Sub-clinical Mastitis in Murrah Buffaloes with Special Reference to Prevalence, Etiology and Antibiogram

This study was carried out to determine the prevalence of sub-clinical mastitis, its etiological agents and their antibiogram in Murrah buffaloes at an organized farm. A total of 326 quarter milk samples were screened from 82 apparently healthy buffaloes. The percent prevalence of sub-clinical mastitis was found to be lower on the basis of SCC (>5x105/ml) alone (23.17) as compared to cultural examination (29.26). However, the quarter-wise percent prevalence on the basis of SCC (11.04) was similar to bacteriological examination (11.65). On the basis of International Dairy Federation criteria, 7.05% of the quarters (SCC above 500,000/ml of milk and culturally positive), 4.60% quarters (SCC below 500,000/ml of milk but culturally positive) and 3.98% (culturally negative and SCC above 500,000/ml) were found to suffer from sub-clinical, latent and non-specifi c mastitis, respectively. Out of 38 culturally positive quarters, a total of 44 organisms were recovered. Of these, 15.90% were coagulase positive staphylococci and 47.72% were coagulase negative staphylococci followed by Streptococcus dysgalactiae 25%, Streptococcus agalactiae 9.09% and Streptococcus uberis 2.27%. and 13.63% of the quarters revealed mixed infections with Staphylococcus spp. + Streptococcus spp. Among Staphylococci, Staphylococcus aureus and Staphylococcus haemolyticus were the main isolates followed by Staphylococcus epidermidis, Staphylococcus simulans, Staphylococcus hyicus, Staphylococcus pasteuri, Staphylococcus saprophyticus subsp. saprophyticus, Staphylococcus arlettae and Staphylococcus gallinarum. All the strains of staphylococci and streptococci were found sensitive to cloxacillin, ceftriaxone and cefoperazone. Streptococci revealed 100 percent sensitivity towards penicillin, enrofl oxacin, ciprofl oxacin, lincomycin and cephalexin.