GROWTH AND PRODUCTION OF QUICK GROWING SPECIES UNDER MONOCULTURE AND POLYCULTURE SYSTEMS IN THE SEASONAL WATERBODY OF HAOR VILLAGE NOAGAON, SUNAMGANJ

Abstract

The study was conducted to assess the growth, survival and production performance of Thai sarpunti (Puntius gonionotus Bleeker), tilapia (Oreochromis niloticus Lin.) and rui (Labeo rohita) under monoculture and polyculture systems in 9 farmers’ seasonal ditches over the period of 120 days from January to April 2016. Experimental ditches were cleaned manually and were limed at the rate of 250 kg ha-1 of quicklime (CaO). These were then fertilized with urea and triple supper phosphate (TSP) at the rate of 25 kg ha-1. Nine ditches were divided into three treatments each having three replicates and each ditch was stocked with fish fry/fingerlings at the rate of 40,000 nos ha-1. Stocked fishes were fed with rice bran and wheat flour as supplemental feed at the decreasing rate of 10-5% of total biomass for twice daily. Water quality parameters such as temperature, transparency, dissolved oxygen, pH, total alkalinity and ammonia were within suitable range for fish culture and any stress did not observe in fishes. The highest average final weight of sarpunti (122.32 g), tilapia (102.58 g) and rui (120.0 g) was obtained in T1, T2 and T3, respectively. It was found that the average weight of sarpunti was decreased with the increases of fish species. The survival of all fish species was found higher in T3 than T1 and T2. Among the treatments food conversion ratio (FCR) of sarpunti was found lower in T1 (1.26) compared to T2 (1.38) and T3 (1.52), respectively. Comparatively higher FCR of tilapia was estimated in T3 (2.12) than that of T2 (1.52). FCR of rui was found lower (1.10) than other two fish species under different treatments. Significantly higher production of sarpunti was secured in T1 (3,446.13 kg ha-1) than T2 (2,942.6 kg ha-1) and T3 (2,804.1 kg ha-1). It was observed that tilapia production was better in T2 (2,786.07 kg ha-1) than T3 (2,172.52 kg ha-1). The combined production of sarpunti, tilapia and rui was significantly (p<0.05) higher in T3 (8,341.41 kg ha-1) followed by T2 (5,728.67 kg ha-1) and T1 (3,446.13 kg ha-1). The highest cost benefit ratio was achieved in T3 (1.64:1) that of T1 (1.25:1) and T2 (1.30:1). From the results of the present study it may be concluded that polyculture of sarpunti, tilapia and rui in seasonal ditches is the best than other techniques for better fish production as well as for higher economic return in haor areas. Therefore, the polyculture practice of sarpunti, tilapia and rui at a stocking density of 40,000 ha-1 and at a ratio of 2:1:1 may be suggested to disseminate at the fish farmers’ level for boost up fish production in manifolds using the unutilized ditches.