Document Type : Short communication
Department of Fisheries and Environmental Sciences, Faculty of Natural Resources, University of Tehran, Karaj, Iran
Department of Fisheries, Faculty of Marine Sciences, Chabahar Maritime University, Chabahar, Iran
Department of Biodiversity and Ecosystem Management, Environmental Sciences Research Institute, Shahid Beheshti University, G.C., Tehran, Iran
International Sturgeon Research Institute, Rasht, Iran
In the present study, the steroids [Cortisol (C), testosterone (T), 11-ketotestosterone (11-KT), progesterone (P), 17,20ß,21-trihydroxy-4-pregnen-3-one (20βS), 17α,20β dihydroxy-4-pregnen-3-one (DHP) and 17α, hydroxyprogesterone (OHP)] in both blood serum (BS) and ovarian fluid (OF) as well as the rate of Germinal Vesicle Breakdown (GVBD) were measured for the Persian sturgeon, Acipenser persicus. The high positive correlations were found between 20ßS and P levels in both OF and BS. Additionally, 20ßS and P exhibited the positive correlation with percentage of GVBD while a significant negative correlation was found between Polarization Index (PI) values and percentage of GVBD. The levels of 20ßS and P in both BS and OF were significantly higher in females with high GVBD rate than in females with the lowest GVBD rate. Therefore, the percentage of GVBD may be affected by 20ßS and P levels in both OF and BS as well as by developmental stage of oocytes.