Effect of follicular fluid and floating drop culture system on the maturation of bovine oocytes

Abstract

The quality of mature oocyte plays a vital role in in vitro fertilization, ICSI or cloning. Therefore, the aim of this study was to establish an optimal in vitro maturation (IVM) system for bovine oocytes. In the first experiment, the effects of the cumulus-granulosa cells complexes (OCGs) collected from ovaries of bovine from three different slaughter houses in the south of Vietnam – Ho Chi Minh City (Vissan), Di An Town (Ut Hao), Long An province (Thanh Vinh) on in vitro maturation rate were examined. In the second experiment, the IVM medium supplemented with four different concentrations of bovine follicle fluid (BFF), 5%, 10%, 15% and 20%, was investigated. Besides, two culture methods using floating drop covered with paraffin oil or 48-wells cultured dish were performed. With the results from the first experiment, oocytes collection from different slaughter houses in the South of Vietnam, Ho Chi Minh City (Vissan), Di An Town (Ut Hao), Long An (Thanh Vinh), did not affect to the oocyte maturation rate. Results from the second experiment suggested that maturation culture medium supplemented with 15% BFF and cultured in floating drop covered with paraffin oil obtained the highest rate of oocytes reached metaphase II (60.33%). In conclusion, the optimal IVM system for bovine oocytes was established consisting of floating drop containing IVM medium supplemented with 15% BFF covered with paraffin oil.