| Popis: |
The production performance of Macrobrachium rosenbergii was compared in monoculture and polyculture systems with Indian major carps, Labe° rohita and Catla catla. The stocking density of prawn in monoculture was 13,545/ha; in polyculture the prawn was stocked at 8,645/ha while rohu and catla were each equally stocked at 2,470/ha. In monoculture, the initial weight of prawn was 4.13 ± 0.15 g and in polyculture system the average initial weight of prawn, rohu and catla were 4.10 ± 0.10, 68.0 ± 3.93 and 73.33 ± 3.05 g respectively. The final average weight of M. rosenbergii was 103.03 ± 6.80 and 92.83 ±3.55 g in monoculture and polyculture ponds respectively. The final average weight of rohu and catla were obtained at 278.56 ± 10.37 and 262.81 ± 11.62 g respectively. In both the systems, fertilizer and supplementary feed were used. The survival rate of prawn in monoculture and polyculture were found at 65% and 75% respectively; survival for both rohu and catla was obtained at 90%. The total production of prawn in monoculture and polyculture systems were 906.8 and 605.18 kg/ha respectively where the production of rohu and catla in polyculture were 619.1 and 584.2 kg/ha respectively. The average production costs in monoculture and polyculture systems were 149,510.7 Tk/ha and 150,058 Tk/ha respectively. In monoculture and polyculture systems the gross incomes were 255,650 and 295,066 Tk/ha respectively. The net incomes for the systems were 106,139.3 and 145,008 Tk/ha respectively. The study concluded that the polyculture of M. rosenbergii is comparatively more preferable in traditional and improved traditional polyculture systems. |
