Resistance to quinolones in XXXX and Campylobacter coli from Danish broilers at farm level.

@entity14116 @entity802 @entity5363 @entity1536
AIMS: To investigate the prevalence of @entity1536 resistance among @entity5363 and Camp. coli isolates from Danish poultry at the farm level, as well as for the whole country. METHODS AND RESULTS: Data and isolates were collected from a national surveillance of @entity5363 in poultry. @entity1536 resistance was investigated by determination of minimum inhibitory concentration (MIC) to @entity802 and @entity14116 . Among Camp. @entity5363 and Camp. coli combined, 7.5% were resistant to @entity802 . @entity1536 resistance varied considerably from farm to farm, with 0% on some farms and almost 100% on others, but the resistance was evenly distributed geographically. With respect to isolates from farms where resistance was detected, @entity1536 resistance was higher among Camp. coli (28.7%) than among Camp. @entity5363 (11.3%). PFGE typing of @entity1536 -resistant and @entity1536 -susceptible isolates from four farms indicated that certain resistant isolates belonged to specific clones that were able to persist on the farms during several rotations, even in the absence of selective pressure. Some clones were present and repeatedly isolated in both a @entity1536 -susceptible and @entity1536 -resistant variant. CONCLUSIONS: Overall, @entity1536 resistance among @entity5363 isolates from Danish broilers was 7.5% in 1998 and 1999; it was higher among Camp. coli than Camp. @entity5363 . Genetic diversity among resistant isolates was lower than among susceptible isolates, and certain clones existed in both a resistant and a susceptible variant. Some resistant clones appeared to persist on the farms and were repeatedly isolated from poultry flocks. SIGNIFICANCE AND IMPACT OF THE STUDY: The study is important for the understanding of persistence and dynamics of @entity5363 in broiler houses. It also highlights the extent, farm-to-farm variation and persistence of @entity1536 -resistant @entity5363 in broiler houses.
