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In this study we focused on the antibiotic resistance profiles of livestock-associated coagulase-negative staphylococci (LA-CoNS) to assess their risk potential for horizontal gene transfer of known or novel antibiotic resistance genes into LA-MRSA. Among 400 LA-CoNS isolates from dust and manure samples in diverse animal husbandries, we identified 20 different staphylococcal species, with S. sciuri being the most abundant species (45%), followed by S. simulans (14%), S. chromogenes (10%), S. pasteuri (7%) and S. haemolyticus (6%). High resistance rates were detected for tetracycline (70%), oxacillin and penicillin (65%), fusidic acid (52%), clindamycin (55%) and erythromycin (40%), while for other antibiotics, e.g. rifampicin, vancomycin, gentamicin and quinupristin-dalfopristin, LA-CoNS showed high susceptibility. Moreover, intrinsic resistance to fusidic acid and a lower susceptibility to moxifloxacin were found among S. sciuri, which dominated the population in the livestock environment. We also tested the MIC levels of daptomycin, a last resort antibiotic in the treatment of MRSA infections, and detected an alarmingly high
tolerance to daptomycin (average MIC levels of 4 μg/ml) among LA-CoNS and S. sciuri. In particular, two S. sciuri isolates were demonstrated to exhibit high-level daptomycin resistance. Future work aims at the identification of the molecular mechanism behind the daptomycin resistance phenotype to weigh the danger of horizontal gene transfer to MRSA/VRSA.