Comparative Bacteriological Analysis of Giant Freshwater Prawn ( Macrobrachium rosenbergii ) Cultured in South-Western Coastal Areas of Bangladesh

Abstract

Background and Objective: With changing pattern of culture practices in the coastal region of Bangladesh, the euryhaline giant freshwater prawn Macrobrachium rosenbergii has recently gained popularity among farmers of both semi-intensive and extensive culture systems to improve profitability. Since bacteria are the key player in aquaculture facilities governing health and quality of fish and prawn, comparative bacteriological analyses were undertaken to understand the suitable testing system of bacterial analysis for cultured freshwater prawn.Methodology: Both on-farm and laboratory conditions in low-resource settings were considered to monitor bacterial population in terms of bacterial count, gram staining and presence of enteric bacteria associated with prawn and its surrounding environment.Results: On-farm counting was about one log-unit lower total viable count in water, sediment and prawn samples compared to those of laboratory testing. The differences between on-farm and laboratory analysis probably occurred due to the time lapse during sample transportation. Study also showed that gram negative bacteria were dominant and enteric bacteria were present in both the prawn farms with more or less similar frequencies.Conclusion: It is concluded that the apparent difference in bacteriological condition of the two farms is possibly related to the differences in culture practices, environment and culture conditions and the study has recommended on-farm testing as an ideal bacteriological analysis method.