developmental potetial of mouse morula early and late blastocyst after vitrification

introduction: the objective of this study was to assess developmental potential of mouse morulae, early and laic blastocysts after vitrification in r2 and r2+vero mediums. material and methods: morulae, early and late blastocysts were obtained from superovulated nmri female mice. embryos in experimental group were suspended in a solution of ethylene glycol, ficoll and sucrose (efs40) for 2 minutes and were then loaded into 0.25 ml straws, holding them on liquid nitrogen vapour for 3-5 minutes, finally were immersed into liquid nitrogen. embryos were thawed and equilibrated in 0.5 mol sucrose solution for 5 minutes, were cultured in r2 or r2+vero mediums for i 20 hours. results: results indicate high survival rate or embryos after vitrification (95, 85, 76% for morulae, early and late blastocysts respectively). sixty three, 70 and 75% in r2 and 67, 73, 80% in r2+vero reached to hatching and hatched blastocyst alter 4.s hours respectively for morulae, early and late blastocyst of control groups. while 24, 19 and 12% in r2, and 18, 22 and 16% in r2+vero of vitrified embryos were reached to hatching and hatched blastocyst after 4s hours. sixty five, 58 and 44% in r2 and 70, 63 and 56% in r2+vero of vitrified embryos following a delay of 48 hours on the 4th of cultivation day reached lo hatching and hatched blastocyst. conclusion: our results indicate that r2 and r2+vero have the identical property lo support development of vitrified and non-vitrified embryos. development of vitrified embryos show the same development competence comparing to control group alter a delay of 48 hours, from this statement we conclude that although vitrification damage the embryos inn most of these damage are reversible in a suitable medium is less expensive and more convenient than r2+vero.