{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T01:07:24Z","timestamp":1788570444305,"version":"build-2803163510"},"reference-count":52,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,16]],"date-time":"2021-12-16T00:00:00Z","timestamp":1639612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (Formas)","award":["2016-01143"],"award-info":[{"award-number":["2016-01143"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Antibiotic resistance is a major challenge worldwide and increased resistance to quinolones in Campylobacter is being reported. Analysis of antibiotic resistance was performed on 157 Campylobacter strains (123 C. jejuni and 34 C. coli) from conventional and organic chickens produced in Sweden. Susceptibility for tetracycline, ciprofloxacin, erythromycin, nalidixic acid, streptomycin, and gentamycin was determined by microdilution. All 77 isolates from organic chickens were sensitive to all antibiotics, except two C. jejuni that were resistant to tetracycline. Of the 80 isolates from conventional chickens, 22.5% of C. jejuni and 11.1% of C. coli were resistant to quinolones and 5.6% of C. jejuni were resistant to tetracycline. Whole-genome sequencing resulted in 50 different sequence types of C. jejuni and six of C. coli. Nine sequence types were found in both organic and conventional chickens. Two of these (ST-19 and ST-257) included isolates from conventional broilers with different resistance phenotypes to the remaining isolates from conventional and organic broilers. There are management differences between the production systems, such as feed, breed, use of coccidiostats, and access to outdoor area. It is unlikely that quinolone resistance has arisen due to use of antimicrobials, since fluoroquinolones are not permitted in Swedish broiler production.<\/jats:p>","DOI":"10.3390\/pathogens10121630","type":"journal-article","created":{"date-parts":[[2021,12,16]],"date-time":"2021-12-16T21:32:40Z","timestamp":1639690360000},"page":"1630","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Differences in Genotype and Antimicrobial Resistance between Campylobacter spp. Isolated from Organic and Conventionally Produced Chickens in Sweden"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3764-2341","authenticated-orcid":false,"given":"Ingrid","family":"Hansson","sequence":"first","affiliation":[{"name":"Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrik","family":"Ellstr\u00f6m","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences, Uppsala University, SE-751 85 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oskar","family":"Nilsson","sequence":"additional","affiliation":[{"name":"Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute (SVA), SE-751 89 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matilda","family":"Chaba","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moa","family":"Skarin","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lise-Lotte","family":"Fernstr\u00f6m","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4080-5183","authenticated-orcid":false,"given":"Sara","family":"Frosth","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7036, SE-750 07 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,16]]},"reference":[{"key":"ref_1","unstructured":"NNDSS, Annual Report Working Group (2016). Australia\u2019s notifiable disease status, 2014: Annual report of the National Notifiable Diseases Surveillance System. Commun. Dis. Intell., 40, E48\u2013E145."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1624","DOI":"10.1093\/cid\/cix624","article-title":"Increasing Campylobacter Infections, Outbreaks, and Antimicrobial Resistance in the United States, 2004\u20132012","volume":"65","author":"Geissler","year":"2017","journal-title":"Clin. Infect. Dis."},{"key":"ref_3","unstructured":"The Institute of Environmental Science and Research Ltd. (ESR) (2021, June 28). Notifiable Diseases in New Zealand; Annual Report. Available online: www.surv.esr.cri.nz."},{"key":"#cr-split#-ref_4.1","unstructured":"(2021). 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