Contamination of Salmonella blockley in the environment of a poultry farm.

Cecal and environmental samples were collected and examined for the presence of Salmonella on a farm where a high prevalence of Salmonella blockley in chickens was observed. Of 895 cecal and 525 environmental samples examined, 242 (27.0%) and 202 (38.5%) samples, respectively, yielded S. blockley. From the analysis of plasmid profile patterns, 11 different plasmid profile patterns were found among 444 isolates, with plasmid patterns c and d the most frequent among the isolates from ceca and the environment. Salmonella blockley was isolated from environmental samples such as floor litter, walls, drinking water, waste water, dust, and soil collected when barns were occupied and was positive in drinking water, waste water, and soil when samples were collected from empty barns with occupied neighboring barns, but it was negative in all environmental samples with the exception of soil when the environmental samples were collected from empty barns with empty neighboring barns.