Asian Journal of Microbiology and Biotechnology

Antimicrobial resistance (AMR) is a global health concern affecting both human and veterinary sectors. Overuse and misuse of antibiotics is accelerating the problem of antimicrobial resistance in the pathogens causing infectious diseases. Mastitis is the painful inflammation of mammary gland and is considered as common infection of dairy cattle. Several studies emphasized that the bacterial pathogens associated with bovine mastitis are multidrug resistant. Hence, the present study is carried out to determine prevalence and antimicrobial resistance patterns of bacterial pathogens causing bovine mastitis. A total of 120 mastitic milk samples were collected and the prevalence rates were analyzed according to breed, age, parity and lactation stages. The identification of bacterial strains was performed based on cultural characteristics on specific media, biochemical tests and molecular identification using specific primers. Antibiotic susceptibility testing of the isolates was done by Kirby-Bauer disk diffusion test. Results indicated the presence of Staphylococcus aureus, Escherichia coli, Klebsiella, and Salmonella spp. at prevalence rates of 19.53%, 10%, 2.5%, and 5.8% respectively. Determination of the AMR profile revealed the resistance of all pathogens towards ampicillin. S. aureus is predominantly resistant to penicillin (100%), followed by methicillin (94.74%), and ampicillin (89.47%), E. coli to ampicillin (96.6%), amoxicillin and ciprofloxacin (83.33% each), Klebsiella to ampicillin and amoxicillin (100%) whereas Salmonella spp. to ampicillin (100%) and amoxicillin (85.71%). The findings of the study suggested the high prevalence of multidrug resistant pathogens causing mastitis, increasing the risk of reduced antimicrobial efficacy and affecting the public health.