Fertility Outcomes in Lohi Sheep: A Comparative Study of Laparoscopic Versus Trans-Cervical AI With Frozen-Thawed Semen Under Subtropical Conditions.

Efficient use of frozen-thawed semen in sheep is limited by low fertility following cervical insemination (CAI), whereas laparoscopic insemination (LAI) offers higher success but requires specialised skills and equipment. The current study aimed to evaluate the fertility outcomes of two artificial insemination techniques, laparoscopic and transcervical, in Lohi sheep using frozen-thawed semen. Lohi ewes (n = 44) were synchronised through progestin-sponges (day 0-day 11), administering PGF2α (d-cloprostenol 75 μg/mL; i.m @ 75 μg/ewe) on day 09 and eCG (i.m @ 300 IU/ewe) on day 11. Synchronised ewes (n = 44) were divided into two groups for artificial insemination (AI) procedures: cervical (CAI; n = 24; sperm concentration = 200 million/dose) and laparoscopic (LAI; n = 20; sperm concentration = 50 million/dose). All ewes were inseminated at 54 h post-sponge removal. Results of the experiment revealed that LAI demonstrated higher pregnancy rates (65%) than CAI (33.3%) (p = 0.05). However, no significant differences were observed in prolificacy or twinning rates between the two techniques (p = 0.11). In conclusion, LAI as compared to CAI is a superior method of insemination for achieving optimum pregnancy rates in estrous synchronised Lohi ewes.