The potential of mixed culture of genetically improved farmed tilapia (Oreochromis niloticus) and freshwater giant prawn (Macrobrachium rosenbergii) in periphyton-based systems

Abstract

The production performance of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in periphyton‐based systems were studied in farmers' ponds at Mymensingh, Bangladesh. Fifteen ponds (200–300 m2 area and 1.0–1.5 m in depth) were used to compare five stocking ratios in triplicate: 100% GIFT, 75% GIFT plus 25% prawn, 50% GIFT plus 50% prawn, 25% GIFT plus 75% prawn and 100% prawn. Ponds were stocked at a total density of 20 000 GIFT and/or prawn ha−1. Bamboo poles (mean diameter 6.2 cm and 5.5 pole m−2) were posted in pond bottoms vertically as periphyton substrate. Periphyton biomass in terms of dry matter (DM), ash‐free DM and chlorophyll a were significantly higher in ponds stocked with prawn alone than in ponds with different combinations of GIFT and prawn. Survival of GIFT was significantly lower in ponds stocked with 100% GIFT (monoculture) whereas, that of prawn was significantly higher in its monoculture ponds indicating detrimental effects of GIFT on prawn's survival. Individual weight gains for both species were significantly higher in polyculture than in monoculture. The highest total fish and prawn yield (1623 kg GIFT and 30 kg prawn ha−1) over 125–140 days culture period was recorded in ponds with 75% GIFT and 25% prawn followed by 100% GIFT alone (1549 kg ha−1), 50% GIFT plus 50% prawn (1114 kg GIFT and 68 kg prawn ha−1), 25% GIFT plus 75% prawn (574 kg GIFT and 129 kg prawn ha−1) and 100% prawn alone (157 kg ha−1). This combination also gave the highest economic return. Therefore, a stocking ratio of 75% GIFT plus 25% prawn at a total density of 20 000 ha−1 appeared to be the best stocking ratio in terms of fish production as well as economics for a periphyton‐based polyculture system.

Impacts of Inclusion of Column Feeder Rohu (Labeo Rohita) at Different Stocking Densities on Growth and Production in Freshwater Prawn-Finfish Polyculture System

“…The mean survival rate of prawn in the present study was significantly higher in treatment R 0 (63.6 ± 1.1 %). The overall survival of prawn (50 to 64%) in the present experiment was more or less similar to the reported values in earthen ponds: 62% (Kumar et al, 2000), 52 to 55% (Mazid and Mahmud, 1994) and 57 to 66% (Uddin et al, 2006).…”

Effects of C/N controlled periphyton based organic farming of freshwater prawn on water quality parameters and biotic factors

“…As prawn grew its increased grazing pressure led to reduced periphyton biomass. Uddin et al (2006) reported that freshwater prawns may feed selectively on periphyton. It may have picked preferentially on animal portion and detrital aggregates rather than picking up the mixed biomass.…”

Strain performance of tilapia in freshwater prawn polyculture

“…Prawn (Macrobrachium rosenbergii) polyculture has a potentially higher net return than prawn monoculture (Rouse and Stickney, 1982). Culture of prawn with fish also improves the ecological balance of the pond water, preventing the formation of massive algal blooms (Cohen et al, 1983;Uddin et al, 2006). M rosenbergii is a benthophagic omnivore an excellent species for polyculture along with tilapia (Alam et al, 2001).…”

“…Similarly, it can be positively presumed that the culture of freshwater prawn for export market and tilapia in the same pond for household consumption may be an innovative option for fish farmers. Contrariwise, tilapia may exhibit negative impact on prawn survival that may hamper total production (Garcia-Perez et al, 2000;Uddin et al, 2006). Therefore, we compared the growth performance of GIFT and Chitralada in freshwater prawn culture system with a view to finding better performed strain, and simultaneously, we evaluated the effect of tilapia addition on prawn production performance.…”