Effects of dietary androstenedione concentration on growth of tilapia fry (Oreochromis aureus Linnaeus)

Abstract

The effects of androstenedione on the growth, body composition, and survival of tilapia (Oreochromis aureus) fry were examined. Diets were supplemented by one of three androstene- dione concentrations (50, 100, or 200 mg/kg) for twelve weeks. The growth rate significantly increased in fish fed 50 mg androstenedione per kg compared to the control (p<0.01) but decreased dramatically at concentrations beyond 50 mg/kg. The specific growth rate, protein efficiency ratio, and food conversion ratio were significantly better in the 50 mg/kg group than in the other groups. Crude protein and survival at all androstenedione levels did not significantly differ from those of the control but lipid content dropped with 100 mg/kg supplementation.