ISOLATION AND ANTIBIOGRAM OF BETA HAEMOLYTIC STAPHYLOCOCCUS AUREUS ASSOCIATED WITH BOVINE CLINICAL MASTITIS

The present study was conducted to detect beta haemolytic Staphylococcus aureus associated with clinical mastitis in bovines. A total of 112 milk samples were collected from all the four quarters of each of 28 animals (13 cattle and 15 buffaloes) suffering from clinical mastitis. Forty milk samples originating from these animals showed the presence of Staphylococci. Isolates were confirmed to be S. aureus by a combination of various tests i.e., catalase, coagulase and growth on mannitol salt agar plate. Beta haemolytic activity of 10 field isolates was determined by ‘Hot-Cold’ lysis on 5% sheep blood agar plate and titres in culture supernatant of these isolates were determined by microtitre plate method. Beta haemolytic titres ranged from 16 to 256 indicating significant variation in the ability of these isolates to produce toxin. All the isolates were found sensitive to methicillin, chloramphenicol and ampicillin/sulbactam.