Effects of genistein on gamete quality, steroidogenesis and serum biochemicals in goldfish (Carassius auratus)

The objective of the present investigation was to determine the effects of genistein and 17β-estradiol (E2) on reproductive physiology in female goldfish (Carassius auratus) during pre-spawning phase. Female goldfish received intraperitoneal injections of E2 (10 μg/g body weight), one of two genistein doses (5 μg/g body weight, G5, or 50 μg/g body weight, G50), or the injection vehicle (CTRL) every other day for 10 days prior to spawning. Disruptions in reproductive capacity were determined by measuring indices of oocyte quality, serum metabolites and sex steroids. Genistein reduced GSI but did not affect on fecundity and oocyte diameter. E2 and genistein (G5 and G50) reduced plasma T, while plasma E2 significantly increased at G50 and E2 treatment groups in comparison to the G5 and the control groups. Plasma biochemical indexes (phosphorus, cholesterol and triglyceride) were significantly elevated by genistein (G50) and E2 treatment. These findings suggesting that high dietary genistein may impair endocrine system of fishes and finally impair their reproductive performance.