Acute Endometritis due to Taylorella equigenitalis Transmission by Insemination of Cryopreserved Stallion Semen.
Authors: Delerue Marie, Breuil Marie-France, Duquesne Fabien, Bayon-Auboyer Marie-Hélène, Amenna-Bernard Nadia, Petry Sandrine
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), remains a significant concern in equine reproduction despite existing control protocols, particularly when artificial insemination is employed. This 2019 case report documents transmission of T. equigenitalis to a mare through cryopreserved semen, with molecular analysis—including API ZYM profiling, antibiotic susceptibility testing, and multilocus sequence typing (MLST)—confirming that the bacterial isolate recovered from the mare's vaginal discharge was genetically identical (ST-46 lineage) to organisms present in the implicated semen batch, establishing a direct epidemiological link. The finding is particularly concerning because cryopreservation is widely considered a risk mitigation strategy, yet this case demonstrates the organism's capacity to survive the freezing process and retain virulence, leading to acute endometritis in the recipient mare. The authors' evidence that the ST-46 lineage was known to be circulating in the semen collection region further underscores gaps in screening protocols. For equine practitioners involved in breeding programmes, this case reinforces the critical importance of rigorous pre-collection screening of stallions and post-thaw bacteriological testing of semen batches before use, particularly in international or high-value breeding contexts where documentation of CEM-free status cannot be definitively assured.
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Practical Takeaways
- •Strict screening protocols for Taylorella equigenitalis must be implemented before using any processed or cryopreserved semen for artificial insemination to prevent transmission of contagious equine metritis
- •Practitioners should verify that semen suppliers have robust contagious equine metritis testing procedures in place, regardless of whether semen is fresh or cryopreserved
- •If mares develop acute endometritis following insemination, consider Taylorella equigenitalis as a potential cause and screen both the mare and the semen source
Key Findings
- •Taylorella equigenitalis was successfully transmitted to a mare via artificial insemination using cryopreserved stallion semen
- •Isolates from mare's vaginal discharge and semen batch were identical by API ZYM, antibiotic susceptibility, and multilocus sequence typing (ST-46)
- •The ST-46 lineage identified is known to circulate in the country where semen was collected
- •This case demonstrates the risk of contagious equine metritis transmission through processed semen when inadequate screening occurs