Antimicrobial resistance of Campylobacter spp. isolated from broiler flocks in Iceland 2001-2005.
Minimum inhibitory concentrations of six antimicrobial agents were determined for one Campylobacter sp. isolate from each of the 362 Campylobacter-positive commercial chicken flocks in Iceland in the years 2001-2005. Of all isolates tested, 6.9% were resistant, although none were multiresistant. Resistance to ampicillin was most commonly observed (3.6%) followed by resistance to enrofloxacin (3%), nalidixic acid (1.9%), and oxytetracyclin (0.3%), with cross-resistance between enrofloxacin and nalidixic acid. All isolates were susceptible to erythromycin and gentamicin. Resistance rates among Campylobacter coli isolates (7/13 or 53.8%) were much higher than among Campylobacter jejuni isolates (18/349 or 5.2%), and resistance patterns differed. Resistant strains were compared using pulsed field gel electrophoresis. Macrorestriction with SmaI and KpnI restriction enzymes yielded 13 different pulsotypes, none of which indicated a predominant genotype. Specific pulsotypes with uniform resistance patterns arising on geographically separated farms indicate clonal dissemination. Although resistance levels were low and similar to that seen in the other Nordic countries, further research on this matter is needed as there is no antimicrobial selective pressure in chicken farming in Iceland.
Thorsteinsdottir
Thorunn R
TR
Institute for Experimental Pathology, University of Iceland, Reykjavik, Iceland. thoruth@hi.is
Kristinsson
Karl G
KG
Fridriksdottir
Vala
V
Gunnarsson
Eggert
E
D000822:Animal Husbandry; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002167:Campylobacter / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D002645:Chickens / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D007494:Ireland; D008826:Microbial Sensitivity Tests
D000900:Anti-Bacterial Agents