Acute Endometritis due to Taylorella equigenitalis Transmission by Insemination of Cryopreserved Stallion Semen.

This study shows that the bacterium Taylorella equigenitalis, which can cause infection in horses, can be transmitted through artificial insemination using cryopreserved (frozen) stallion semen, highlighting the need for thorough screening of semen before use.

Background on T. equigenitalis

• Taylorella equigenitalis is a bacteria known for causing contagious equine metritis, a highly infectious disease in horses that causes inflammation of the uterus (endometritis) and can lead to infertility.
• While the bacteria can be transmitted through sexual contact between horses, it’s also known to be transmitted during artificial insemination – a procedure where semen is collected from a stallion and then manually inserted into the mare’s uterus.

Transmission through cryopreserved semen

• Accumulating evidence suggests that cryopreservation of semen – a process involving the freezing and storage of semen for future use – does not eliminate the risk of T. equigenitalis transmission.
• In this report, the authors describe a clinical case of T. equigenitalis transmission by cryopreserved stallion semen. The same strain of T. equigenitalis was recovered from a mare’s vaginal discharge and from the batch of the cryopreserved semen that was used for insemination.
• The strain of T. equigenitalis found in this case was identified as ST-46, which is known to circulate in the country where the semen was collected.

Importance of screening semen

• The findings of the report underline the importance of thorough screening of processed semen before it’s used for artificial insemination. Specifically, the authors recommend screening for contagious equine metritis to prevent the transmission of T. equigenitalis.
• Strict screening measures are needed to prevent the introduction and spread of this potentially devastating disease among horse populations.

Conclusion and implications

• These findings have significant implications for horse breeding operations and artificial insemination protocols. The presence of T. equigenitalis in cryopreserved semen means that even stringent freezing procedures cannot necessarily eradicate the bacteria.
• This underscores the importance of routine microbiological control in semen processing and strict quarantine measures for imported semen to avoid cross-contamination and subsequent transmission of infectious agents.