Microbiological Flora of Aquacultured Hybrid Striped Bass

Aquacultured hybrid striped bass were examined for quantity and quality of microflora. Plate counts were performed at three temperatures (7, 22, and 35°C) under aerobic and anaerobic conditions. Bacterial loads on the skin, gills, and intestines were similar to those reported for wild fish. Plate counts performed at 22°C yielded the highest counts and the greatest variety of species. The predominant groups of bacteria isolated were Aeromonas spp. (27%), coryneforms (14%), Pseudomonas spp. (12%), Flavobacterium/Cytophaga/Sphingobacterium group (8%), Plesiomonas shigelloides (7%), Bacillus spp. (7%), and Enterobacteriaceae (6%). Human foodborne pathogens Listeria monocytogenes , Staphylococcus aureus , Shigella dysenteriae , Vibrio spp., and Yersinia pseudotuberculosis were also isolated. There were no indications, however, that pond-raised fish present a higher risk of foodborne illness than do wild fish.