title: Comparative quantification of the in vitro activity of veterinary fluoroquinolones.
abstract: The aim of this study was to compare the in vitro antimicrobial activity of the veterinary fluoroquinolones against a panel of recently isolated porcine and bovine bacterial pathogens. The study used enrofloxacin as a benchmark against which other agents were compared, being the most common fluoroquinolone used in treatment of bovine and porcine infections. The activity of ciprofloxacin was also assessed as it is the main metabolite of enrofloxacin in cattle. Enrofloxacin and ciprofloxacin generally showed higher antibacterial activity, in terms of MIC(50) values, for most pathogen species when compared with marbofloxacin, difloxacin, danofloxacin and norfloxacin. Ciprofloxacin showed significantly greater in vitro antibacterial activity than enrofloxacin against M. haemolytica, P. multocida and E. coli, whereas enrofloxacin showed greater activity than ciprofloxacin against S. aureus. Marbofloxacin was significantly more active than enrofloxacin against M. haemolytica, E. coli and B. bronchiseptica but less active against P. multocida, S. aureus, coagulase negative Staphylococci, S. dysgalactiae, S. uberis, A. pleuropneumoniae and S. suis. Danofloxacin was significantly less active than enrofloxacin against P. multocida, E. coli, S. uberis, A. pleuropneumoniae and S. suis. Enrofloxacin and its metabolite ciprofloxacin showed the highest in vitro activities against most bovine pathogens tested and the porcine pathogens also showed a high degree of sensitivity to enrofloxacin. These data facilitate further pharmacokinetic/pharmacodynamic comparison of fluoroquinolones currently used in veterinary medicine.
authors.affiliation: Institute of Microbiology and Epizootics, Free University Berlin, Philippstrasse 13, 10115 Berlin, Germany. grobbel.mirjam@vetmed.fu-berlin.de
authors.forename: M
authors.initials: M
authors.lastname: Grobbel
authors.forename: A
authors.initials: A
authors.lastname: Lübke-Becker
authors.forename: L H
authors.initials: LH
authors.lastname: Wieler
authors.forename: R
authors.initials: R
authors.lastname: Froyman
authors.forename: S
authors.initials: S
authors.lastname: Friederichs
authors.forename: S
authors.initials: S
authors.lastname: Filios
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology / Q000662:veterinary; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy / Q000382:microbiology; D002939:Ciprofloxacin / Q000494:pharmacology; D015169:Colony Count, Microbial / Q000662:veterinary; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D000077422:Enrofloxacin; D024841:Fluoroquinolones / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000662:veterinary*; D013552:Swine; D013553:Swine Diseases / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D000077422:Enrofloxacin; D002939:Ciprofloxacin