RISK FACTORS FOR CAMPYLOBACTER SPP. COLONIZATION IN BROILER FLOCKS IN ICELAND

Authors: BARRIOS, P - UNIV OF GUELPH; REIERSEN, J - ICELAND VET SERV; LOWMAN, R - CANADIAN FOOD INSP SERV; BISAILLON, J - CANADIAN FOOD INSP SERV; MICHEL, PASCAL - HEALTH CANADA; FRIDRIKSDOTTIR, VALA - INST FOR EXP PATH; GUNNARSSON, E - INST FOR EXP PATH; Stern, Norman; BERKE, O - UNIV OF GUELPH; MCEWEN, S - UNIV OF GUELPH; MARTIN, W - UNIV OF GUELPH

Submitted to: Preventive Veterinary Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2006
Publication Date: 6/16/2006
Citation: Barrios, P.R., Reiersen, J., Lowman, R., Bisaillon, J.R., Michel, P., Fridriksdottir, V., Gunnarsson, E., Stern, N.J., Berke, O., Mcewen, S., Martin, W. 2006. Risk factors for campylobacter spp. colonization in broiler flocks in iceland. Preventive Veterinary Medicine. 74(4):264-278.

Interpretive Summary:

Technical Abstract: We sampled 1091 Icelandic broiler flocks at slaughter from May 2001 to December 2003 in order to determine the prevalence of, and investigate risk factors for, Campylobacter spp. at the flock level. Approximately 15% of the flocks gave a positive result, most (95%) of them raised during the period April to September. Multivariable analysis using logistic regression showed that the odds of flocks being positive increased with age and flock size. Importantly, vertical ventilation systems were strongly associated with positive flocks (OR = 5.3, p = 0.012), compared with horizontal ventilation systems. We found no evidence of Campylobacter being carried over from one flock to the next, and failed to reveal any association between positive flocks and the time interval between flocks, use at the hatcheries of eggs laid on the floor, or the number of catch lots a flock was divided into for slaughtering purposes. Interpretive Summary: Campylobacteriosis is one of the most frequently reported food borne bacterial diseases within the United States. The Centers for Disease Control suggest that broiler chickens are the most important single source involved with its transmission to humans. Therefore, we wanted to know the most important risk factors involved with flock contamination by Campylobacter. We closely monitored 1,091 broiler flocks in Iceland for colonization using cultural microbiological methods. Statistical analysis determined that production of flocks during April through September increased the risk for infection, as did age and flock size. Vertical ventilation systems (as compared to horizontal systems) were strongly associated with colonization. This may account for transmission from migratory birds. No evidence for colonization was found for time interval between flocks or number of catch lots per flock, nor was use of floor laid eggs from the hatcheries to populate broiler flocks. These observations provide Campylobacter risk factors involved in broiler production and should lead to reduced frequency of broiler colonization.