The present study was conducted to determine the performance of Nile tilapia (Oreochromis niloticus) in rice–fish culture system. Six rice fields (1 feddan for each field) were cultivated with rice and divided into two groups, the first group (three fields) served as control (without fish) and the second group were stocked with Nile tilapia (1000 fingerlings/feddan). The growing season for tilapia fish was 90 days.
Results obtained can be summarized as follows:
- Water dissolved oxygen and pH in control fields (rice without fish) were higher than that obtained for treated fields (rice with fish) while water temperature, ammonia, alkalinity, phosphorus, salinity and nitrate were higher in treated fields.
- The average count of phytoplankton organisms (chlorophyta, cyanophyta and bacillarophyta) were higher in control fields compared to the treated fields and the same trend was also obtained for zooplankton groups (rotifera, copepoda and cladocera).
- Average body weight of Nile tilapia increased from 4.08 to 81.97 g, body length increased from 3.86 to 12.71 cm and condition factor decreased from 7.09 at the beginning to 3.99 at harvesting.
- The average daily weight gain ranged from 0.66 to 1.04 g with an average of 0.87g during the whole experimental period.
- Rice-fish integration system increased the rice yield by 148 kg/feddan beside 77.9 kg fish/feddan.
- Net returns were 831.6 and 1239.25 L.E./feddan for control and treatment (integration system), respectively.