Effect of Hormones on Growth and Food Utilization of the Indian Major Carp, Cirrhinus mrigala

Abstract

The influence of human chorionic gonadotropin (HCG) and testosterone propionate (TP) at the dosages of 10 ppm and 3 ppm respectively, and their combination (HCG+TP) of 8 ppm and 1.5 ppm on the growth, food conversion, digestibility, enzyme activity, nucleic acid content. Oxygen consumption and ammonia excretion of the Indian Major Carp, Cirrhinus mrigala was assessed. The experiments were conducted in cement tanks (5x4x1 m) for 98 days by feeding hormones through fish meal based prepared diet having 35% protein. Growth of C. mrigala was high in hormone fed fishes than the control with the maximum growth recorded in the HCG treatment followed by HCG+TP, TP and control. Specific growth rate (SGR), food conversion efficiency (FCE), apparent protein and lipid digestibility were high in hormone fed fishes (p < 0.01) than the control. The enzyme activity in the foregut, midgut and hindgut showed marked variation with the highest activity noticed in the foregut followed by midgut and hindgut. The rates of oxygen consumption and ammonia excretion of hormone fed fishes were found to be not significantly different from control (P > 0.05). The hormones stimulate growth through increasing the appetite and enhancing food utilization and protein synthesis.