Copper during in vitro maturation of bovine oocytes: Role of cumulus cells.

ROSA DE; ANCHORDOQUY JP; ANCHORDOQUY JM; SIRINI MA; MATTIOLI GA; FURNUS C

Chascomus

Jornada; XVI Jornadas Anuales de la Sociedad Argentina de Biología; 2014

Sociendad Argentina de Biología

Our previous studies have demonstrated that copper (Cu) improves in vitro maturation (IVM) of bovine oocytes. Cumulus cells (CC) have an important role in the relationship between the oocyte and the microenvironment. The aim of this study was to investigate the role of CC during IVM in the presence of Cu. Cumulus oocyte-complexes (COC) were matured during 24 h with or without 0.6µg/mL Cu in three maturation systems: intact COC; denuded oocytes with cumulus cells monolayer (DO + CC);  and denuded oocytes (DO). Oocytes were fertilized in vitro and presumptive zygotes were in vitro cultured for 8 Days. Cleavage and blastocyst percentages were analyzes with a 2x3 factorial arrangement. There were no differences in cleavage rate between COC and DO+CC. The lowest cleavage rates were obtained in DO (p< 0.05). In addition, blastocyst rates were significantly higher in COC than in DO + CC and DO (p< 0.05). Independently of the presence of cumulus cells (COC, DO + CC or DO), the blastocyst rates were higher when 0.6 µg/ml Cu was added to IVM medium (p< 0.05). In conclusion, Cu increased the blastocyst rates regardless of the presence of CC during IVM.