Abstract
An experiment was conducted in on-farm seasonal ponds of the Rangpur region to assess the growth and yield performance of Angra labeo fish in polyculture system and to determine the optimal species combination for semi-arid zones of Bangladesh. The study involved three treatments (T1, T2 and T3), each replicated, with Angus stocked at densities of 150, 200, and 250 individuals per decimal, respectively. Each treatment also included 10 Indian major carp (Catla), 5 Chinese carp (Silver carp), 10 Olive barb (Sarpunti) and 5 GIFT tilapia per decimal. After 150 days of culture, the average final weight of Angus were 21.10±1.20 g (T1), 25.40±1.0 g (T2) and 23.30±1.10 g (T3) with corresponding length of 16.30±0.20 cm, 17.20±0.03 cm and 16.60±0.04 cm. Initial weight and length were 0.50±0.1 g and 2.50±0.2 cm. T2 showed significantly higher weight gain (24.90±2.04 g), specific growth rate (2.61±0.2) and feed conversion ratio (1.74±0.01) compared to other treatments. Production of other fish species was also satisfactory: 4065±21 kg/ha (T1), 4306±20 kg/ha (T2), and 4157±19 kg/ha (T3). T2 yielded the highest total fish production (5372.40±24.7 kg/ha), Angus fish yield (1066.50±17.5 kg/ha) and benefit-cost ratio (1.43±0.04), with a gross margin of 455400±3690 BDT per hectare. Water quality remained suitable throughout the study. These findings suggest that the T2 combination is ideal for profitable polyculture in seasonal ponds of semi-arid zone of Bangladesh.