ABSTRACT An experiment was conducted during 60 days with forty pacu males fed diets supplemented with increasing concentrations of ractopamine (0.00, 11.25, 22.50, 33.75, and 45.00 mg kg−1). Eight fish were evaluated for each experimental diet. Performance and survival rate of the fish were measured. At the end of the experiment, blood was collected to determine the levels of cortisol, triacylglycerol, and protein. Moreover, the liver was collected to determine the activities of glucose-6-phosphate dehydrogenase and malic enzymes. The fillets were collected to determine chemical composition, and histologic cuts were analyzed to verify muscle growth and deposition of adipose tissue between muscle fibers. Increasing concentrations of dietary ractopamine did... |