Antibiogram of Staphylococcus aureus isolated from clinical cases of bovine mastitis

Abstract

The present study was conducted to determine the antibiogram of Staphyloccus aureus isolates obtained from clinical cases of bovine mastitis. A total of 102 S. aureus isolated from mastitic milk samples were subjected to In vitro antibiotic sensitivity testing against 14 different antibiotics belonging to 9 different classes. The antibiotics comprised of mixture of conventionally and few non-conventionally used antibiotics. Diameters of zone of inhibitions were recorded and interpreted according to the breakpoints given by CLSI. On the basis of sensitivity pattern, isolates were categorized into multidrug-resistant (MDR), extreme drugresistant (XDR), and pandrug-resistant (PDR). Variable sensitivity with a wide range was observed against antibiotics. Antibiotic sensitivity pattern revealed maximum sensitivity towards chloramphenicol (88.24%) and maximum resistance towards vancomycin (91.18%). Out of 102 isolates, 73 (71.56%) isolates were
found to be multidrug-resistant. None of the multidrug isolates were found to be extreme drug-resistant and pan drug-resistant. No relation was observed between sensitivity pattern with conventional and non conventional antibiotics.