Applied Research Note: Pulsed-field gel electrophoresis and antimicrobial resistance profiles of Campylobacter jejuni isolated from Brazilian broiler farms

We studied the on-farm variety of thermotolerant Campylobacter strains isolated from field samples received over a 12-mo period from four broiler-producing companies in southern Brazil. In total, 515 of 807 (63.8%) of analyzed samples were found to be Campylobacter-positive. Campylobacter jejuni and C. coli were detected; the first one being more frequently isolated (98.2%). The highest antimicrobial resistance levels in a subset of 80 C. jejuni strains were found against enrofloxacin (89.5%) and ciprofloxacin (83.3%). Most of the 28 DNA macrorestriction profiles identified in C. jejuni were unique to each sampled broiler company. Genetically related C. jejuni populations were detected on different broiler farms integrated to the same company on different sampling occasions. Undistinguished strains were found in the indoor environment and in broilers on the same farm. The finding of recurrent strains on integrated farms suggests that particular factors or management practices may play a role in the dispersion or carry-over of C. jejuni in the studied broiler companies.