Application of some corn processed wastes in grower diet of rainbow trout (Oncorhynchus mykiss)

Document Type : Nutrition

Authors

1 Bafgh Saltwater Fisheries Research Center, Fisheries Research Institute of Iran

2 Iranian Fisheries Science Research Institute, Tehran, Iran

Abstract

Growth performance of rainbow trout studied by use of bread and macaroni industries wastes in Grower diet (as carbohydrate source) replacement of wheat and corn. 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 macaroni wastes. Blank diet prepared as same as commercial common diet. 21 polyethylene net cages (1×1×1m) used for fish holding in a cement pond (30×3×1.2m) with 10l/s water flow. Each cage stoked by 20 fish with initial average weight of 85±5g. 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 6.8-8.5mg/l, respectively. The best growth performance belonged to diet 4, although results diets of 2, 4, 6, and blank had no significant differences (P>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<0.05).

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