The present study was conducted to compare on embryo survival rates by blastomere isolation methods, and establish the optimal PCR procedure for perform the sexing of bovine blastocysts produced by IVF. IVF embryos used in the study was used the Bisected or Sliced methods for blastomere isolation, and the survival rates of blastocyst with rapid way of sexing PCR was assessed. In the present study for survival rates in blastocyst was the total cleavage rate was 75% and a blastocyst development among cleaved embryos was 40%. Survival rate of embryos treated with intact, bisected or sliced method was 100, 63.3 or 81.3%, respectively. Therefore, survival rate of embryos treated with sliced method was higher compared to that of embryos treated with bisected method. The sexing rate of female or male was not significantly different between S4BFBR primer and BSY + BSP primer (1.75 : 1 vs. 1.43 : 1), respectively. Because of the PCR amplification using the S4BFBR primer was simpler method than multiplex PCR amplification method. Furthermore, the accuracy of sexing rate and reduction of PCR work time between 2-step and 3-step of PCR methods was 98.0% / 1.5 hr and 97.0% / 3.5 hr, respectively. Based on these results, it can be suggested that the sliced and PCR methods we developed was very effective method to reduce time consuming and procedure of PCR amplification for sexing with the increase of survival rate on the blastocyst.

Keywords: bisection, blastocyst, bovine, S4BFBR primer, sexing