乳牛胚胎冷冻保存技术和受胎率的研究

The Techniques of Embryo Cryopreservation and Pregnancy in cow

51枚可用胚胎,依次通过含有3.3%,6.7%,10%甘油的抗冻剂处理后,装入26支塑料细管,置于冷冻仪上,以每分钟降低1℃的速率从室温降-6.5℃,平衡5 min 后进行诱发植冰,又平衡5 min,再以每分钟降低0.3℃的速率降至-36℃,平衡10 min 后直接投入-196℃的液氮中保存。先后从液氮中取出16支冷冻保存不同时间(1,8,9,10,28,29,31,32,62天)的冷冻胚胎塑料细管,用30℃温水进行快速解冻,分3步脱除甘油,回收32枚胚胎,其中可用胚胎22枚分别移植给11头受体牛,结果4头妊娠(妊娠率为36.3%)并顺利生下4头发育正常的犊牛。

Fifty one embryos were treated in 3 steps with cryoprotective agents containing 33.3%,6.7%,10%glycerin respectively,then put into 26 plastic straws.With freezing apparatus,from room temperature to-6.5℃ at the rate of 1℃ per minute,then kept stabble for 5 minutes and gone a step further to lower the tempereture to -36℃ at the rate of 0.3℃ per minute.After staying 10 minutes,embryos were put into liquid nitrogen and stored at -196℃.The 32 frogen embryos with different cryopreservation days(1,8,9, 10,28,29,31,32,62)in 16 plastic straws were fast thawed in 30℃water bath.In order to get rid of the cryoprotective agent glycerin,3 steps method was adopted.Finally,32 embryos were obtained and 22 transferable embryos were selected from them.These embryos were thentransfered to 11 recipients.As a result,4 recipients got pregnancy(36.3%)and 4 healthy calves were born at fullterm.