Effects of fish meal replacement with poultry by-product meal on growth performance, hematological indices and serum biochemical parameters in sobaity sea bream (Sparidentex hasta, Valenciennes 1830) juveniles

Finding economically viable and environmentally friendly protein sources to fish meal (FM) replacement in carnivorous fish feeds is one of the main challenges for the sustainability of the aquaculture industry. In this study, FM was replaced by Poultry by-product meal (PBM) levels of 0 (control), 15, 25, 35, 45 and 55% in Sparidentex hasta formulated diets. Sobaity sea-bream with an average initial weight of 29.27±0.06g and standard length of 8.7±0.36cm were randomly assigned to 18 tanks (300L) at stocking density of 20 fish per tank (6 treatments, triplicate) and were fed with experimental diets for 60 days. At the end of feeding trial, no significant reduction were observed in growth indices between the control and the fish fed up to 55% replacement. Hematocrit, hemoglobin, MCHC and serum albumin, globulin, total protein, glucose, urea and acid uric, aspartate aminotransferase had no significant differences between fish fed the PBM based diets and control diet (P>0.05). Serum alkaline phosphatase, cholesterol and calcium showed higher value in PBM diets than control, although triglyceride was higher in control diet than PBM diets. The results indicated that FM can be substituted successfully by PBM in the diet of S. hasta juveniles up to 45% without adverse effects on serum biochemical parameters