|Rawles, Steven - Steve|
Submitted to: International Sustainable Marine Fish Culture Conference and Workshop Book of Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 10/5/2005
Publication Date: 10/19/2005
Citation: Rawles, S.D., Riche, M.A., Webb, J., Gaylord, T.G., Freeman, D.W., Davis, M. 2005. Evaluation of poultry by-product meal in commercial diets for hybrid striped bass in recirculated tank production [abstract]. International Sustainable Marine Fish Culture Conference and Workshop Book of Abstracts. p. 15. Interpretive Summary:
Technical Abstract: The efficacy of replacing fishmeal with petfood grade poultry by-product (PBM-PFG) on an ideal protein basis in commercial diets for hybrid striped bass (HSB) was evaluated under production conditions. A generic production diet (GEN) for HSB was formulated to contain 40% protein, 12% lipid and 3.7 kcal/kg. Protein in the GEN diet was supplied by a mix of animal and plant sources typically used by the industry that included more than 20% menhaden fishmeal and less than 10% PBM-PFG. A positive control diet (GEN+AA) was formulated by supplementing the GEN diet with feed-grade Met and Lys to match those levels had all protein been provided by HSB muscle. Substitution diets were formulated by replacing 35% or 70% of fishmeal in the GEN diet with PBM-PFG on a digestible protein basis and then supplementing with Met and Lys (designated 35PBM and 70PBM, respectively) as needed to maintain equity with the GEN+AA diet. Diet formulation and extrusion were conducted by a commercial mill. Fish (87 g mean fish weight) were stocked into 12 indoor, 8-m3 round tanks. comprising 3 replicated commercial-scale recirculating systems, of 4 tanks Each diet was represented by one tank/system. Diets were fed at a constant percent of body weight per day for the 24-wk trial. Diet composition significantly (P < 0.05) influenced final weight, weight gain, yield, hepatosomatic index and intraperitoneal fat ratio, but did not significantly alter feed conversion, survival, and muscle ratio. Fish fed the 35PBM diet performed as well as fish fed either generic diet; whereas fish fed the 70PBM diet performed poorer. This experiment clearly demonstrates that poultry by-product can be used as an alternative to fish meal in HSB diets. These results should decrease the costs of feed at the commercial level and reduce the need for fish meal, which is a limited resource.