TY - JOUR T1 - Characterization of methicillin-resistant non-Staphylococcus aureus staphylococci carriage isolates from different bovine populations. JF - J Antimicrob Chemother Y1 - 2013 A1 - Vanderhaeghen, Wannes A1 - Vandendriessche, Stien A1 - Florence Crombé A1 - Nemeghaire, Stéphanie A1 - Marc Dispas A1 - Denis, Olivier A1 - Hermans, Katleen A1 - Haesebrouck, Freddy A1 - Butaye, Patrick KW - Animals KW - Carrier State KW - Cattle KW - DNA, Bacterial KW - Genotype KW - Methicillin Resistance KW - Microbial Sensitivity Tests KW - Molecular Typing KW - Nasal Mucosa KW - Phylogeography KW - polymerase chain reaction KW - Staphylococcal Infections KW - staphylococcus AB -

OBJECTIVES: This study aimed at investigating bovine non-Staphylococcus aureus staphylococci for their role as a potential reservoir for methicillin resistance.

METHODS: Nasal swab samples were collected from 150 veal calves on 15 veal farms, 100 dairy cows on 10 dairy farms and 100 beef cows on 10 beef farms. Suspected staphylococcal isolates were investigated by PCR for the presence of the classic mecA and mecA(LGA251). Methicillin-resistant non-S. aureus staphylococci (MRNAS) were genotypically identified and were characterized by broth microdilution antimicrobial susceptibility testing and staphylococcal cassette chromosome mec (SCCmec) typing.

RESULTS: The MRNAS (n = 101) carriage rate was estimated as 30.29% (95% CI 6.14%-74.28%) in veal calves, 13.1% (95% CI 1.28%-63.72%) in dairy cows and 24.8% (95% CI 11.97%-44.42%) in beef cows. Carriage rates were not significantly different between the three populations (P > 0.05). mecA(LGA251) was not detected. Most (n = 80) MRNAS were identified as Staphylococcus sciuri, Staphylococcus lentus or Staphylococcus fleurettii. Resistance to aminoglycosides, macrolide-lincosamide-streptogramin antimicrobials, tetracycline and ciprofloxacin was frequently detected. Two linezolid-resistant MRNAS from veal calves carried the multidrug-resistance gene cfr. SCCmec cassettes of type III predominated (n = 46); another 40 SCCmec cassettes harboured a class A mec complex without identifiable ccr complex; type IVa, type V and several other non-typeable cassettes were detected in low frequencies, especially in methicillin-resistant Staphylococcus epidermidis.

CONCLUSIONS: The SCCmec types predominating in bovine MRNAS differ from those mostly detected in livestock-associated methicillin-resistant S. aureus strains. Yet, the detection of cfr and the high level of other antimicrobial resistances suggest a potentially important role of bovine MRNAS as a reservoir for resistance determinants other than SCCmec.

VL - 68 CP - 2 U1 - http://www.ncbi.nlm.nih.gov/pubmed/23090977?dopt=Abstract M3 - 10.1093/jac/dks403 ER -