Incidence and pattern of antibiotic resistance of Staphylococcus aureus isolated from clinical and subclinical mastitis in cattle and buffaloes

Abstract

The main objective of the present study was to report the prevalence of methicillin resistant Staphylococcus aureus (MRSA) among bovines used for milk production in Mathura, India. A total of 80 milk samples were collected from clinical and subclinical cases of mastitis from cows (40) and buffalos (40). Milk samples were processed for isolation and identification of S. aureus using standard bacteriological procedures. Staphylococcus aureus were isolated from only 27 samples showing the overall incidence of Staphylococcus aureus in clinical as well as sub clinical mastitis was 33.75%. The incidence of Staphylococcus aureus was higher (50.00%) in clinical mastitis in comparison to that of subclinical mastitis (17.50%). The results revealed that the incidence of Staphylococcus aureus in clinical as well as sub-clinical mastitis was higher in cattle in comparison to buffaloes. Drug sensitivity revealed the 100% resistance against penicillins followed by vancomycin (88.89%), nalidixic acid (77.78%), cefixime, methicillin, novobiocin (66.67% each), amoxiclav, colistin, pipemidic acid (55.56% each), ofloxacin, streptomycin, sulphamethizole (44.44% each), ampicillin/sulbactam, cefalexin, cefazolin, cefoperazone, enrofloxacin, floxidin, meropenem (33.33% each), cefuroxim, ciprofloxacin, clindamycin, gentamicin, levofloxacin, norfloxacin, tetracycline (22.22% each). Eighteen isolates were found to be methicillin-resistant, while the remaining (09) were methicillin-susceptible. Similarly, twenty four S. aureus isolates were intermediate to vancomycin while three were vancomycin susceptible and no isolate was resistant to vancomycin. Thus, the findings are useful for formulating specific control programs for bovine mastitis caused by S. aureus in this region.