Production performance of largemouth bass Micropterus salmoides and water quality variation in monoculture, polyculture and integrated culture

A 74-day experiment was conducted to evaluate the production performance and water quality variation in three types of farming system for largemouth bass Micropterus salmoides. The tested aquaculture models included monoculture of largemouth bass (MC), polyculture of largemouth bass, gibel carp Carassius auratus gibelio and silver carp Hypophthalmichthys molitrix (PC), and integrated culture of largemouth bass, gibel carp, silver carp and freshwater pearl mussel Hyriopsis cumingii (IC). The ratio of largemouth bass, gibel carp and silver carp was 30:2:1 in the PC model, and the ratio of largemouth bass, gibel carp, silver carp and mussel was 30:2:1:5 in the IC model. The largemouth bass were fed with formulated feed twice daily. No significant differences were found in weight gain and yield of largemouth bass, total fish yield, nitrogen (N) and phosphorus (P) utilization efficiencies, N and P wastes, pH, nitrite, nitrate, reactive phosphate, total nitrogen, total phosphorus, total organic carbon, chemical oxygen demand, 5-day biochemical oxygen demand, chlorophyll a, primary productivity among the MC, PC and IC models. The ammonia was lower, while the dissolved oxygen was higher in the PC tanks than in the MC tanks. These results suggest that the environment situation was better in the PC tanks relative to that in the MC tanks. The present study reveals that the PC model should be a way to optimize the aquaculture model for commercial largemouth bass farming.