title: Antimicrobial susceptibility of mastitis pathogens of dairy cows in Switzerland.
abstract: This study evaluates the antimicrobial resistance of pathogens cultured from 3'954 quarter milk samples from dairy cows in Switzerland. A total of 1'228 Streptococcus (Strep.) uberis, 1'107 Staphylococcus (Staph.) spp. other than Staph. aureus, 598 coliform, 490 Staph. aureus, 270 Enterococcus spp. and 213 Strep. dysgalactiae isolates were tested for susceptibility to 9 antimicrobial drugs using agar diffusion. Streptococcus uberis, Strep. dysgalactiae and Staph. aureus had the highest antimicrobial sensitivities to amoxicillin clavulanic acid (99.6 %, 100 % and 98.8 %, respectively). Of all isolated pathogens, only 2.6 % were resistant to amoxicillin clavulanic acid and 8.0 % to cefoperazone. The overall resistance level to gentamicin was 45.5 %, to penicillin 39.2 %, and to ampicillin 26.7 %. The highest resistance levels occurred with polymyxin (86.0 %), oxacillin (64.7 %) and lincomycin (53.7 %). Our results showed that at least one resistance exists to one antimicrobial agent examined in this study. Ideally the selection of the antibacterial drug for the treatment of intramammary infection should be based on antibiotic susceptibility testing.
authors.affiliation: Department of Farm animals, Vetsuisse Faculty University of Zurich.
authors.forename: F
authors.initials: F
authors.lastname: Rüegsegger
authors.affiliation: Department of Farm animals, Vetsuisse Faculty University of Zurich.
authors.forename: J
authors.initials: J
authors.lastname: Ruf
authors.affiliation: Zoetis GmbH, Zurich.
authors.forename: A
authors.initials: A
authors.lastname: Tschuor
authors.affiliation: Idexx Diavet Laboratories, Bäch, Switzerland.
authors.forename: Y
authors.initials: Y
authors.lastname: Sigrist
authors.affiliation: Idexx Diavet Laboratories, Bäch, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Rosskopf
authors.affiliation: Department of Farm animals, Vetsuisse Faculty University of Zurich.
authors.forename: M
authors.initials: M
authors.lastname: Hässig
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002417:Cattle; D024881:Drug Resistance, Bacterial; D005260:Female; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology / Q000662:veterinary*; D008414:Mastitis, Bovine / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D013557:Switzerland
chemical_list: D000900:Anti-Bacterial Agents
keywords: Agardiffusion; Antibiotikaresistenz; Mastitis; Rind; Schweiz; Switzerland; agar diffusion; antimicrobial resistance; cattle; mastitis