Abstract:

As the bacteria infection in breeding stage of Macrobrachium rosenbergii could influence the metamorphosis rate of zoea, we collected the zoea, postlarva and their rearing water from four hatcheries at different time points during the breeding stage. The agar plate was used to isolate and culture to investigate the amounts of bacteria in the samples, the 16S rRNA sequence of the isolated dominant bacteria was analyzed, and the drug resistance of the dominant bacteria was analyzed. The results showed that the amounts of bacteria in postlarva and zoea were at a high level, and the variation of dominant bacteria was related to the season. Klebsiella aerogenes, Vibrio sp. and Aeromonas sp. were relatively common in the collected samples from these four hatcheries. The antibiotic sensitivity detection showed that the dominant bacteria of postlarva were all resistant to cephalexin and rifampicin, while the sensitive antibiotics were varied from different hatcheries. The results of this study provided a reference for the targeted prevention and control of bacterial infection in the breeding stage of Macrobrachium rosenbergii.

Key words: Macrobrachium rosenbergii, breeding stage, dominant bacteria, antibiotic sensitivity detection, 16S rRNA