Screening of the equine intestinal microflora for potential probiotic organisms.
Authors: Weese J S, Anderson M E C, Lowe A, Penno R, da Costa T M, Button L, Goth K C
Journal: Equine veterinary journal
Summary
# Editorial Summary The application of probiotics in equine practice remains hampered by a lack of evidence demonstrating clinical efficacy—a gap that may stem from the use of organisms not naturally adapted to the equine gastrointestinal tract. Weese and colleagues isolated and screened lactic acid bacteria cultured directly from healthy horse faeces, selecting for strains exhibiting antimicrobial properties, acid tolerance, and adherence capabilities—characteristics considered essential for effective colonisation and therapeutic action within the equine intestine. Their screening process successfully identified equine-origin isolates with these predetermined beneficial traits, providing a foundation for future probiotic development rather than relying on organisms selected from other species or without validated mechanisms of action. The significance of this work lies in shifting probiotic selection methodology away from generic commercial strains towards organisms inherently suited to the equine microbiome, potentially explaining why conventional probiotics have failed to demonstrate measurable health benefits in horses. For farriers, vets, and nutritionists recommending digestive supplements, these findings suggest that future probiotic efficacy may depend critically on strain selection and origin—underscoring the need for evidence-based products specifically developed from equine sources rather than products formulated for other species.
Read the full abstract on PubMed
Practical Takeaways
- •Existing probiotic products may be ineffective in horses because they lack organisms naturally adapted to equine gut ecology—look for species-specific formulations
- •Future probiotic selection should prioritize bacteria isolated from healthy horse intestines rather than generic or bovine-origin strains
- •Until better-validated equine probiotics are available, focus on management practices (forage quality, water access, stress reduction) with proven benefit to intestinal health
Key Findings
- •Probiotics have not demonstrated beneficial health effects in horses, possibly due to improper selection of probiotic organisms
- •Study identified lactic acid bacteria of equine origin as candidates for therapeutic probiotic development
- •Screening process focused on selecting organisms with predetermined beneficial properties specific to equine intestinal microflora