The Vaginal Microbiome of Mares on the Post-Foaling Day Under Field Conditions.
Authors: Płoneczka-Janeczko Katarzyna, Magdziarz Marcin, Siemieniuch-Tartanus Marta
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Within 12 hours of natural delivery, researchers characterised the vaginal microbiome of six mares using next-generation sequencing, identifying 33 bacterial species across 25 genera to establish a baseline understanding of the immediate postpartum microbial environment. The dominant bacterial families were Leptotrichiaceae (21.72%), Peptostreptococcaceae/Tisserellales (15.54%), and Corynebacteriaceae (13.32%), with consistent core species including *Corynebacterium kutsheri*, *Campylobacter* spp., and *Facklamia* spp. present across all samples. Notably, several *Corynebacterium* and *Streptococcus* species identified in these early postpartum samples have previously been implicated in uterine infections, raising questions about whether they represent normal commensal colonisation or pathogenic colonisation during this critical window. For equine practitioners, these findings underscore the importance of understanding the natural vaginal bacterial landscape in healthy mares immediately after foaling—knowledge essential for differentiating pathological from physiological microbial profiles and for interpreting culture results when postpartum complications arise in either mare or foal. Further longitudinal work tracking how these microbial communities evolve during the postpartum period, and their relationships to neonatal health outcomes, is needed to translate these baseline data into actionable clinical guidance.
Read the full abstract on PubMed
Practical Takeaways
- •Understanding the normal vaginal microbiome composition within 12 hours post-foaling establishes a baseline for identifying abnormal or pathogenic microbiota patterns in mares with postpartum complications
- •The presence of potentially pathogenic bacteria (Corynebacterium, Streptococcus species) in healthy post-foaling mares suggests careful monitoring is warranted to distinguish colonization from infection in postpartum disease
- •Neonatal foals acquire maternal vaginal bacteria during delivery; characterizing this microbiota transfer is important for understanding foal immune development and susceptibility to early infections
Key Findings
- •Post-delivery vaginal microbiome of mares comprised 18 families, 25 genera, and 33 bacterial species identified via next-generation sequencing
- •Core bacterial families included Leptotrichiaceae (21.72%), Peptostreptococcaceae/Tisserellales (15.54%), Corynebacteriaceae (13.32%), Aerococcaceae (10.84%), and Campylobacteraceae (4.26%)
- •Shared bacterial species across mares included Corynebacterium kutsheri, Campylobacter spp., Facklamia spp., and Oceanivirga uncultured bacteria
- •Various Corynebacterium and Streptococcus species identified that could potentially be involved in uterine disorders in postpartum mares