Of the farms sampled, the majority of positive Salmonella findings were isolated from swine farms (57.3%). The occurrence of Salmonella was lower on dairy farms (17.9%), poultry farms (16.2%), and beef cattle farms (8.5%).
The results of this study suggest that reservoirs of Salmonella populations still exist in animal production facilities. Data showed that the surrounding farm environment could be an important source of contamination.
In the study, farm samples were collected quarterly from 18 different farms across five states (Tennessee, North Carolina, Alabama, California, and Washington) over a 24-month period.
The samples were analysed for the presence of Salmonella by means of the
US Food and Drug Administration’s Bacteriological Analytical Manual methods optimised for farm samples.
Salmonella isolates were characterised by automated riboprinting. Salmonella serovars were recovered from 4.7% of all samples. The most commonly isolated serovar was Salmonella Anatum (48.4%), which was isolated notably more frequently than the next most common Salmonella serovars, Arizonae (12.1%) and Javiana (8.8%).