Maturation of sheep oocytes with antioxidant α-tocopherol which are activated by parthenogenesis

Abstract

This study was conducted to investigate the competence of sheep oocytes which are matured with antioxidant α-tocopherol by parthenogenesis activation. Oocytes from slaughterhouse were matured in tissue culture medium (TCM)-199 supplemented with 10% fetal bovine serum (FBS), 10 IU/ml pregnant mare serum gonadotrophin (PMSG), 10 IU/ml human chorionic gonadotrophin (hCG), 1 µg/ml estradiol, 50 µg/ml gentamycin, and with or without 150 µM α-tocopherol supplementation, then were parthenogenetically activated by exposing to 5 µM calcium ionophore for 5 min, and in medium containing 5 µg/ml cytochalasin B for 4 h. Furthermore oocytes were cultured in TCM 199 + 10% FBS either with or without supplementation of 150 µM α-tocopherol. Result of this experiment revealed that the percentages of activated oocytes with supplementation of 150 µM α-tocopherol only in maturation medium (63.41%) significantly higher (P<0.01) than the control group (50.00%) and the supplemented only in culture medium (51.02%). Furthermore, no significantly difference (P>0.05) in the number of oocytes with 1 pronucleus (PN), 2 PN, and more than 2 PN. It is concluded that the supplementation of 150 µM α-tocopherol on the maturation medium could also increase the percentage of activated oocytes optimally.