Short communicationThe quantitative and qualitative recovery of Campylobacter from raw poultry using USDA and Health Canada methods

- Two enrichment broths and direct plating were compared for the detection of Campylobacter from chicken carcass rinses.
- The Campylobacter prevalence on chicken carcases was 34.7%, 39.2% and 39.3% for direct plating, the US enrichment method and Health Canada enrichment method, respectively.
- Both enrichment methods showed significantly greater numbers of positives than direct plating.
- From direct plating the Campylobacter concentration ranged from 0-230 CFU ml−1 with an average of 71.6 CFU ml−1.

Harmonisation of methods between Canadian government agencies is essential to accurately assess and compare the prevalence and concentrations present on retail poultry intended for human consumption. The standard qualitative procedure used by Health Canada differs to that used by the USDA for both quantitative and qualitative methods. A comparison of three methods was performed on raw poultry samples obtained from an abattoir to determine if one method is superior to the others in isolating Campylobacter from chicken carcass rinses. The average percent of positive samples was 34.72% (95% CI, 29.2-40.2), 39.24% (95% CI, 33.6-44.9), 39.93% (95% CI, 34.3-45.6) for the direct plating US method and the US enrichment and Health Canada enrichment methods, respectively. Overall there were significant differences when comparing either of the enrichment methods to the direct plating method using the McNemars chi squared test. On comparison of weekly data (Fishers exact test) direct plating was only inferior to the enrichment methods on a single occasion. Direct plating is important for enumeration and establishing the concentration of Campylobacter present on raw poultry. However, enrichment methods are also vital to identify positive samples where concentrations are below the detection limit for direct plating.