Physiological Studies on Growth-promoting Effect of Protein-anabolic Steroids on Fish-II

Effects of 4-Chlorotestosterone acetate on Rainbow trout

Abstract

In this study the authors administered 4-Cl to the trout for promoting the growth.
The optimum dose of 4-Cl for the trout was 2.5mg per fish in sexually active or inactive season. The growth-promoting potency of 4-Cl seems to be due mainly to an increase in utility of food given. The administration of doses higher than 2.5mg produced the pycnosis of interrenal and liver cells, and did not bring about the growth-promoting potency on the trout.
The suppressive action to gonadal maturation and hepatotrophic action were both observed as secondary actions of 4-Cl. As in the case of goldfish, 4-Cl suppressed a deposition of yolk in the oocytes and farther development beyond the stage of spermatogonia in testes. The suppression seems to be caused by blocking the release of gonadotrophins in the meso-adenohypophysis. On the other hand, the hypertrophy of liver was found to be due to hypertrophy of liver cells which stored a great amounts of glycogen. Further, the relation between the deposition of glycogen in the liver and the gluconeogenesis of interrenal cells was discussed.