Studies on Transfer of Cow's Embryos Rapidly Frozen and Thawed

Abstract

Seven, 54, and 10 embryos were transferred to solution N₂ at-20, -30, and-36°C, respectively, and then thawed rapidly at-360°Cfmin. The storage medium used were DB+20-50% BS or FCS in case of-20 and-30°C, and Ringer's solution +30%BS in case of-36°C. They contained 1.0M and 1.25M glycerol, respectivery.
Of the 7 embryos in case of-20°C, only one survived and the others were regarded as degeneratire ones at 48 hours of culture.
Of the 54 and the 10 embryos in case of-30 an-36°C, 25 and 5 survived, suffering from limited damage at 2 and 24 hours of culture, respectively.
Cows became pregnant when 3 of the 20 and 2 of the 5 embryos in case of-30 and-36°C, respectively, were transplanted to them.