In Vitro Evaluation of the Effect of Storage at -20°C and Proximal Gastrointestinal Conditions on Viability of Equine Fecal Microbiota Transplant.
Authors: Kopper Jamie J, Alexander Trevor L, Kogan Clark J, Berreta Ana R, Burbick Claire R
Journal: Journal of equine veterinary science
Summary
# Editorial Summary: Storage and Viability of Equine Fecal Microbiota Transplants Fecal microbiota transplantation (FMT) shows promise for treating equine intestinal dysbiosis, yet standardised protocols for preparation and storage remain underdeveloped in veterinary practice. Kopper and colleagues cultured manure-prepared FMT samples under two conditions: frozen storage at −20°C for up to four weeks, and exposure to simulated proximal gastrointestinal environments (acidic pH and bile salts), measuring microbial viability through culture-based techniques and microbial community composition. Freezing beyond one week significantly compromised microbial viability, whilst simulated gastric and biliary passage caused substantial population collapse—with gram-negative enteric bacteria proving particularly vulnerable to both stressors. These findings suggest that practitioners currently using frozen FMT preparations stored longer than seven days may be administering considerably diminished microbial loads, potentially undermining therapeutic efficacy, and highlight the need for further research into cryoprotectants, alternative preservation methods, or timing of FMT administration relative to feed and gastric pH to maximise bacterial survival.
Read the full abstract on PubMed
Practical Takeaways
- •Fresh FMT material should be used within 1 week of preparation if stored at -20°C; longer storage times compromise bacterial viability in equine applications
- •Practitioners should consider protective measures or alternative delivery methods to shield FMT from proximal GI tract conditions, as current exposure significantly reduces effectiveness
- •Further research is needed before recommending specific best-practice protocols for equine FMT storage and administration in clinical practice
Key Findings
- •Storage of manure-prepared FMT at -20°C for greater than 1 week significantly decreased microbial viability
- •Exposure to simulated proximal gastrointestinal tract conditions significantly reduced viability of the microbial population
- •Gram-negative enteric bacteria were most significantly impacted by both storage and GI conditions
- •Current storage and handling practices may compromise the efficacy of equine FMT