开放式拉长细管冷冻法对牛卵母细胞体外受精后发育的影响

Effect of Open Pulled Straw Cryopreservation on Developmental Competence of Thawed Bovine Oocytes Following Maturation,Fertilization and Culture in vitro

在常规牛体外受精(IVF)技术的基础上,分别采用开放式拉长细管 (OPS,open pulled straw)法和细管法对未经成熟培养的卵丘卵母细胞(COCs)进行玻璃化冷冻,解冻后再进行体外成熟(IVM)、IVF和早期胚胎的体外培养(IVC)。结果表明,细管组和 OPS组的解冻后 COCs正常率分别为 59.4%±4.3%和 77.9%±4.1%(P<0 01);成熟率分别为48.2%±5.3%和66.0%±5.8%(P<0 01);卵裂率分别为18.5%±2.0%和32.8%±1.4%(P<0 01);8 细胞阶段的成功率分别为14.8%±2.5%和 24.8%±1.5%(P<0 01);桑椹胚发育率分别为 0 和5 3%±1.1%,明显低于未经冷冻的鲜卵组(21.0%±3.8%;P<0 01);囊胚发育率分别为0和4.0%,明显低于鲜卵组(P<0 01)。说明OPS玻璃化冷冻法可以使未经成熟培养的牛 COCs冷冻后获得桑椹胚和囊胚,但桑囊胚发育率仍较低,方法有待改进。

Experiments were conducted to study the effect of different vitrifications, straw and open pulled straw(OPS ), on survival, in vitro maturation, in vitro fertilization, and post-fertilization development of vitrified-thawed immature bovine COCs(cumulus oocyte complex).The results as follows: The recovery of post-thaw morphologically normal COCs in straw and OPS were 59.4%±4.3% and 77.9%±4.1% respectively(P<0.01);The maturation rates were 48.2%±5.3% and 66.0%±5.8% respectively(P<0.01);The cleavage rates were18.5%±2.0% and 32.8%±1.4% respectively(P<0.01);The percentage of 8-cell embryo were 14.8%±2.5% and 24.8%±1.5% respectively(P<0.01);The percentages of morula in straw , OPS and fresh oocytes were 0, 5.3%±1.1%and 21.0%±3.8% respectively(P<0.01);The percentage of blastocyst in straw , OPS and fresh oocytes were 0, 4.0%±1.0%and 17.1%±2.7% respectively (P<0.01).In conclusion,the vitrified-thawed immature bovine COCs by OPS could develope to morula and blastocyst stages after IVF,although it was low.