Feed quality can be measured with diet content of protein level, and feed cost can be greatly reduced if optimal dietary protein levels could be fed to the fishes. The primary goal of every researcher is to determine the optimum protein level of tilapia and increase farms’ profits. Decreasing the dietary protein level had more pressure on body protein because of the dietary nutrients needed to meet the demand of tissue protein synthesis, maintenance, and metabolism, causing the fish growth reduction and enhancing mortality. In contrast, the excess protein in the fish diet leads to making new proteins and the remainder would be directed toward the deamination of amino acids to produce energy consumption; thus, increasing the excretion of ammonia in the reared ponds . Furthermore, knowledge of feeding levels is important for achieving the best growth and feed efficiency and preventing water quality deterioration due to overfeeding.
A factorial experiment 2 × 2 was conducted to inspect two dietary protein levels with two feeding rates on performance and feed use of hybrid juvenile tilapia (Oreochromis nilotiucs × Oreochromis aurea). This trial was conducted in a fish feeding laboratory, Faculty of Aquaculture and Marine Fisheries, Arish University for 6 weeks. This trial examined two dietary protein levels, 27% and 34% CP with 5% and 7% of biomass, and each treatment was in triplicate. Twelve plastic tanks (54 × 38 × 28 cm: L × W × H) were used to accomplish this work. Fishes had an average initial weight of 7.5 ± 0.16 g and were stocked at 12 juveniles/tank. Fishes were fed three times daily and 6 days weekly. The water exchange rate was about 20% of water volume/tank every day. Water quality parameters were within the optimum limit for rearing tilapia during the experimental period (Table 1) . The results showed that dietary protein levels from 27% to 34% did not significantly affect growth and feed use (Table 2). However, 7% feeding rate had significantly higher growth parameters than 5% (Table 3). Statistical analysis of the interaction between dietary protein and feeding levels showed that fishes fed at 7% as the feeding level with dietary protein at 27% or 34% was significantly higher in growth than those fed at 5% with the same diets. Also, it confirmed the significant difference in specific growth rate and survival rate of fishes fed at 7% as feeding rate with any diet protein level (Table 4) . Thus, this study suggests that 27% CP with 7% as feeding rate is more for the best growth of hybrid tilapia juvenile under the same conditions of this trial.