Investigation of nasal colonization by coagulase-positive staphylococci and methicillin resistance in dogs

Abstract

This study aimed to determine the presence, rate, and species distribution of coagulase-positive staphylococci (CPS) in nasal swab samples from dogs and to investigate phenotypic and genotypic methicillin resistance. To this end, 21 (10.5%) CPS, including 7 (33.3%) S. aureus and 14 (66.6%) S. intermedius group (SIG), were isolated from nasal swab samples from 200 dogs. A total of 14 SIG members (100%) were also identified as S. pseudintermedius by multiplex polymerase chain reaction (m-PCR). Phenotypic methicillin resistance was observed in 16 (76.19%) of the 21 CPS isolated from 200 dogs from 8 different clinics and shelters. To detect genotypic methicillin resistance, the presence of the mecA and mecC genes, responsible for methicillin resistance, was detected by the multiplex polymerase chain reaction method. The mecA gene was found in 8 (38.09%) of the 21 isolates. The mecC gene was not detected in any of the samples, including isolates showing phenotypic methicillin resistance. It was found that neither the presence of CPS nor the presence of the mecA gene was statistically correlated with age, sex, or antibiotic use in the previous year (p > 0.05). Furthermore, CPS and mecA-positive isolates were evaluated according to whether they were obtained from shelters or clinics. It was concluded that the source of the isolates was not important for our study (p > 0.05). Our findings suggest that phenotypic resistance detected in epidemiological studies should be confirmed by molecular methods. At the same time, the fact that mecC gene-positive staphylococcal isolates were not detected in our study is promising for Turkey.