奶牛四分胚分割研究

用玻璃针四等分7天的奶牛胚胎为四分(1/4)胚。同一胚胎2个四分胚装回空透明带内,另2个四分胚不装带,成对非手术移给受体奶牛。两次试验共分割胚胎(晚桑椹到囊胚期)11枚,得到42个四分胚。移植受体32头,有3头妊娠。最后,一头受体生出一对同卵双胎四分胚母犊,另一头产一四分胚母犊,均由装带四分胚发育而来。还有一头受体产一四分胚公犊,是由未装带的四分胚发育得到的。试验还分割一个8天囊胚,把一个无带四分胚先放在体外培养24小时再移入受体。结果获得一头四分胚母犊。

STUDY IN SIMPLIFIED QUARTERING OF BOVINE EMBRYOS

Day 7 dairy cow embryos were quartered directly with a glass needle resulting in the quarter embryos ( QEs ) . Two out of four QEs derived from one embryo were individually replaced into an empty zona pellucida ( ZP ) and the remaining both were not. They were trans -ferred nonsurgically in pairs ( with or without ZPs ) to synchronized recipients. Eleven embryos ( late morula to blastocyst stage ) in two experiments were split obtainig 42 QEs which were transferred to 22 recipients. Three recipients became pregnant. Finally, one gave birth with a set of female monozygotic QE twins, and the second produced a female calf. All of 3 calves derived from the QEs with the ZPs. The third recipient produced a male calf from a QE without ZP. Besides, a day 8 blastocyst was quartered and one QE without ZP was cultured in vitro for 24 h before transferring to a recipient which was delivered of a female calf later.