Mastromonaco G F, Semple E, Robert C, Rho G J, Betts D H, King W A
Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
Reprod Domest Anim. 2004 Dec;39(6):462-7. doi: 10.1111/j.1439-0531.2004.00548.x.
Important differences exist between in vitro fertilized (IVF) and nuclear transfer (NT) bovine embryos. Studies have shown that although in vitro development is comparable, post-implantation survival is greatly reduced in NT embryos. In this study, we compare serum and bovine serum albumin (BSA) supplementation during oocyte maturation and embryo culture of IVF and NT embryos. In experiment 1, oocytes and embryos were randomly distributed into different treatment groups consisting of synthetic oviductal fluid (SOF) medium supplemented with either serum, fatty acid-free BSA (FAF) or fraction V BSA during maturation and/or culture to assess IVF embryo development. In experiment 2, oocytes were matured in SOF + serum or SOF + FAF and reconstructed embryos were cultured in SOF + FAF to assess NT embryo development. Among the IVF treatment groups, a greater number of blastocysts were observed in the steer serum (SER) group (IVM and IVC in SOF + serum) on day 6; however, no significant differences were seen in blastocyst development from day 8 onwards. Hatching frequencies on days 8 and 9 were significantly greater in groups with serum, with the exception of FAF (IVM and IVC in SOF + FAF) on day 9. For the NT treatment groups, the presence of serum during IVM resulted in a higher proportion of MII oocytes and increased blastocyst development and hatching rates were compared with supplementation of FAF. These results indicate that both serum and FAF provide comparable embryo development for IVF but not for NT bovine embryos.
体外受精（IVF）牛胚胎与核移植（NT）牛胚胎之间存在重要差异。研究表明，尽管体外发育情况相当，但NT胚胎植入后的存活率大幅降低。在本研究中，我们比较了IVF和NT胚胎在卵母细胞成熟及胚胎培养过程中血清和牛血清白蛋白（BSA）的添加情况。在实验1中，卵母细胞和胚胎被随机分配到不同处理组，这些处理组在成熟和/或培养过程中由添加血清、无脂肪酸BSA（FAF）或V组分BSA的合成输卵管液（SOF）培养基组成，以评估IVF胚胎发育。在实验2中，卵母细胞在SOF +血清或SOF + FAF中成熟，重构胚胎在SOF + FAF中培养，以评估NT胚胎发育。在IVF处理组中，在第6天，公牛血清（SER）组（SOF +血清中的IVM和IVC）观察到的囊胚数量更多；然而，从第8天起，囊胚发育情况未见显著差异。除第9天的FAF组（SOF + FAF中的IVM和IVC）外，血清组在第8天和第9天的孵化率显著更高。对于NT处理组，与添加FAF相比，IVM期间血清的存在导致MII卵母细胞比例更高，囊胚发育和孵化率增加。这些结果表明，血清和FAF对IVF牛胚胎的发育提供了相当的支持，但对NT牛胚胎则不然。
