Comparison of the survival, growth and yield of red swamp crayfish and white river crayfish in monoculture and polyculture systems

摘要

Red swamp crayfish (Procambarus clarkii) and white river crayfish (P. acutus acutus) production for monoculture and polyculture systems were compared. The experiment consisted of three treatments with six replicates each. The stocking rates were 43 crayfish/m2 in 0.18-m2 tanks fitted with a stand of green rice. Each tank contained six crayfish, either six individuals of the same species or three individuals of each species. The mean stocking size for monoculture and polyculture were 32.6 ± 0.05 and 33.0 ± 0.07 mm total length, respectively. Survival and growth was assessed at 30-day intervals over a 90-day experimental period. Survival of two species was the same in the monoculture system (62.5%). Survival of P. clarkii in the polyculture system (25.0%) was significantly lower than in the monoculture system (62.5%), whereas P. acutus acutus survived at similar rate in the polyculture system (41.7%) and monoculture system (62.5%). Survival was lower but growth was higher in the polyculture system than in the monoculture system for both species. Growth of P. acutus acutus in the polyculture system was significantly greater than in the monoculture system. No difference was observed in the growth of P. clarkii between polyculture and monoculture and the overall growth of P. acutus acutus and P. clarkii was similar for the 90 days. Yield did not differ significantly between monoculture and polyculture systems (P < 0.05). Total yields were in 1.15 kg/ha in monoculture and 1.18 kg/ha in polyculture.