Resistance to Antibiotics and the Occurrence of Genes Responsible for the Development of Methicillin Resistance in ce:italic>Staphylococcus/ce:italic> Bacteria Isolated From the Environment of Horse Riding Centers

摘要

The purpose of the study was to identify species, to determine the drug resistance profile, and to evaluate the occurrence of genes responsible for the development of methicillin resistance inStaphylococcusbacteria isolated from the environment of horse riding centers. Staphylococci were isolated from air, manure, and nostrils of horses located in three horse riding centers, differing in horse stabling system—box stall stabling (OJK Pegaz and KJK Szary) and free-range stabling (SKH Nielepice). The dominant species wasStaphylococcus vitulinus. A large variation in the frequency of occurrence of individual species between horse riding centers was determined. Resistance to antibiotics was determined by means of disc diffusion method and polymerase chain reaction technique to detectmecAgenes responsible for methicillin resistance. In total, 408 strains were collected, most from SKH Nielepice, and least from OJK Pegaz. The highest resistance was found to gentamicin and tetracycline. Multidrug-resistant isolates were also detected in KJK Szary (10), in SKH Nielepice (5), and in OJK Pegaz (4). Methicillin resistance determined by disk diffusion assay was found in 23 strains, while themecAgene was detected in 142 isolates. A total of 137 strains holding themecAgene are coagulase-negative staphylococci (CNS), which, as shown by our own studies, may be a reservoir of methicillin resistance. Most commonly, themecAgene was found in staphylococci isolated in KJK Szary (61.70%). ThemecAgene was detected in five strains that belonged toStaphylococcus aureusspecies and came from horses in SKH Nielepice, indicating the presence of methicillin-resistantStaphylococcus aureusstrains in these animals.