Potential of several protein sources as fish meal substitutes in diets for large yellow croaker, Pseudosciaena crocea R.

A feeding experiment was conducted to evaluate the potential of replacing fish meal (FM, Diet 1) with soybean meal (SBM, Diet 2), meat and bone meal (MBM, Diet 3), poultry by-product meal (PBM, Diet 4), and peanut meal (PM, Diet 5) in practical diets of juvenile large yellow croaker, Pseudosciaena crocea. Five isonitrogenous and isoenergetic diets (43% crude protein and 20 kJ/g gross energy on dry matter basis) were formulated. Diet containing FM as the main protein source was used as a control (Diet 1). Diets 2–5 had 30% of the FM protein replaced with SBM, MBM, PBM, or PM protein. Each diet was randomly assigned to triplicate groups of 25 fish per cage (initial body weight 23.3 ± 0.96 g). Fish were maintained in sea floating cages (1.5 × 1.5 × 2.0 m), water temperature ranged from 27 to 30 C, salinity from 25 to 28‰ and dissolved oxygen content was more than 7 mg/L. Fish were hand-fed twice daily to apparently satiation for 8 wk. Fish fed Diets 1–4 showed no significant difference in survival, weight gain (WG) and specific growth rate (SGR), while fish fed Diet 5 showed significant inferior WG and SGR (P < 0.01). Carcass crude protein and crude lipid of the fish fed Diet 5 were significantly lower than those of the fish fed the other diets (P < 0.05). Carcass lysine content of the of fish fed Diet 5 showed slight, yet significantly decrease (P < 0.05), compared with those of the fish fed Diets 1–4, while other essential amino acids (EAAs) content showed no significant differences among the different treatments. Results of the present study indicate that about 30% of FM protein can be replaced by SBM, MBM, or PBM protein in large yellow croaker diets without adversely effecting growth.