The effects of Campylobacter numbers in caeca on the contamination of broiler carcasses with Campylobacter

Abstract

For the presence and number of Campylobacter, 18 broiler flocks were sampled over a period of 18 months. A total of 70% of the flocks were positive for Campylobacter, with higher prevalence found in summer and autumn, compared to winter and spring. Positive flocks showed contamination rates above 90%, in negative flocks this was lower, mostly below 50%. The enumeration showed a decrease in Campylobacter during processing of positive flocks. The numbers were highest in carcasses after scalding/defeathering (mean 5.9 log 10 cfu/carcass) and dropped by 0.7 log 10 cfu/carcass after chilling. A positive correlation was observed between the number of Campylobacter present in the caeca and the number of bacteria present on carcasses and cut products. When a negative flock was slaughtered after Campylobacter positive flocks, the number of positive samples was higher compared to the case when a negative flock had been slaughtered previously. C. jejuni was isolated from 73.6% of the poultry samples.