| dc.description.abstract | Growing porcine oocytes are tough challenge for scientists in order to culture them in in vitro system since the capacity of these oocytes reached to full meiotic competence are not high as the fully grown oocytes from lagre antral follicles (4-6mm in diameter). Hence, this study aims to establish the standard in vitro-growth (IVG) culture system of oocytes from pig preantral follicles and investigate the proliferation of surrounding cells and chromatin configuration of these oocytes after culturing. In order to do that, growing oocytes from preantral follicles 1.5mm and 2mm in diameter were cultured for 3 days in the medium supplemented with 0.05IU/mL FSH, 0.5mM dbcAMP, and 10-4 mol/L estradiol 17β. Then, oocytes were subsequent to in vitro maturation (IVM) for 42hrs including of bicarbonate-buffered TCM 199 with the supplement of 10% porcine follicle fluid and 0.1IU/mL human chronic gonadotrophin (hCG). The results illustrated that after IVG, growing oocytes showed significant increase of the number of surrounding cell layers. Moreover, the growing oocytes after IVG were able to gain successful fully grown stage (Germinal vesicle I stage) compared to those without culturing IVG (62.8%; 63.8% and 0%-11.1% respectively). After in vitro maturation, most of these oocytes could progress the meiotic competence reaching to Germinal vesicle breakdown stages (GVBD), which shown similar levels to the fully grown oocytes from 4-6mm antral follicles (57.8%; 51.2% and 63% respectively). However, only 2mm preantral follicles could reach to metaphase II with a low rate (7.3%). Therefore, this research is strongly claimed that FSH, dbcAMP and Estradiol 17β supported the growth of oocytes reaching to fully grown stages and increased the rates of oocytes undergo germinal vesicle breakdown stages.
Keywords: preantral follicles, growing oocytes, in vitro growth (IVG), in vitro maturation (IVM) | en_US |
