Comparative Results of Survival of Vitrified Biopsied Goat Embryos and Mouse Morulae

The purpose of this study was to find an efficient cryoprotectant and a suitable procedure for vitrification of mouse morulae. The method found with mouse morulae was then applied to the cryopreservation of biopsied goat embryos. Mouse morulae were exposed, in 1- or 2-step, to the ethylene glycol (EG)-based solutions EFS30 or EDFS30, which contained 30% EG and 15% EG plus 15% dimethylsulphoxide (DMSO), respectively, in phosphate buffer saline (PBS) containing 30% (w/v) Ficoll and 0.5 M sucrose, cooled in liquid nitrogen and warmed up rapidly. After warming, the rate of the hatched blastocyst formation in mouse morulae vitrified with EFS30 (54.0%) by the 2-step method was significantly higher compared to those vitrified with EFS30 (30.4%) and EDFS30 (27.7%) by the 1-step method (P < 0.05). According to those results, biopsied goat embryos were vitrified in EFS30 using the 2-step method. The results showed that the developmental blastocyst rate of the post-thawed embryos was 47.1%. It may be concluded that goat embryos were vitrified safely in an ethylene glycol-based solution (EFS30) by the 2-step method.