the immune-mediated response to vaccination in ways that affect gut microbiota diversity, though the practical significance remains unclear
- •Individual horse variation is a major factor in microbiota composition—focus on other management factors rather than relying on this supplement for microbiota modification
Key Findings
- •SCFP supplementation (Olimond BB) did not produce consistent changes in fecal microbiota composition compared to placebo over 43 days of feeding
- •Individual animal variation had greater impact on microbiota composition than treatment group assignment
- •One day post-booster vaccination, placebo horses showed significantly higher alpha diversity of fecal microbiota compared to SCFP-supplemented horses
- •Circulating blood leukocyte subpopulation numbers changed similarly over time in both SCFP and placebo groups