Antibiogram profile of Staphylococcus aureus isolates in subclinical bovine mastitis milk

Subclinical mastitis is a significantly important disease, causing economic losses in the livestock sector. The aim of this study was to determine the antimicrobial resistance of Staphylococcus aureus isolated from subclinical mastitis milk. A total of 402 lactating animals (242 cattle and 160 buffaloes) were screened for subclinical mastitis, out of these 96 animals (76 cattle and 20 buffaloes) were positive. A total of 96 subclinical mastitis milk samples, Staphylococcus aureus were isolated from the 27 milk samples. Overall prevalence of Staphylococcus aureus in subclinical bovine mastitis was 28.13%. The prevalence of SCM on the basis of mCMT grading was 51.04% (+), 33.33% (++) and 15.63% (+++) in bovine milk. The Staphylococcus aureus isolates showed resistance to Penicillin-G (55.56%), followed by Ciprofloxacin (25.93%), Tetracycline (18.52%), Erythromycin (18.52%) and Clindamycin (3.70%). In addition, 25.93% (Erythromycin), 7.41% (Ciprofloxacin) and 3.70% (Cefoxitin, Clindamycin and Tetracycline) of the tested Staphylococcus aureus strains exhibited intermediate sensitivity. This study confirms the importance of Staphylococcus aureus as a major mastitis causing bacterium and existence of resistance to frequently used antibiotic by Staphylococcus aureus and a potential risk for public health from nearly possible transmission of the Staphylococcus aureus strains as milk borne pathogen.