Morphologic comparison of ovulated and in vitro-matured porcine oocytes, with particular reference to polyspermy after in vitro fertilization

In vitro Fertilization and Development of Pig Oocytes Inseminated with Boar Sperm by Different Sperm Washing Media after Thawing of the Frozen Straws

“…In this study, we found out extremely low incidence of polyspermic penetration. These results were consistent with the above reports of Martinez et al (1996), Wang et al (1998Wang et al ( , 1999 and Funahashi and Nagai (2001).…”

Pig oocytes with a large perivitelline space matured in vitro show greater developmental competence after parthenogenesis and somatic cell nuclear transfer

“…This result indicates that cytoplasmic maturation might be improved in oocytes with a wide PVS, which was supported by our observation of increased intracellular GSH level and mRNA transcript abundance after IVM. Our results are consistent with previous results demonstrating that ovulated pig oocytes had a wider PVS and showed decreased polyspermic fertilization than IVM oocytes (Wang et al, ) and that human oocytes with a larger‐than‐normal PVS were associated with a 1.8‐fold higher probability of resulting in good‐quality embryos (Ten et al, ). In contrast, Xia () demonstrated a negative effect of fragmented first polar bodies, a large PVS, and cytoplasmic inclusions in human oocytes on the percentage of zygotes and embryo quality.…”

“…Oocytes with a larger PVS, however, showed higher developmental competence than oocytes with a smaller PVS. In this study, the average PVS size of oocytes matured in M‐199 was 2.9 µm, which was similar to the previously reported PVS size of oocytes (3.1 µm) matured in vitro in NCSU‐23 medium with hormones and 10% porcine follicular fluid (Wang et al, ), while the average PVS size of ovulated pig oocytes was 12.4 µm, which was approximately three times wider than that of IVM oocytes. This result indicates that cytoplasmic maturation might be improved in oocytes with a wide PVS, which was supported by our observation of increased intracellular GSH level and mRNA transcript abundance after IVM.…”

Amount of Hyaluronan Produced by Mouse Oocytes and Role of Hyaluronan in Enlargement of the Perivitelline Space

“…Recently, it has been suggested that there could be a relationship between the size of the perivitelline space and the incidence of polyspermy in porcine and mouse oocytes [1][2][3][4]. In the present investigation, it was confirmed that the size of the perivitelline space in mouse DOs treated with MU was smaller and that the incidence of polyspermy in those after insemination was higher than those in the control DOs.…”