The efficacy of human recombinant luteinizing hormone for in vitro embryo production in sheep

Objective: This study was carried out to assess the ability of recombinant human luteinizing hormone (r-LH) to be used instead of sheep hypophyseal luteinizing hormone (h-LH) in the maturation of sheep oocytes and its influence on embryonic development and quality. Materials and Methods: The oocytes were obtained from slaughtered sheep ovaries. For maturation, oocytes (grade 1) were incubated at 38.5°C, 5% CO2 for 24 hours. 0.1 IU/ml LH (from sheep Piturity LH, Sigma®) was added to the culture media of the hypophyseal LH (h -LH) group and 0.1 IU/ml LH (Luveris® 75 IU, Serono) to the Recombinant LH (r-LH) group. In vitro fertilization (20h) and embryo culture were performed at 5% CO2, 5% O2 and 38.5°C incubation conditions. The maturation rates were reported based on the MII stage chromosomal formation and the existence of polar body by bisBenzimide (Hoechst 33342). Embryonic developments were controlled at 3rd and 8th day of in vitro culture. For the embryonic cell count and determination of inner cell mass (ICM) and trophectoderm cell (TC), the differential staining technique was used with Hoechst 33342 + Propidium Iodide (PI). Results: The proportion of cleavage (%), the rate of embryos developing the morula (%) and blastocyst stage (%), and the ICM, TC, and total cell numbers of the embryos were found to be statistically similar in the h-LH and r-LH groups. Conclusion: It was concluded that r-LH could be used as an alternative LH source instead of hypophyseal LH.