Abstract: Combination of the IVM of mammalian oocytes and microstructure of real-time photographic technique makes the monitoring of the entire process of oocyte IVM possible. We observed morphological changes of bovine oocytes cultured in vitro using this technology and made preliminary analysis. The purpose of this study is monitoring oocyte maturation process in vitro, exploring and mastering the morphological variation pattern of bovine oocytes maturation process in vitro, so as to provide a reference for in-depth study of related fields. Bovine oocytes matured in vitro inside and outside CO₂ incubator, respectively. Base on confirming the impact of environment on the oocytes maturation, microscopic real-time camera system was used to monitor morphological changes of bovine oocytes maturation process in vitro and the rate of the first polar body emission in the process. The results showed that bovine oocyte maturation rate indicated no significant differences(P>0.05) under different environments such as inside or outside the CO₂ incubator. Through real-time monitoring oocyte maturation process, we found that part of oocyte cytoplasm would swell and restore subsequently in a short period of time, and then died eventually. The cause of this phenomenon was presumably associated with a called AQP3 water channel protein in oocytes.

Key words: bovine, oocytes, IVM, morphological observation, AQP3