title: Antimicrobial resistance in Campylobacter spp. isolated from Ontario sheep flocks and associations between antimicrobial use and antimicrobial resistance.
abstract: The objectives of this study were to determine the prevalence of antimicrobial resistance (AMR) in faecal Campylobacter spp. from lambs and adult sheep and associations between antimicrobial use (AMU) and AMR. A total of 275 faecal samples collected during initial and final visits from 51 sheep flocks, including one feedlot, across southern Ontario were tested for the presence of Campylobacter spp. Campylobacter jejuni was detected in 52% (143/275) of the faecal samples, Campylobacter coli in 7% (19/275), Campylobacter lari in 1% (2/275) and 2% (4/275) were non-speciated Campylobacter. Broth microdilution was used to test antimicrobial susceptibility of 162 isolates to nine antimicrobials. Campylobacter jejuni isolates (n = 142) were resistant to tetracycline (39%), ciprofloxacin (4%), nalidixic acid (4%) and telithromycin (1%). C. coli isolates (n = 19) were resistant to tetracycline (74%), and azithromycin, clindamycin, erythromycin, and telithromycin (5%). The C. lari isolate displayed resistance to nalidixic acid. No statistically significant associations were found between AMU and AMR during multivariate modelling in this study.
authors.affiliation: Department of Population Medicine, University of Guelph, Guelph, ON, Canada. lscott@uoguelph.ca
authors.forename: L
authors.initials: L
authors.lastname: Scott
authors.forename: P
authors.initials: P
authors.lastname: Menzies
authors.forename: R J
authors.initials: RJ
authors.lastname: Reid-Smith
authors.forename: B P
authors.initials: BP
authors.lastname: Avery
authors.forename: S A
authors.initials: SA
authors.lastname: McEwen
authors.forename: C S
authors.initials: CS
authors.lastname: Moon
authors.forename: O
authors.initials: O
authors.lastname: Berke
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002167:Campylobacter / Q000187:drug effects* / Q000302:isolation & purification; D002169:Campylobacter Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D017000:Campylobacter coli / Q000187:drug effects / Q000302:isolation & purification; D016123:Campylobacter jejuni / Q000187:drug effects / Q000302:isolation & purification; D004305:Dose-Response Relationship, Drug; D024901:Drug Resistance, Multiple, Bacterial; D005243:Feces / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D009864:Ontario / Q000453:epidemiology; D015995:Prevalence; D034561:Sheep, Domestic; D011795:Surveys and Questionnaires
chemical_list: D000900:Anti-Bacterial Agents