Aims: To determine the flock prevalence and to estimate the within flock prevalence of Campylobacter in broiler flocks from different rearing systems, and to determine the antimicrobial susceptibility of Campylobacter isolates to selected antimicrobial substances.

Methods and Results: One hundred and sixty broiler flocks originating from organic, conventional and extensive indoor production farms were investigated for the presence of Campylobacter at the time of slaughter. Campylobacter isolates from a subsample of positive flocks were subjected to susceptibility testing. Campylobacter spp. were isolated from 100% of organic broiler flocks, from 36·7% of conventional broiler flocks and from 49·2% of extensive indoor broiler flocks. Six of 62 Campylobacter isolates were resistant to one or more of the antimicrobials tested.

Conclusions: These results indicate that the special characteristics of organic broiler production provide a high prevalence of Campylobacter-positive flocks. Antimicrobial resistance was scarce among Campylobacter isolates from all rearing systems.

Significance and Impact of the Study: Organic broiler flocks constitute a strong potential for introduction of Campylobacter to the processing line upon arrival at slaughter.