Dietary Incorporation of Ractopamine Hydrochloride Improves Body Composition and Metabolic Enzyme Activity in Calbasu, Labeo calbasu Fingerlings, despite High- and Low-Protein-Supplemented Diet

A 60-day feeding trial was conducted to examine the effect and interaction of dietary ractopamine hydrochloride (Rac) supplementation in diets with varied levels of protein and lipid for L. calbasu fingerlings. To attain this, the fish body compositions, digestive and metabolic enzyme activity were assessed. In total, nine diets were fed in triplicates to four hundred and five healthy Calbasu, Labeo calbasu fingerlings, based on ractopamine supplementation, viz., control (0 mg/kg), T1 (10 mg/kg), and T2 (20 mg/kg). The diets were further assigned in different levels of protein and lipid, viz., 35% protein and 6% lipid, 30% protein and 9% lipid, and 25% protein and 12% lipid. At the end of the trial, it has been observed that the inclusion of ractopamine hydrochloride at 20 mg/kg-1 of basal diet significantly (p