不同血清种类及其浓度对牛卵母细胞体外受精的影响

以３个试验探索能否用自行采集、价廉的成年牛血清（发情母牛血清ＯＣＳ和阉公牛血清ＳＳ）来代替犊牛血清（ＦＣＳ）。试验１，比较ＯＣＳ和ＦＣＳ及其２种浓度（１０％和２０％）对牛卵母细胞体外成熟的影响。结果表明，ＯＣＳ影响牛卵母细胞体外成熟的效果与ＦＣＳ的效果无显著差异（均达到９０％以上）。同时，２种浓度间亦无显著差异。试验２，比较不同浓度的ＯＣＳ（０，１％，５％，１０％，２０％，５０％）对牛早期胚胎体外发育的影响。结果表明，早期胚胎的总囊胚率及７天龄囊胚率随着ＯＣＳ浓度从０到２０％的增加而提高。但当浓度增至５０％时囊胚率则有下降之趋势，然而与２０％浓度比较，差异不显著。试验３，探讨能否利用采集简单且价廉的ＳＳ来代替ＯＣＳ，进行了ＳＳ与ＯＣＳ在卵母细胞体外成熟及早期胚胎体外培养两阶段的效果比较。结果表明，ＳＳ亦完全可以替代ＯＣＳ。

IN VITRO FERTILIZATION AND CULTURE OF BOVINE OOCYTES TO BLASTOCYST STAGE IN MEDIA SUPPLEMENTED WITH DIFFERENT SOURCES AND CONCENTRATIONS OF SERA

Three experiments were conducted to investigate the effect of different sources and concentrations of sera on in vitro maturation (IVM),fertilization (IVF) and culture (IVC) to blastocyst stage of bovine oocytes. Experiment 1, oestrous cow serum (OCS) and fetal calf serum(FCS)at a level of either 10% or 20%, was compared to determine whether or not OCS could be instead of FCS in IVM of oocytes. The result revealed that OCS was the same effective as FCS at both levels of 10% and 20% in term of nuclear maturation. Experiment 2, different concentrations (0, 1%, 5%, 10%, 20% and 50%)of OCS were used to investigate an optimal concentration for IVC of early stage embryos.The result showed that rates of total blastocysts (BLs), day 7 BLs and hatched BLs increased as the concentration of OCS increased from 0 to 2 %, but these rates had a decreasing tendency when the concentration of OCS increased up to 50%. however,no difference was found between 50% and 20%. Experiment 3, a 2X 2 factorial experiment was conducted to determine whether or not steer serum (SS) could be instead of OCS in either IVM or IVC stage. No evidence was observed on difference between SS and OCS in rates of cleavage, BLs and hatched BLs in either IVM or IVC stage. This study suggests that SS can be instead of OCS and FCS in the IVF system of bovine oocytes, and these results will lead to a commercial use practically and economically.