Study On Change Of Ca～(2+)of Goat Oocyte During Maturation In Vitro

Intracytoplasmic free-Ca2+ of goat oocytes at different developmental stages was measured to investigate the effect of Ca2+on oocyte maturation by calcium fluorescent probe Fura-2/AM.Effects of hormone, collecting methods, reproductive season, water quality and culture period on the IVM of goat follicular oocytes were studied. The results showed that after culture of 22-24h in medium including 1.5 μg/ml 17 β -E2, 20 μg/ml LH, 10 μg/ml FSH (LH:FSH=2:1), oocytes maturation rate was higher than the other groups; the oocyte maturation rate of goat in reproductive season was higher than that of non-reproductive season; but collecting methods and water quality have no significant effects on the IVM of goat oocytes.Follicular oocytes had developed to the stage of GV, GVBD, M I, MII after 0 h, 4 h, 14 h and 24 h of culture, respectively, judged by morphological cretirea of oocyte chromosome stained with orcein. And we measured intracytoplasmic free-Ca2+ during the in vitro maturation of follicular oocytes. The average Ca2+ concentration at the stage of GV, GVBD, MI and MII were 78.06, 147.41, 126.97, 97.73 nmol/L, respectively. However, the oocytes cultured in the medium without calcium were not able to appear GVBD. Therefore, the occurrence of GVBD and the physiological process from the stage of GVBD to M I are Ca2+ dependent.