• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.53-53
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• 2003

The aim of this study was to determine the interactive effects of BSA and EGF on the viability and development of porcine diploid parthenotes developing in vitro. The addition of 0.1 and 0.4% BSA to the culture medium enhanced the development of 4-cell parthenotes to the blastocyst stage but EGF had no effect. However, while BSA also increased cell numbers, it did so only when EGF was also present. Either agent on its own had no effect. Similarly, apoptosis in the blastocysts was not influenced by either agent on its own but was reduced when both BSA and EGF were present. Furthermore, semi-quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) revealed that EGF enhanced the mRNA expression of BclxL in the presence of 0.4% BSA but BSA and EGF alone had no effect. EGF and/or BSA did not influence Bak gene expression in the blastocyst stage parthenotes. These results suggest that BSA has both beneficial and detrimental effects on the viability of porcine diploid parthenotes developing in vitro and that exogenous EGF may block some of the detrimental effects of BSA, possibly by inhibiting the BSA-induced apoptosis by increasing Bcl-xL expression. This results in a net increase in cell numbers in porcine diploid parthenotes developing in vitro.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.718-724
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• 2007

Considerable attention has been focused on the cloning of mammalian embryos, as a consequence of poor development, in order to enhance the application of genetic engineering. Experiments were conducted to compare the developmental competence of parthenotes and reconstructed (NT) rabbit eggs with fetal fibroblasts (FFs) following various activation regimens. Oocytes and NT eggs were exposed to: electric stimulation (EST, Group 1) and EST followed by 6-dimethylaminopurine (DMAP, Group 2), cycloheximide (CHX, Group 3) or DMAP/CHX (Group 4). Pronuclear (PN) status, cleavage, blastocyst development and the ploidy were assessed. In parthenote groups 1, 2, 3 and 4, the PN formation differed significantly. And, the cleavage and blastocyst rates were 41.7 and 5%, 75.6 and 53.7%, 68 and 36%, 82.1 and 52.6%, respectively, among treatments. Polyploidy was observed in 17.2% of EST plus DMAP and 44.9% of EST plus DMAP/CHX groups. In SCNT groups (Group 1, 2, 3 and 4), the cleavage and blastocyst rates were 28.6 and 7.1%, 58.3 and 29.2%, 56.8 and 24.1%, 64.5 and 27.8%, respectively. The chromosomal composition differed significantly (p<0.05) among treatments. In Group 2 and 3, 53.8% and 81.8% of embryos revealed diploid chromosomal sets, respectively. However, in Group 4, 53.3% of embryos showed abnormal ploidy (mixoploid). Although DMAP or combination with DMAP/CHX resulted in higher in vitro development of rabbit SCNT embryos, higher incidence of chromosomal abnormality may induce problems related to fetal loss of at late stage of development.