Submitted to: Applied and Environmental Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/12/2004
Publication Date: 6/20/2005
Citation: Wesley, I.V., Muraoka, W.T., Trampel, D., Hurd, H.S. 2005. Effect of pre-slaughter events on prevalence of Campylobacter jejuni and Campylobacter coli in market-weight turkeys. Applied and Environmental Microbiology. 71(6):2824-2831. Interpretive Summary: Campylobacter is a major bacterial foodborne pathogen with consumption of raw contaminated poultry regarded as a major risk factor for human infections. The stress of perimarketing events--feed withdrawal, catching, crating, transport, and holding at the abattoir--prior to slaughter have been shown to alter the levels of Campylobacter in broilers. We report that 60-95% of market weight turkeys harbor Campylobacter, as determined by cloacal swabs of birds both prior to transport on the farm and after transport at the abattoir. We noted, however, that the population of C. coli increased after transport in three of the five trials. We also noted that the populations of C. coli were more diverse than those of C. jejuni, based on DNA profiles. Whether the shift in Campylobacter population dynamics may favor selection of more virulent strains or of bacteria with enhanced antimicrobial resistance is unknown.
Technical Abstract: The effects of perimarketing events which occur prior to slaughter, such as loading, transport, and holding at the abattoir, on the prevalence of the Campylobacter species, including Campylobacter jejuni and Campylobacter coli, were examined. Cloacal swabs from market-weight turkeys in each of five flocks were obtained on the farm prior to loading (Time 1, 120 swabs per flock) and after transport and holding at the abattoir (Time 2, 120 swabs per flock). A statistically significant increase in the overall levels of Campylobacter spp. was observed in cloacal swabs obtained from Flock 3 following transport (P < 0.01). At Time 2, an increase in the prevalence of C. coli was also noted for cloacal swabs from Flocks 3, 4, and 5 (P < 0.01). Neither the minimum time off of feed nor distance transported from the farm to the abattoir were correlated with the increase of C. coli prevalence. Similarly, responses to an on-farm management questionnaire failed to detect any factors contributing to the observed changes in Campylobacter spp. prevalence. Macrorestriction analysis with SmaI of Campylobacter spp. isolates recovered from Flock 5 indicated that C. coli was more diverse than C. jejuni at both Time 1 and Time 2 (P < 0.01), based on comparison of Sharon Indices of Diversity and Evenness.