Studies On Goat Embryo Bisection

This experiment carried on a systematic study on each link and its influence factors of goat embryos bisection technology.Part One Superovulate the donors and collect the embryo in 5.5-6.5 days after insemination. The usable embryo were divided into 4 experiment groups: yeanling morulae, yeanling multiparity blastocyst, sheep morulae and multiparity sheep blastocyst. The bisection was performed in 0. 2M sucrose PBS and in PBS respectively with micromanipulation. Followed by in vitro culture, the rates of demi-embryos development to blastocysts and the cell number of blastocysts were registered. The results indicated that: the usable embryo rates of yeanling group were higher than multiparity sheep group (88. 9%vs73. 8%, P>0. 05) ; the usable demi-embryos rates and the cell number of blastocysts of 4 groups were similar (P >0. 05) ;the demi-embryos development rates of yeanling group(including morulae , blastocyst) were higher than multiparity sheep group (68. 8%vs68. 2%x 85. 7%vs81. 8%, P>0.05) .Part Two 1. Superovulate the donors and collect the embryo in 5. 5-6. 5 days after insemination, dispose acceptors oestrus the same term .2. A portion of morulae and blastocyst were bisected in 0. 2M sucrose PBS and in PBS respectively with micromanipulation. Followed by in vitro culture, the rates of demi-embryos development to blastocysts and the cell number of blastocysts were registered.The results indicated that: The blastocyst rates of demi-embryos in 0. 2molS+ PBS group(including morulae , blastocyst) were higher than PBS group(68. 2%vs58.3% x 81. 8%vs80. 0%, P>0. 05) ; the usable demi-embryos rates and the cell number of blastocysts were higher than PBS group too (P>0. 05) . 3. Morulae and blastocyst were bisected in 0.2M sucrose PBS with 3 means (micromanipulation machine assistant, manual bisection). A portion of usable demi-embryos were cultured in vitro 18 hr; the rates ofdemi-embryos development to blastocysts and the cell number of blastocysts were registered. The other portion of demi-embryos were transferred surgically into recipients. The results indicated that: when bisecting morulae in 0.2M sucrose PBS, the blastocyst rates of demi-embryos of micromanipulation gruop were higher than manual bisection group(68. 2%vs22. 2%, P<0.05), micromanipulation group and machine assistant group were similar (P>0.05) ; the pregnancy rates of micromanipulation group and machine assistant group were higher than manual bisection group (33. 3%, 33. 3%vs0% , P >0.05). When bisecting blastocyst, the blastocyst rates of demi-embryos of 3 gruops were similar(P>0.05); the pregnancy rates of machine assistant group were higher than micromanipulation group and manual bisection group(66. 7%vs 33.3%, 33.3%, p>0.05). The usable demi-embryos rates and the cell number of blastocysts of 6 experiment groups were similar (P>0. 05) .4. In 0.2M sucrose PBS morulae and blastocyst were quartered directly resulting in the quarter embryos (QEs) with concatenation or disconnected bisection. QEs were cultured in vitro 18 hr, the rates of QEs development to blastocysts and the cell number of blastocysts were registered.The results indicated that: when disconnected bisecting blastocyst, the usable QEs rates were higher than the other 3 experiment groups (87.5%vs50. 0%, P<0.05; 87. 5%vs 62. 5%, P>0.05; 87. 5%vs 71. 4% P >0. 05), the rates of QEs development to blastocysts were were higher than the other 3 experiment groups too(71. 4%vs50.0% 53. 3%, 55.0% , P >0. 05).Conclusion: 1. Yeanling sheep can be as donors in embryo bisection, the usable demi-embryos rates and the blastocyst rates of demi-embryos were higher than multiparity sheep group (P>0.05) .2. Under farm condition, bisecting morulae and blastocyst adapt to in 0. 2M sucrose PBS; bisecting morulae adapt to with machine assistant bisection, bisecting blastocyst adapt to with manual bisection; quartering directly embryointo QEs had better choice blastocyst , and adapt to with machine assistant bisection disconnected.