Genotypic characterization of coagulase negative staphylococcus species from bovinemilk found on properties and municipalities of northern minas gerais

One hundred eleven Gram positive cocci from six dairy farms at north of Minas Gerais were identified by the proteomic technique. Staphylococcus coagulase negative (SCN) species were submitted to the disc diffusion test with conventional beta-lactam antibiotics. Strains resistant to meropenem were screened for the blaOXA-23 and blaKPC genes by PCR. Staphylococcus coagulase-negative species were evaluated by Chi-square test for resistance and multidrug resistance index. For MALDI-TOF MS the most common genus with 56.8% was Staphylococcus spp, the SCN group had a frequency of 27%. The species S. epidermidis and S. chromogenes had a higher prevalence in the herds with 35.8%, respectively. In Janaúba Nova Prima property, the mean value of the multiresistance index found was 0.6, the other properties and municipalities were 0.5. Cefoxitin (100%), oxacillin (100%), meropenem (100%) and vancomycin (100%) were the antimicrobial resistance in the herds of dairy cattle. The blaOXA-23 and blaKPC resistance genes weren’t screened in the species S. epidermidis, S. chromogenes, S. auriculares and S. haemolyticus. Other mechanisms of resistance are present in the strains causing inefficiency in the antimicrobial treatment in the herds, compromising the well-being of the animals and public health.