Quality evaluation of some animal protein sources for rainbow trout Oncorhynchus mykiss.

Abstract

The quality of four kinds of animal protein source (white fish meal, brown fish meal, meat meal, and meat & bone meal) was evaluated on the basis of weight gain, protein digestibility, PER, NPU, and BV in rainbow trout. Four feeding experiments were con-ducted for 20days with diets containing one of these ingredients as the sole protein source at different protein levels in addition to a non-protein diet. Relatively, high values of protein digestibility of white fish meal (92%), brown fish meal (90%), and meat meal (91%) were obtained; meat & bone meal (78%) alone being slightly low. The nutritional quality of brown fish meal is almost comparable to that of white fish meat. The values for PER, NPU, and BV of these fish meats were found to be higher than meat meal and meat & bone meal; increasing with decreasing dietary protein levels in contrast to meat meal and meat & bone meal. These results have demonstrated that brown fish meal is as good as white fish meal in its nutritional value but meat meal and meat & bone meal performs lower probably due to their poor amino acid profile.