Study on partial replacement of fish meal with concentrated dephenolized cottonseed protein in feed ofPenaeus monodon

Abstract

The effects of partial replacement of fish meal with concentrated dephenolized cottonseed protein (CDCP) in feed on growth performance, feed utilization, nonspecific immune responses and gut morphology were studied in black tiger shrimp (Penaeus monodon) using 8-week feeding trials. Five isonitrogenous and isolipidic diets were formulated to contain five graded levels of CDCP (0%, 5%, 10%, 15% and 20%). Each diet was randomly assigned to triplicate groups of 30 shrimp (0.80–0.84 g). Maximum weight gain rate (WG), specific growth rate (SGR), survival rate (SR), apparent feed dry matter digestibility and the number of intestinal folds were recorded at 10% dietary CDCP. Dietary CDCP levels had no significant effect on serum superoxide dismutase (SOD) and malondialdehyde (MDA), (p > 0.05). Intestinal microstructures were positively affected by dietary CDCP at the optimal level of 10%, significantly increasing fold height and flod numbers (p < 0.05). Based on the growth performance, feed utilization, proximate composition, enzyme activities and gut morphology, the optimum dietary CDCP level for optimal growth of P. monodon was 10% of the dry diet, corresponding to the replacement ratio of fish meal 33.33%. The results provide a theoretical basis for the designing of feed formulation for black tiger shrimp (P. monodon).