OVARIAN-STEROID LEVELS IN SALAMANDRA-SALAMANDRA INFRAIMMACULATA DURING THE REPRODUCTIVE-CYCLE

Gonadal steroid levels were determined in the ovary of Salamandra sala mandra infraimmaculata during the reproductive cycle in populations fr om a xeric region in northern Israel. Varying proportions of previtell ogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of matur e oocytes were greater between December and April, after parturition. The levels of 17 beta-estradiol and testosterone rose during oocyte vi tellogenesis and maturation. Levels of progesterone and 17 alpha-hydro xy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females. (C) 1997 Academic Press.