The study investigated the effect of feeding restriction regimes on economic and productive performance of Nile tilapia Oreochromis niloticus. Sixty Nile tilapia fish were randomly classified into three groups (n=10/group) with similar initial body weight. Group I (Control group) was fed three times daily for 32 days. Group II was deprived for 4 days and then re-fed for 16 days, while Group III was deprived for 8 days and then re-fed for 32 days. The experiment was terminated after 10 weeks. All groups were fed on commercial diet at 2% of body mass. Indicate parameters measured were weight gain, feed efficiency, feed conversion ratio, economic conversion ratio and water quality. The above parameters were measured every 2 weeks. The results revealed that, after 64 days, Fishes which exposed to long starvation periods (8F:32R) consumed significantly (P= .01) more feed compared to other the restricted group (4F:16R). The highest feed efficiency was observed in fish exposed to 4F:16R. However, this group showed less feed intake than the 8F:32R and control groups. Moreover, cost benefit analysis under restriction indicated that, the highest return observed in control group and restricted fish for 4 days and the lowest in restricted fish for 8 days (P= .05). On the other hand, parameters of water quality (pH, Dissolved oxygen, Turbidity and Ammonia) were significantly (P= .01) affected by feed restriction regimes. Turbidity and ammonia levels were more in control group than the restricted groups.
Keywords: Cost-benefit analysis, Economic and productive performance, Feed restriction, Nile tilapia fish