The present study was undertaken for isolation and molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) from nasal swabs of apparently healthy cattle, buffaloes and their handlers. Out of 513 nasal swab samples analyzed, 162 (31.6%) S. aureus isolates were recovered, of which 104 (20.2%) were found positive for coagulase enzyme production. On MeReSa HICHROM agar supplemented with cefoxitin, bluish green colonies were observed in 100% coagulase positive S. aureus isolates of livestock handlers followed by buffaloes (48.6%) and cattle (24%). Disc diffusion test showed resistance to both oxacillin and cefoxitin in 7 (77.7%), 16 (43.7%) and 20 (33.3%) coagulase positive isolates of livestock handlers, buffaloes and cattle, respectively. Both mecA and blaZ genes were detected in 3 (33.3%), 10 (28.6%) and 11 (18.6%) coagulase positive isolates of livestock handlers, buffaloes and cattle, respectively. Correlation between phenotypic resistance to oxacillin, cefoxitin and presence of mecA gene was not observed.
Key words: MRSA, Coagulase, PCR, mecA, blaZ