الفهرس | Only 14 pages are availabe for public view |
Abstract In aquaculture industry should be replace the traditional highly-cost marine protein ingredients such as fish meal by other cheaper alternative ingredients. In Egypt, there is a strong attention within the aquaculture industry to utilize high nutritional and more economical protein sources to replace the traditional marine protein ingredients such as fish meal (FM). However the very good nutritive value of FM, its price are quite high as well as the inconstant production and uncertain availability in the aftertime. Accordingly, to allow the sustainable expansion of the aquaculture industry, it is of great significance to explore other protein alternatives to FM in aqua diets. The present study was conducted in two experiments Experiment I It was conducted to determine the effect of rice protein concentrate as a replacement of fish meal in the diets of Nile tilapia (O. niloticus) fingerlings and study their effects on growth performance, blood biochemical parameters, immune status, body composition, nutrient digestibility, and economic efficiency. A total of 240 Nile tilapia (O. niloticus) with an average body weight of 40±0.2 g were used. The fish were randomly divided into 4 equal groups (Each group contain 3 replicates, each replicate contained 20 fish). A basal control diet was formulated with zero replacement of fish meal (G1) and other experimental groups (G2-4) received a basal diet containing fishmeal replaced with 25%, 50%, and 100% RPC, respectively. The fish were fed isonitrogenous, isocaloric diets twice daily at a rate of 3% of body weight for 90 days. The obtained results revealed that: 1) Body-weight gains weren’t affected by replacing fish meal by RPC 100% compared to the control, while at this level of replacement, feed intakes, and feed conversion ratios were higher than in the control group. Protein efficiency ratios and protein retention efficiencies were decreased by replacement fish meal with RPC at 25%, 50%, and 100% than the control group. |