ABSTRACT

A rise in the incidence of disease in a herd results in multiplied use of antimicrobials, which in turn increases the presence of antibiotic residues in milk and increased bacterial resistance to antimicrobials. Continued use of antibiotics in the remedy and prevention of diseases of dairy cows always needs to be scrutinized. With this background, we carried out the present study to screen the major pathogens of bovine mastitis circulating in and around Meerut, Uttar Pradesh, India and their sensitivity to frequently used antibiotics. 30 milk samples suspected for mastitis based on clinical manifestations were collected and processed for bacterial isolation, identification and culture sensitivity test. Among the isolates, 14 (46.67%) were Gram-positive bacteria, 11 (36.67 %) Gram negative and 5 (16.67 %) were mixed infection. The isolated mastitis dweller bacteria were Staphylococcus spp. (46.67 %), E. coli (36.67 %), and mixed infection spp. (16.67 %). The studies of in vitro antibiogram revealed gentamicin to be the most effective drug (93.34 %), followed by enrofloxacin (66.67 %), cefotaxime+clavulanic acid (63.34 %), ampicillin+sulbactam (60.00 %), chloramphenicol (60.00 %), amoxicillin+sulbactam (53.34 %), colistin (46.67 %), ciprofloxacin (40.00 %), oxytetracycline (33.34 %), streptomycin (33.34 %), amoxicillin + clavulanic acid (13.34 %) and ampicillin/cloxacillin (10.00 %) against the bacterial isolates from mastitis milk. These findings suggest bacterial resistance against commonly used advanced drugs and combination of drugs. Thus, it can help to develop guidelines for practitioners in the choice of the most appropriate antibiotic. The outcomes of study contribute to risk assessment of anti-microbial resistance (AMR) and provide a standard baseline for setting up and assessing control measures and structuring strategies to constrain AMR.