Prevalence of thermophilic Campylobacter spp. in broiler flocks with follow-up of flock specific clones from farm through slaughter to retail products using pulsed field gel electrophoresis (PFGE)

摘要

In Germany campylobacteriosis is the second most frequent cause ofgastrointestinal infections. Campylobacteriosis in man is mainly afood-borneinfection, in which raw or undercooked poultry meat play an importantrole.Against this backround broiler flocks were screened to assess theircampylobacter carriage. In addition, the spread of spp.duringthe slaughtering process was surveyed. The main focus of this study wasthedetection of same genotypes in broiler flocks on farm level as well asin theslaughtering process up to the end-products. Therefore broiler flocksweresampled on farm level and at various stages throughout processing.Selectedcampylobacter isolates were genotyped by pulsed-field gelelectrophoresis(PFGE). Campylobacter carriage of flocks showed seasonal variation,with thehighest contamination rate during the period June to August. Althoughthehygienic measures in the broiler farms differed, no significantdifferenceconcerning contamination of the broiler flocks with spp.wasobserved. The broiler flocks were colonized by a limited number ofclones. Theresults also indicated that some campylobacter clones were more robustandsurvive poultry processing better than others. The fact, that indifferent flocksisolates of clonal origin could be detected during the same rearingperiod,suggests a transmission between the broiler flocks or an intermittentcommonexternal campylobacter source. In some cases isolates of clonal origincould bedetected in various farms during different rearing periods. This resultsuggeststhat some clones of spp. remain genetically stable over alonger time period and geographical distance. At the abattoir spp.were isolated from all sampling stages along the processing line whenslaughteringa positive flock. No hygienic barriers against the spread ofcampylobacter duringthe slaughtering process could be detected. Neither scalding nor dryingof thecarcass-surface could prevent the spread of spp. Mostisolatesat the abattoir belonged to the same genotype as the farm isolates fromthe flocksslaughtered. This result indicates that positive flocks are responsiblefor thecontamination of different stages in the abattoir. It was also possibleto detectflock-specific clones on contaminated giblets and end-products. Itappeared thatsome campylobacter clones can carry over onto the carcasses ofsubsequent flocks.Therefore it can be suggested that cross-contamination betweendifferentflockscan occur during processing. In this study PFGE appeared to be usefulforepidemiological analysis of strains of and .Intervention-proceduresat farm level have to be studied further. The effectiveness of stricthygienic practicesin farms as well as in abattoirs has to be evaluated. Also, adequateconsumerinformation on proper handling of poultry meat is needed.