Distribution of Campylobacter spp. in selected US poultry production and processing operations

A study was conducted of 32 broiler flocks on eight different farms, belong ing to four major U.S. producers. The farms were studied over I complete ca lendar year. Overall, 28 (87.5%) of the flocks became Campylobacter positiv e, and only four (12.5%) remained negative throughout the 6- to 8-week rear ing period. In the majority of flocks, sampled every 2 weeks throughout pro duction, Campylobacter-positive fecal and cecal samples were not detected u ntil 4 to 8 weeks of age. In only six of the flocks were environmental samp les found to be positive before shedding of Campylobacter was detected in t he birds. Even in some of the Campylobacter-negative flocks, contamination of the rearing environment was positive for Campylobacter but did not resul t in the birds subsequently excreting the organism. These findings are disc ussed in relation to U.S. husbandry practices and present uncertainty about sources of Campylobacter infection for poultry flocks. Birds were often tr ansported to the processing plant in coops that were already contaminated w ith Campylobacter, and the organisms were sometimes found in samples of sca ld water and chill water. After chilling, the proportions of Campylobacter- positive carcasses from different producers ranged from 21.0 to 40.9%, whic h is lower than in other studies, and possible reasons are considered.