Partial Replacement of Fish Meal with Meat-and-Bone Meal, Flash-Dried Poultry By-Product Meal, and Enzyme-Digested Poultry By-Product Meal in Practical Diets for Juvenile Red Drum

Abstract

To reduce long-term dependence upon fishery resources, we evaluated selected terrestrial by-products as alternatives to fish meal for rearing juvenile (mean weight, 2.3 ± 0.1 g) red drum Sciaenops ocellatus. Over a 6-week feeding trial, 10 test diets (basal diet and 9 test diets) were formulated on an isonitrogenous (44% gross protein) basis. The primary protein sources in the basal diet were fish meal and soybean meal, which were incorporated at 30 and 24.8 g/100 g of diet, respectively. Replacement of fish meal in the test diets ranged from 16.6% to 66.7%. Low ash meat-and-bone meal (MBM), flash-dried poultry by-product meal (PBM), and enzyme-digested poultry by-product meal (EPM) were used to replace the fish meal. All four MBM diets produced significantly lower weight gain compared with fish maintained on the basal diet. Feed efficiency (FE) and protein conversion efficiency (PCE) were similar for the 16.6% MBM diet and the basal diet, but higher levels of MBM produced significantly lower FE and PCE values. The PBM and EPM diets did not show any significant differences in percent weight gain, FE, or PCE compared with the basal diet. Based on these results, the use of high quality poultry by-product meals is a viable option in practical diets for red drum, whereas the MBM used in this study was not acceptable as a replacement for fish meal.