The feasibility of partial replacement fish meal with poultry by‐products in practical diets of juvenile great sturgeon, <i>Huso huso</i> : Effects on growth performance, body composition, physiometabolic indices, digestibility and digestive enzymes
Mir Hamed Sayed Hassani, Akbar Banavreh, Ayoub Yousefi Jourdehi, Mahmoud Mohseni, Maryam Monsef Shokri, Hooshang Yeganeh Rastekenari
Abstract
To characterize the effects of a poultry by-product (PBM) on the gonadosomatic, physiometabolic indices, digestibility and digestive enzymes of juvenile Huso huso (28.42 ± 0.17 g), we procured six experimental diets with 0 (control), 20%, 40%, 60%, 80% and 100% PBM to replace fishmeal. After an 8-week feeding trial, results confirmed that the weight gain, the specific growth rate of fish fed the 80% and 100% diets were markedly inferior to other groups (p < 0.05). Also, the highest feed conversion ratio and the lowest protein efficiency ratio were observed in dietary of full replacement of fishmeal by PBM (p < 0.05). Triglyceride and cholesterol significantly increased in the PBM100 than the control and PBM20 (p < 0.05). Gastrointestinal enzyme activities were notably decreased in fish fed the diets of more than 60% substitution of fishmeal by PBM (p < 0.05). No statistical difference was observed in the digestibility of protein, dry matter, lipid and gross energy in fish fed up to 300 g/kg (PBM60) of PBM, while beyond this level, all of ADCs value reduced (p < 0.05). Taken together, the optimum range replacement by PBM was 235.9–251.8 g/kg in juvenile Huso huso diet based on the broken-line regression analysis.