Effect of Cysteamine Supplementation on in vitro Maturation of bovine Oocyte

This study was aimed at determining the effect of cysteamine supplement during in vitro maturation of bovine oocytes. Cumulus-oocyte complexes (COCs) from abattoir ovaries were were obtained from local abattoir (Tabriz abattoir, East Azarbaijan, Iran) shortly after slaughter and transported to the laboratory in 0.9% NaCl solution plus 100 IU/ml potassium penicillin G, and 100 μg/ml streptomycin sulfate at 30-35°C, within 2 to 4 h from slaughter. 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 0.1, 0.5 or 1 mM/ml of cysteamine for 24 h. When COCs matured in TCM 199 media with 0.1 mM/ml cysteamine, the rate of maturation were increased as compared with control group (46.66 vs 33.33%, respectively). The maturation rate of oocytes in media with 0.5 mM/ml cysteamine (56.55%) was significantly higher than control group (33.33%) (P