Variations spatio-temporelles de la concentration de coliformes fecaux dans l'eau, les sediments et la chair des huitres cultivees, Crassostrea virginica

In Atlantic Canada, aquaculture of the American oyster Crassostrea virginica is a growing industry with significant economic potential.; The objective of the project is to increase the general understanding of spatial and temporal variations of faecal coliform concentrations in open, conditional and closed shellfish aquaculture zones. A comprehensive survey of faecal coliform contamination was undertaken in the Richibucto estuary (New Brunswick, Canada). The program considered various aspects as related to shellfish sanitation including whether: water quality is the most suitable indicator for shellfish contamination; sediments act as reservoirs for faecal coliform; the current classification method is the most suitable approach in describing fecal contamination in oysters; the current strategy is in fact the most effective one for year round conditions and if there are correlations between variations in water temperatures and particulate suspended matter and faecal coliform concentrations.; Results did not show any significant difference in faecal contamination between suspension and bottom-cultured oysters. Water contamination, in general, was significantly lower than in oysters and sediments. There was, however significant correlation in time with faecal contamination of oyster meats. When current thresholds for required closure are considered, our findings suggest that water is a questionable indicator of oyster sanitation. Our results do not support the criteria employed by the current classification system in the study area. We expect our findings will serve as an important source of information on faecal contamination, for industry as well as those agencies mandated with the application of the established Canadian Shellfish Sanitation Program. (Abstract shortened by UMI.)...