Application of some corn processed wastes in grower diet of rainbow trout (Oncorhynchus mykiss)
Subject Areas : New Technologies in Aquaculture Development
Keywords: growth performance, Keywords: Rainbow trout, Bread and pasta wastes, wheat and corn,
Abstract :
Abstract In this study, growth performance of rainbow trout by using two types of industrial wastes including waste grain processing by industry for bread and pasta as an alternative source of carbohydrate in grower diet, was studied in a completely randomized statistical design. Seven experimental diets were prepared. Amount of carbohydrate materials replacement in diets were: 1) 100% bread wastes 2) 50% bread wastes 3) 100% macaroni wastes 4) 50% macaroni wastes 5) 100% equal mix of bread and macaroni wastes and 6) 50% equal mix of bread and pasta wastes. Diets set by Lindo software. 21 polyethylene net cages (1×1×1 m) used for fish holding in a cement pond (30×3×1.2 m) with 10 l/s water flow. Each cage stoked by 20 fish with initial average weight of 85±5 g. Farming period was 75 days and in this period water temperature, pH and dissolved oxygen were 14.5±2°c, 7.5-8.8 and 6.8-8.5 mg/l, respectively. In this research some main growth equations (WG, PER, FCR, SGR, DP, CF) and economical factors were studied. Data were analyzed using SPSS software, Dankan analysis and also descriptive statistics. The best growth performance belonged to diet 4, although results diets of 2, 4, 6, and control no different (p < /em><0.05). In term of economic value of used diets, diets 2 had the best result. Carcass analysis in the end of experiment showed that carcass protein and ash contents in all of treatment were same but lipid content in treatments of 1, 3, and 5 were lower than other treatments (p < /em><0.05). Economic analysis showed, the superiority of the two treatments in which 50% of wheat and corn was replaced by bread wastes. According to the results, the use of mixed pasta and bread wastes instead of 50% wheat brings about good results in terms of growth performance and lower cost than the control diet and is recommended in diet of trout in grower stage.
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