Effects of different maturation periods on in vitro maturation of bovine oocytes

Abstract

Primer oocytes (n=157) collected from ovaries of slaughtered cows were matured at 39 degrees C with 95-100% humidity and under a gas mixture of 5% O-2 5% CO2 and 90% N-2 for 22 (n=52), 24 (n=52) and 26 (n=53) hours. Modified Parker's Medium (MPM) supplemented with FSH and 20% ECS was used as maturation medium. At the end of these periods all oocytes were fixated in ethanol:acetic acid in the ratio of 3:1 for 2A hours and stained by %2 aceto-orcein to evaluate the maturational criteria.