Antimicrobial resistance characteristics of Extended Spectrum Beta Lactamase (ESBL)- producing Escherichia coli from dairy farms in the Sleman district of Yogyakarta province, Indonesia

Extended Spectrum Beta Lactamase (ESBL)-producing Escherichia coli (E. coli) infections are a global health challenge
resulting from human contact with infected animals and contaminated farm environments. This study aims to identify
antimicrobial resistance patterns of ESBL-producing E. coli isolated from dairy farms in the Sleman District of Yogyakarta
Province, Indonesia. Ninety-three dairy farms with a history of antibiotic use in the previous 6 months were identified.
Samples were collected from 6 different sources (feces, milk, wastewater, animal drinking water, feed and rinses of workers’
hands) on each farm during August through November 2020. These samples were cultured with conventional microbiological
methods for the isolation of ESBL-producing E. coli. ESBL-producing E. coli was identified in one or more of the sources
in 54% (50/93) of the dairy farms sampled. Fecal samples were the most commonly positive (25%) while wastewater, animal
drinking water, feed, milk and hand rinses were positive at 16%, 10%, 5%, 4% and 3% respectively. Colonies from each
positive sample were screened for antibiotic susceptibility test using the Vitek-2 system. Resistance to trimethoprim/
sulfamethoxazole, tetracycline and gentamicin were found in 74%, 63% and 48% of the isolates, respectively. Multidrug
resistant (MDR) was identified in 50% (63/127) of the isolates. In conclusion, ESBL-producing E. coli appears widespread in dairy farms using antibiotics and antimicrobial resistance among these bacteria is common in this study area. Further study of the risk of human transmission from contaminated cattle and their environments could benefit the national antimicrobial resistance strategic plans.