Identification of the Genotypes of Extended-spectrum β-lactamase Producing Escherichia coli in the Small Intestine of Broiler Chickens at a Traditional Market in Surabaya, Indonesia

Escherichia coli infection from inside the chicken’s body may be present if the previously slaughtered chicken was contaminated with pathogens or the cage’s hygiene is inadequate. One of the resistance mechanisms against antibiotics used by Gram-negative bacteria of the Enterobacteriaceae family is the production of extended-spectrum β-lactamases (ESBL). Research is required to determine which E. coli genotypes in broiler chicken samples collected from Surabaya’s traditional marketplaces produce ESBL.

A total of 100 small intestine samples collected from broiler chickens were used in this study. After initial processing all the samples were separately injected into Eosin Methylene Blue Agar (EMBA) and Indole, Methyl Red, Voges Proskauer and Citrate (IMViC) tests were used to confirm the results. A test for antibiotic sensitivity based on the Kirby-Bauer method called the Double Disk Synergy Test (DDST) was used to analyze isolates that showed resistance to aztreonam and multidrug resistance (MDR). PCR testing was performed on ESBL-verified isolates to detect the TEM and CTX-M genes.

The results of the test for E. coli antibiotic resistance revealed that 14 isolates were proven to be multidrug-resistant (MDR) and six of them were found to be E. coli that produced ESBL. Four isolates were found to carry the TEM and CTX-M genes after genotyping analysis. Understanding the dangers of using antibiotics as feed additives and growth promoters is crucial for farmers to address the problem of ESBL-producing E. coli bacteria in chickens. Furthermore, the government needs to take action to monitor and enforce stronger controls on the use of antibiotics, which are even readily available on the market.