Effects of culture media conditions on production of eggs fertilized in vitro of embryos derived from ovary of high grade Hanwoo.

BACKGROUND: This study was investigated the effects of culture media conditions on production of eggs fertilized in vitro of embryos from ovaries of high grade Korean native cow, Hanwoo.

METHODS: The IVMD 101 and IVF 100 were used for in vitro maturation of selected Hanwoo oocytes and In vitro embryo culture after in vitro fertilization, respectively. The IVMD 101 and IVD 101 were used for in vitro culture and completely free of serum.

RESULTS: The cleavage rates of 2-cell embryos in reference to Hanwoo oocytes were 86.7, 92.9 , and 90.1 % in the control group, IVDM101 medium and IVD101 medium, respectively which indicates that the IVDM101 medium and IVD101 medium may result favorable outcomes. The in vitro development rates of blastocysts were 12.4, 38.4 and 32.4 % in the control group, serum free IVMD101 medium and IVD101 medium, respectively. For hatched blastocysts, it was 5.3, 33.9, and 28.6 % in the control group, serum free IVMD101 medium and IVD101 medium, respectively. Hence, more favorable results were expected for the hatched blastocysts in which the IVMD101 medium and IVD101 medium were used than the control group. Average cell numbers of blastocysts were 128.3, 165.7, and 163.6 in the groups of TCM-199 + 10 % FBS medium, IVMD 101 medium, and IVD 101 medium, respectively which clearly show that the IVMD 101 and IVD 101 medium consequence significantly higher cell numbers compared to the control group (i.e., TCM-199 + 10 % FBS medium). Pregnancy rate after embryo transfer was 39.6 % when the serum free medium was used which is higher than that of the medium supplemented with serum (32.8 %). In addition, stillbirth rates were 4.9 % in the group of serum free medium whereas it was 13.6 % in the serum supplemented medium (13.6 %).

CONCLUSIONS: Taken altogether, serum free media, the IVMD 101 and IVD 101 represented more favorable results in the embryo development rate of embryos, cell numbers of blastocyst, and pregnancy rate. Of note, the IVMD 101 medium showed better outcomes hence, it might be a better option for future applications for in vitro culture of bovine embryos.