Efficacy of squid by-product hydrolysate supplementation on the growth performance, digestive enzyme activities and muscle growth-related genes expression of Penaeus monodon fed on plant protein-based diet

Abstract

AbstractThe efficiency of squid by-product hydrolysate supplementation in the diet of carnivorous black tiger shrimp (Penaeus monodon) has been evaluated for 8 weeks. A low fish meal diet, containing 5% fish meal (unsupplemented control), was formulated and supplemented with graded levels of squid by-product hydrolysate at 0.5% and 1%. A positive control with 22% fish meal as the main protein source was also prepared. The growth in terms of weight gain (WG) and specific growth rate (SGR), nutrient retentions, digestive enzyme activities and muscle growth-related genes expression has been evaluated. Results revealed that WG and SGR of shrimp fed on diets supplemented with 0.5% and 1% squid by-product hydrolysate (WG:534.02–555.07%, SGR:3.30–3.36% day−1) were comparable (p > 0.05) to the fish meal control (WG:544.03%, SGR:3.33% day−1) and higher (p 0.05) among treatments. Moreover, digestive enzyme activities (protease:1010.13–1503.45 Units mg−1protein, amylase:168.51–223.45 Units mg−1protein, lipase:4510.93–5380.82 Units mg−1protein) were not influenced (p > 0.05) by hydrolysate supplementations. These results suggest that the growth performance of P. monodon fed on a plant protein-based diet (with 5% fish meal) has improved upon the supplementation of at least 0.5% squid by-product hydrolysate in the formulated feed and is comparable to that of the shrimp fed the fish meal-based diet.

Keywords

• squid by-products
• plant protein-based diet
• Penaeus monodon
• shrimp nutrition
• nutrient retention
• digestive enzyme activities