title: Explanatory Variables Associated with Campylobacter and Escherichia coli Concentrations on Broiler Chicken Carcasses during Processing in Two Slaughterhouses.
abstract: This study aimed at identifying explanatory variables that were associated with Campylobacter and Escherichia coli concentrations throughout processing in two commercial broiler slaughterhouses. Quantative data on Campylobacter and E. coli along the processing line were collected. Moreover, information on batch characteristics, slaughterhouse practices, process performance, and environmental variables was collected through questionnaires, observations, and measurements, resulting in data on 19 potential explanatory variables. Analysis was conducted separately in each slaughterhouse to identify which variables were related to changes in concentrations of Campylobacter and E. coli during the processing steps: scalding, defeathering, evisceration, and chilling. Associations with explanatory variables were different in the slaughterhouses studied. In the first slaughterhouse, there was only one significant association: poorer uniformity of the weight of carcasses within a batch with less decrease in E. coli concentrations after defeathering. In the second slaughterhouse, significant statistical associations were found with variables, including age, uniformity, average weight of carcasses, Campylobacter concentrations in excreta and ceca, and E. coli concentrations in excreta. Bacterial concentrations in excreta and ceca were found to be the most prominent variables, because they were associated with concentration on carcasses at various processing points. Although the slaughterhouses produced specific products and had different batch characteristics and processing parameters, the effect of the significant variables was not always the same for each slaughterhouse. Therefore, each slaughterhouse needs to determine its particular relevant measures for hygiene control and process management. This identification could be supported by monitoring changes in bacterial concentrations during processing in individual slaughterhouses. In addition, the possibility that management and food handling practices in slaughterhouses contribute to the differences in bacterial contamination between slaughterhouses needs further investigation.
authors.affiliation: Division Veterinary Public Health, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508 TD, The Netherlands.|MEYN Food Processing Technology B. V., Oostzaan, 1511 MA, The Netherlands.
authors.forename: Ewa
authors.initials: E
authors.lastname: Pacholewicz
authors.affiliation: Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, 3720 BA, The Netherlands.
authors.forename: Arno
authors.initials: A
authors.lastname: Swart
authors.affiliation: Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, 3508 TD, The Netherlands.|Central Veterinary Institute of Wageningen UR, Lelystad, The Netherlands.|WHO-Collaborating Center for Campylobacter/OIE Reference Laboratory for Campylobacteriosis, Utrecht, The Netherlands.
authors.forename: Jaap A
authors.initials: JA
authors.lastname: Wagenaar
authors.affiliation: Division Veterinary Public Health, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508 TD, The Netherlands.
authors.forename: Len J A
authors.initials: LJ
authors.lastname: Lipman
authors.affiliation: Division Veterinary Public Health, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508 TD, The Netherlands.|Emerging Pathogens Institute and Department of Animal Sciences, University of Florida, Gainesville, Florida 32610-0009, USA.
authors.forename: Arie H
authors.initials: AH
authors.lastname: Havelaar
mesh_terms: D000003:Abattoirs; D000818:Animals; D002167:Campylobacter; D002645:Chickens / Q000382:microbiology; D004926:Escherichia coli; D005506:Food Contamination; D005511:Food Handling; D005516:Food Microbiology; D008460:Meat / Q000382:microbiology
keywords: Poultry; Processing hygiene; Risk factors