Open-pulled straw (OPS) vitrification of in vitro fertilised mouse embryos at various stages.
The present study was designed to investigate the cryotolerance of in vitro fertilised (IVF) mouse embryos at various preimplantation developmental stages. IVF mouse embryos were vitrified by the open-pulled straw (OPS) method. After warming, embryos were morphologically evaluated and assessed by their development to blastocysts, hatched blastocysts or term. The results showed that a high proportion (93.3-100.0%) of vitrified embryos at all developmental stages were morphologically normal after recovery. The developmental rate of vitrified 1-cell embryos to blastocyst (40.0%) or hatched blastocyst (32.7%) or term (9.3%) was significantly lower than that from other stages (P < 0.05). Vitrified embryos from 2-cell to early blastocyst stage showed similar blastocyst (71.8-89.5%) and hatched blastocyst rates (61.1-69.6%) and could develop to term without a significant loss of survival compared with those of fresh embryos (P > 0.05). Vitrified 2-cell embryos showed the highest survival rate in vivo (50.6%, 88/174), compared with that from other stages (9.3-30.5%, P < 0.05). The data demonstrate that the OPS method is suitable for the cryopreservation of IVF mouse embryos from 2-cell stage to early blastocyst stage without a significant loss of survival. Embryos at the 2-cell stage had the best tolerance for cryopreservation in the present study.
Yan
Chang-Liang
CL
College of Animal Science and Technology, China Agricultural University, Beijing, PR China.
Yang
Qi-En
QE
Zhou
Guang-Bin
GB
Hou
Yun-Peng
YP
Zhao
Xue-Ming
XM
Fan
Zhi-Qiang
ZQ
Liu
Man-Qing
MQ
Liu
Lin
L
Zhu
Shi-En
SE
D000818:Animals; D000831:Animals, Newborn; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D004624:Embryo Transfer / Q000662:veterinary; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods / Q000662:veterinary*; D008297:Male; D051379:Mice / Q000196:embryology*; D011247:Pregnancy