Transcervical AI in Sheep: An Overview

Within sheep industry artificial insemination (AI) is a very valuable tool for rapid genetic progress. Besides, AI is performed to maximise the use of superior rams and contain certain contagious diseases within flocks. In the sheep breeding industry three methods of AI are prevalent: vaginal, cervical and laparoscopic intrauterine. Commercially acceptable fertility rates, however, can be achieved by laparoscopic intrauterine insemination using both fresh and cryopreserved semen but with cervical AI using fresh semen only. The most successful method, therefore, seems to be Laparoscopic AI but it is an expensive, invasive surgical procedure and is not considered to be welfare-friendly. A practical solution is, therefore, transcervical intrauterine (TCAI). However, due to the convoluted nature of the cervix, penetration of the inseminating pipette to enable TCAI is rarely achievable. This review describes some of the work that has been done to understand the mechanism(s) of cervical relaxation with the ultimate objective of performing transcervical AI in sheep.

Keywords:

Trans-cervical Artificial Insemination, Sheep Cervical relaxation,

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Kershaw-Young CM, Khalid M, McGowan MR, Pitsillides AA, Scaramuzzi RJ. 2009. The mRNA expression of prostaglandin E receptors EP2 and EP4 and the changes in glycosaminoglycans in the sheep cervix during the estrous cycle. Theriogenology, 72: 251-261. doi: 10.1016/j.theriogenology.2009.02.018.
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