Pubertal effects of 17α-methyltestosterone on GH-IGF-related genes of the hypothalamic-pituitary-liver-gonadal axis and other biological parameters in male, female and sex-reversed Nile tilapia.

The influence of 17α-methyltestosterone (MT) on growth responses, biological parameters and the expression of genes involved in the GH-IGF pathway of the hypothalamic-pituitary-liver-gonadal axis were investigated in female, male, and sex-reversed Nile tilapia to evaluate the relationship between sex and MT-induced changes in these parameters. Female fish had a lower growth rate than male and sex-reversed fish, and MT increased growth performance and duodenal villi in females. Most but not all biological parameters of sex-reversed fish were similar to those of male fish.