Abstract:Objective To establish a simple method for germplasm storage of transgenic mice by vitrification.Methods Ethylene glycol(EG) was used as a cryoprotectant for embryo cryopreservation of HBV-C transgenic mice by vitrification.Results The best results of cryopreservation were obtained after using vitrification solution containing 30% EG.The developing percentage of thawed embryos were 81.54% and 69.81% of them developed to expanded blastocysts.Comparing recovered compacted morulae with blastocyst in expanded blastocysts percentage.the former were significantly better than the latter(78.95% vs 56.52%,P<0.05).Different methods of installation of the 0.25-ml plastic straw infulenced the recovery rate.When recovered embryos were transferred into pseudo-pregnant recipients,54.9% embryos developed to live offspring.Conclusion This method may be of practical use for embryos preservation of transgenic mice.