Submitted to: Campylobacter Helicobacter and Related Organisms International Workshop
Publication Type: Abstract only
Publication Acceptance Date: 8/6/2007
Publication Date: 9/2/2007
Citation: Guerin, M.T., Martin, S.W., Reiersen, J., Berke, O., Mcewen, S.A., Bisaillon, J.R., Lowman, R., Michel, P., Edge, V., Stern, N.J., Hiett, K.L. 2007. A multi-level analysis of risk factors for campylobacter spp. in broiler chickens in iceland. Campylobacter Helicobacter and Related Organisms International Workshop. P 14, #O045. Interpretive Summary:
Technical Abstract: Introduction We carried out a longitudinal study of the broiler industry in Iceland between May 2001 and September 2004. Using multi-level statistical methods, our objective was to determine which aspects of the birds, their management and/or their housing may be most useful for applying interventions to reduce flock colonization with Campylobacter. Methods Pooled caecal samples were obtained from 1,425 flocks at slaughter and cultured for Campylobacter. Due to the strong seasonal variation in flock prevalence, analyses were restricted to a subset of flocks raised during the four summer seasons; 27% (217) of 792 flocks tested positive. Logistic regression, with random house and farm effects, was used to examine associations between flock status and several farm-, house- and flock-level variables, including temperature-related factors based on thresholds of fly activity. Results Risk factors included cleaning houses with geothermal water, cleaning/disinfecting boots before entering the house, increasing age at slaughter, increasing flock size, and increasing cumulative degree-days above an average temperature of 4.4'C during the 2 to 4 week period before slaughter. Protective factors included the presence of at least one cool day (a maximum temperature below 8.9'C) 2 to 4 weeks before slaughter, and the use of an official (municipal) treated water source compared to an untreated source. A non-official treated water source was marginally protective. Differences among farms accounted for a significant amount of the variation in flock status. Conclusion 1) Geothermal water use is likely a surrogate for regional agro-environmental Campylobacter pressure. Further studies directed toward identifying underlying environmental factors, and treatment of the water supply, may substantially reduce Campylobacter in broiler flocks in Iceland. 2) Additional interventions that require investigation include fly control during high risk periods (sustained high temperatures with minimal cool days), shipping flocks at a younger age, limiting flock sizes, and eliminating boot dips.