Mastitis is a common global and economic dairy infection in cattle causing significant financial losses and responsible for inferior milk quality and increase the treatment costs as well as act as source for new intermammary infection. Staphylococcus aureus is recognized as a problematic bacteria affecting dairy herds. This study spot highlight on the antibiogram pattern with molecular characterization of virulence genes (coa and spa) of methicillin resistant S. aureus (MRSA) from clinical mastitic cases. From examined 400 cows of small holders 120 (30%) showed clinical mastitis and S. aureus prevalence rate was 46.5%. Higher resistance to Penicillin, Chloramphenicol, Oxacillin, Tetracycline and Erythromycin were showed in antibiogram testing, while high sensitivity to Gentamycin, Vancomycin, Amoxicillin/ clavunate acid and Ciprofloxacin were observed. Moreover, out of 46 S. aureus isolates, 31(67.39%) identified as MRSA strains of highly resistance to different antimicrobials classes. The PCR model was sensitive and rapid in identification of coa and spa genes in all examined strains at 630 and 229 bp respectively. In conclusion, S. aureus represented a common pathogen causing mastitis and exhibit resistant to different antibiotics groups, in addition to it carried virulence factors such as coa and spa which play a valuable effect in the disease severity.
antibiogram, S.aureus, mastitis , PCR, coa, spa