title: Tiamulin resistance in porcine Brachyspira pilosicoli isolates.
abstract: There are few studies on antimicrobial susceptibility of Brachyspira pilosicoli, therefore this study was performed to investigate the situation among isolates from pigs. The tiamulin and tylosin susceptibility was determined by broth dilution for 93 and 86 porcine B. pilosicoli isolates, respectively. The isolates came from clinical samples taken in Swedish pig herds during the years 2002 and 2003. The tylosin minimal inhibitory concentration (MIC) was >16 microg/ml for 50% (n=43) of the isolates tested. A tiamulin MIC >2 microg/ml was obtained for 14% (n=13) of the isolates and these were also tested against doxycycline, salinomycin, valnemulin, lincomycin and aivlosin. For these isolates the susceptibility to salinomycin and doxycycline was high but the MICs for aivlosin varied. The relationship between the 13 tiamulin resistant isolates was analyzed by pulsed-field gel electrophoresis (PFGE). Among the 13 isolates 10 different PFGE patterns were identified.
authors.affiliation: Department of Antibiotics, National Veterinary Institute, SE-751 89 Uppsala, Sweden. marit.pringle@sva.se
authors.forename: M
authors.initials: M
authors.lastname: Pringle
authors.forename: A
authors.initials: A
authors.lastname: Landén
authors.forename: A
authors.initials: A
authors.lastname: Franklin
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004224:Diterpenes / Q000494:pharmacology; D004318:Doxycycline / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D005243:Feces; D008826:Microbial Sensitivity Tests; D011714:Pyrans / Q000494:pharmacology; D013144:Spirochaetales / Q000187:drug effects* / Q000302:isolation & purification*; D013552:Swine / Q000382:microbiology*; D013997:Time Factors; D015645:Tylosin / Q000031:analogs & derivatives / Q000494:pharmacology; D000095662:Polyether Polyketides
chemical_list: D000900:Anti-Bacterial Agents; D004224:Diterpenes; D004318:Doxycycline; D011714:Pyrans; D015645:Tylosin; C010327:salinomycin; D000095662:Polyether Polyketides; C509469:aivlosin; C014224:tiamulin