In Vivo And In Vitro Protein Digestibility In Juvenile Bagrid Catfish Mystus Nemurus (Cuvier And Valenciennes 1840) Fed Soybean Meal-Based Diets

Abstract

In vivo and in vitro protein digestibility of 0% to 60% soybean meal protein (SBM) substitution from fishmeal protein was conducted for bagrid catfish Mystus nemurus juveniles. Seven experimental diets containing 35% protein and 15% lipid were fed to bagrid catfish to determine the in vivo protein digestibility. In vitro methods were determined using pH stat, pH shift, spectrophotometric assay and sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS-PAGE) with different enzyme mixtures (crude intestinal extract of bagrid catfish, Lazo 1-enzyme, Hsu 3-enzyme, Saterlee 4-enzyme). In vivo and in vitro protein digestibility decreased with increased SBM protein substitution with highest tolerance level of 10% (in vivo). pH stat and pH drop methods showed the highest degree of hydrolysis (DH) and relative protein digestibility (RPD) using Saterlee 4-enzyme system.