Effect of GPAG Supplement on Porcine Oocyte Maturation and Its Following Embryonic Development by Parthenogenetic Activated

The aim of this study was to compare the effect of GPAG and commonly used FCS on porcine oocyte maturation and subsequent embryonic development after the fertilization.COCs were aspirated from follicles and cultured for 16, 24, 32, 40 and 48 h in TCM-199 medium either with GPAG or FCS.After 24 h with GPAG,89.4% of oocytes reached M 1 stage while in the medium supplemented with FCS,only 27.7% of oocytes reached the same stage (P＜0.05).Prolonged incubation for up to 32 h clearly demonstrated that some of oocytes cultured in GPAG medium were at M Ⅱ stage (35.7%),few of oocytes from FCS medium were at M II stage (7.5%) (P＜0.05).Both groups of oocytes reached the same stage of maturation within 48 h. After 48 h of culture,the oocytes with extruded polar bodies were inseminated.Fertilized oocytes were cultured in PZM3 medium supplemented with 3 mg·mL-1 of BSA. After 7 days,the development and the quality of embryos were evaluated.The results showed that the maturation of oocytes in the presence of GPAG significantly increased their subsequent developmental ability when compared with FCS supplementation (29.2%:18.9% of blastocysts,P＜0.05).However,differential staining revealed that once blastocysts were formed in either group, they had the same total cell number (39:38) and the ICM/total cell ratio (0.26:0.28).