Abstract

This study was aimed at determining the effect of cysteine supplement during in vitro maturation of bovine oocytes. Cumulus-oocyte complexes (COCs) from abattoir ovaries were matured in vitro in Hepes-TCM 199 supplemented with 0.2 mM sodium pyruvate, 1 µg/ml 17-β-estradiol, 10% fetal calf serum (FCS), 0.5 µg/ml bFSH and 0 (control) and 100 or 500 µM/ml of cysteine for 24 h. When COCs matured in TCM 199 media with 500 µM/ml cysteine, the rate of maturation were increased as compared to the control group (53.33 vs. 33.33%, respectively) (P<0.05). Also, the percentage of degenerated oocytes in the treatment groups was lower than that in the control group (P<0.05).

Key words: Bovine, cysteine, in vitro maturation (IVM), oocyte.