MOLECULAR CHARACTERIZATION OF MULTI DRUG RESISTANT ESCHERICHIA COLI CAUSING BOVINE MASTITIS

Different antibiotics are used to treat mastitis in dairy cows that is caused by Escherichia coli (E. coli). Addressing this threat requires a combination of a multidisciplinary approach involving human, animal, and environmental health. Because antibiotic agents used in veterinary medication may be the same or similar to those in human medication. Mastitis is a common and economically important disease in dairy cattle. It remains one of the most common reasons for the extensive use of antimicrobials in dairy farms, leading to the emergence of antimicrobial-resistant pathogens. The current study aimed to investigate the incidence of multidrug-resistant E. coli in dairy milk samples collected from Mastitis and healthy milk in the district of Dir Lower, characterize the multi-drug-resistant (MDR) E. coli, and molecular detection of the predominant ESBL-encoding genes by using PCR assay. All confirmed (17) samples of ESBL-encoding E. coli strains were tested via conventional PCR for the molecular screening of blaCTX-M gene, blaTEM gene, and blaSHV gene from mastitic milk isolates. Out of 17 isolates, 6 (35.29%) isolates were positive for co-existence of blaCTX-M gene and blaTEM gene, 5 (29.41%) isolates were positive for single existence of blaCTX-M, 2 (11.76%) isolates were positive for single existence of blaTEM, 4 (23.52%) isolates were positive for blaSHV gene. In this study, the most predominant gene was blaCTX-M gene, showing (64.70%) followed by blaTEM gene (47.05%) and blaSHV gene (23.52%). Eleven different antibiotics were used in this study to check their susceptibility pattern. The isolated strains were highly resistant to Ampicillin (100 %) and highly sensitive to Levofloxacin (100%), Ciprofloxacin (100%), and Chloramphenicol (100%). The incidence of these genes in indicator organisms from milk samples, enforced the potential of food-producing animals as sources of MDR organism’s infection in humans via the food chain. Thus, there is a need for the adoption of a tripartite One Health approach in surveillance to control antimicrobial resistance, and antibiotic sensitivity must be checked before treatment of any infection.