Effect of Macroscopic Classification of Bovine Ovarian Follicles on Steroidogenic Activities of Granulosa Cells in Vitro

Abstract

This study aimed to investigate relationships between steroidogenic characteristics and abilities, and some macroscopic characteristics of bovine ovarian follicles and to relate this criterion to the physiological status of the follicles. Follicular fluid of 5 to 8 mm diameter follicles from bovine ovaries (n=46) were analysed and steroidogenic activities of granulosa cells were studied. For the macroscopic classification of the follicles (n=232), appearence of the follicles, thecal vascularization, the colour of theca interna and the presence of follicular debri were determined. Follicles were classified as non-atretic, intermediate and atretic using the criterion above. Oestradiol-17β concenration was higher than progesterone concentration in the follicular fluid of non-atretic follicles (P<0.01). Oestradiol-17β and progesterone concentrations in the follicular fluid were 034 pg oestradiol/ml and 82.4 ng progesterone/ml for non-atretic follicles, 442 pg oestradiol/ml and 274.6 ng progesterone/ml for intermediate follicles, and 113 pg oestradiol/ml and 769.5 ng progesterone/ml for atretic follicles, respectively. Granulosa cells from non-atretic, intermediate and atretic follicles produced 402, 106 and 62 pg oestradiol-17β/105 cells, respectively, during the incubation period (P<0.01). While granulosa cells from non-atretic follicles produced 76.2 ng progesterone/105 cells, granulosa cells from intermediate and atretic follicles secreted 130.8 and 1412.3 ng progesterone/105 cells, respectively, into the incubation medium. In conclusion, therere differences between steroidogenic characteristics and abilities of follicles macroscopically classified as non-atretic, intermediate and atretic, and macroscopic evaluation of follicles may be used for reflection of physiological status of follicles.