Viability and release of Salmonella charity and Escherichia coli from oyster feces.

Sydney Rock oysters (Crassostrea commercialis) contaminated with Salmonella charity and Escherichia coli produced feces containing viable cells of these species. The level of these bacteria in the feces depended upon the level of oyster contamination. Both S. charity and E. coli were released from the feces into overlying seawater. The extent of release into seawater depended upon the physical state of the fecal material, water temperature, and the time of contact with the water. The viability of S. charity and E. coli associated with the feces and released into seawater decreased with time and was a function of seawater temperature. The association and release of bacteria from oyster feces has important implications in oyster purification and purification tank design and may lead to a recontamination of purified oysters.