The effects of steroids on final maturation and ovulation of oocytes from brook trout (Salvelinus fontinalis) and yellow perch (Perca flavescens).

Abstract

The effects of various steroids on germinal vesicle breakdown (GVBD) and ovulation were investigated in yellow perch (Perca flavescens) and brook trout (Salvelinusfontinalis) oocytes using an in vitro incubation technique. Both progestogens and 1 1-deoxycorticosteroids induced GVBD in brook trout. Progestogens and 11-deoxycorticosteroids also induced GVBD in yellow perch oocytes, however, at higher concentrations they induced a significant percentage of ovulation with or without germinal maturation. At lower concentrations only 20P-dihydroprogesterone continued to induce ovulation while only 1 1-deoxycortisol was very effective in inducing GVBD. In both yellow perch and brook trout, 11-oxygenated corticosteroids or androgens were relatively ineffective in inducing either GVBD or ovulation.