Submitted to: Cloning and Stem Cells
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/12/2003
Publication Date: 4/20/2003
Citation: Zhu, J., King, T., Dobrinsky, J.R., Harkness, L., Ferrier, T., Bosma, W., Schreier, L.L., Guthrie, H.D., Desousa, P., Wilmut, I. 2003. In vitro and in vivo developmental competence of ovulated and in vitro matured porcine oocytes activated by electrical activation. Cloning and Stem Cells. Volume 5(4):355-65. Interpretive Summary: The objective of this study was to evaluate the development of embryos produced by electrical activation (parthenotes) compared to control embryos from mated female swine. Early embryo growth to the blastocyst stage for control embryos and parthenotes did not differ in culture. Both control embryos and parthenotes were able to develop for 30 days, although the parthenotes were significantly smaller than control embryos. Development of parthenotes terminated around 31 days post-estrus after transfer into recipient female pigs. These data are important to scientists because the results reveal the extent of parthenogenetic development in swine and show that pig parthenotes may be useful to provide a supportive role in the establishment of a pregnancy when transferred along with limited numbers of fertilized or cloned pig embryos.
Technical Abstract: The objective of this study was to evaluate the in vitro and in vivo developmental competence of parthenogenetic (parthenote) pig embryos derived from ovulated and in vitro matured (IVM) oocytes. A total of four experiments were carried out. These demonstrated that the mean blastocyst rates from stimulated ovulated and IVM pig oocytes were not significantly different (61% vs. 46%, p>0.05) follwing in vitro culture. Both ovulated and IVM pig parthenotes were able to develop in vivo for 30 days. Parthenote fetuses collected 21 and 30 days post estrus were morphologically normal but significantly smaller and lighter than fertilized controls (p<0.01). IVM pig parthenotes stopped developmental around 31 days post estrus.