title: Phenotypic and genotypic anti-microbial resistance profiles of campylobacters from untreated feedlot cattle and their environment.
abstract: Anti-microbial resistance is an emerging public health issue. Farmed animals may act as reservoirs and potential sources of anti-microbial resistant Campylobacters. The aim of this study was to investigate the anti-microbial resistance profile of cattle and environmental Campylobacter isolates from normal untreated feedlot cattle, the role of the gyrA Thr-86-Ile mutation in ciprofloxacin-resistant Campylobacter jejuni isolates and the involvement of the tripartite CmeABC efflux system for multi-resistant C. jejuni isolates. The phenotypic anti-microbial resistance testing was carried out on 500 Campylobacter isolates (445 cattle isolates and 55 environmental isolates). In general, there was a higher level of anti-microbial resistance for the environmental isolates compared with the animal isolates, 45% of the animal isolates were resistant to one or more of the seven anti-microbials compared with 84% of the environmental isolates. The combined cattle and environmental Campylobacters had 34 (6.8%) isolates resistant to three or more of the seven anti-microbials tested on all isolates and 11 (2.2%) isolates were resistant to the seven anti-microbials. There was a substantial level of ciprofloxacin-resistant Campylobacters in both animal (8.5%) and environmental (21.8%) isolates. The gyrA Thr-86-Ile mutation was only present in five of 22 ciprofloxacin-resistant C. jejuni isolates investigated. No multi-drug-resistant associated mutation was detected in the CmeB or the CmeR regions investigated. In conclusion, our study observed a substantial level of Campylobacter anti-microbial resistance, highlighting the need for an active anti-microbial surveillance program for food animals in Ireland and the importance of the chosen sampling point can have on the findings of such a program.
authors.affiliation: Department of Agriculture and Food, Central Veterinary Research Laboratory, Abbotstown, Castleknock, Dublin 15, Ireland.
authors.forename: D
authors.initials: D
authors.lastname: Minihan
authors.forename: P
authors.initials: P
authors.lastname: Whyte
authors.forename: M
authors.initials: M
authors.lastname: O'mahony
authors.forename: D
authors.initials: D
authors.lastname: Cowley
authors.forename: F
authors.initials: F
authors.lastname: O'halloran
authors.forename: D
authors.initials: D
authors.lastname: Corcoran
authors.forename: S
authors.initials: S
authors.lastname: Fanning
authors.forename: J D
authors.initials: JD
authors.lastname: Collins
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002167:Campylobacter / Q000145:classification* / Q000187:drug effects* / Q000235:genetics; D002169:Campylobacter Infections / Q000188:drug therapy / Q000382:microbiology / Q000662:veterinary*; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy* / Q000382:microbiology; D002939:Ciprofloxacin / Q000627:therapeutic use; D003257:Consumer Product Safety; D024881:Drug Resistance, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D004783:Environmental Microbiology; D005838:Genotype; D007494:Ireland; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D009154:Mutation; D010641:Phenotype; D010802:Phylogeny; D011634:Public Health
chemical_list: D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin