摘要
为了探讨蛋白质添加剂对牛卵母细胞体外成熟、体外受精及早期胚胎体外培养的影响，通过２３３８个卵母细胞，按２×２×２设计方法进行试验，即在体外成熟、体外受精及早期胚胎体外培养三个阶段的培养液中，添加与不添加蛋白质物质（体外成熟与体外培养为发情母牛血清，体外受精为牛血清白蛋白）。试验结果表明，在体外成熟阶段的培养液中，有无发情牛血清对牛卵母细胞的核成熟无显著影响（有血清组为８９％，无血清组为９０％）。但在体外受精阶段，受精液中含有牛血清蛋白质处理组的卵母细胞受精后，分裂率显著地高于无血清蛋白质组（Ｐ＜０．０１，８４％ｖｓ７２％）。同样，在早期胚胎体外培养阶段，含有发情牛血清的培养液大大促进早期胚胎的发育，与无血清组比较，其差异性极显著（Ｐ＜０．０１，３５％ｖｓ２１％）。同时，含血清组的胚胎孵化率亦显著地高于无血清组（Ｐ＜０．０１，６９％ｖｓ４７％）。本研究表明，蛋白质添加剂在ＩＶＦ和ＩＶＣ阶段是必需的，而在ＩＶＭ阶段则不甚重要。
A 2X2X2 factorial experiment was designed to determine the effect of protein supplements on in vitro maturation (IVM), fertilization (IVF) and culture (IVC) to blastocyst and hatched stage of bovine oocytes in the present study.A total of 2 338 oocytes with eight replicates, aspirated from follicles of 2￣8 mm in diameter of ovaries obtained at a local abattoir, was randomly allocated to one or other of eight treatment groups (two factors: with or without protein supplements-oestrous cow serum (OCS) in IVM and IVC and bovine serum albumin (BSA) in IVF, cross each stage of IVM, IVF and IVC). IVM and IVF were carried out with the same procedures as previously described by Lu et al (1987, Vet. Rec. 121, 259). A sample of oocytes in IVM stage was examined for nuclear maturation (metaphase Ⅱ). Cleavage as an endpoint of fertilization was evaluated at 44￣48 h after insemination. For IVC, the cleaved eggs (2￣8 cells) were co-cultured with granulosa cell monolayers in the same medium and condition as IVM for 5￣7 days forblastocyst (BL) development and for 2￣3 more days for hatched BL stage.The pooled data from the 2X2X2 factorial experiment showed that there was no significant difference (P>0. 05) in nuclear maturation between the presence (89%) and absence (90%) of OCS in IVM medium. However, significant difference (P<0. 01) was found between the presence and absence of protein in rates of cleavage (84% vs 72% ), BL (35% vs 21 % ) and hatched BL (69% vs 47% ). Normal BL development and hatched BL were obtained when the protein supplement was present in IVC medium regardless of protein presence or not in IVM or IVF medium. In conclusion, protein supplement is necessary for IVF and IVC of bovine oocytes but not for IVM.
关键词
蛋白质
牛
卵母细胞
体外成熟
rotein additives
bovine oocytes
in vitro maturation
in vitro fertilization
early embryo
in vitro development
