Antimicrobial resistance profiling of selected E. coli isolates and detection of ESBL/pAmpC-encoding genes in broiler flocks in Bosnia and Herzegovina using real-time PCR

Koro-Spahić, Amira (author), Hadžiabdić, Sead (author), Goletić, Teufik (author), Alić, Amer (author), Kustura, Aida (author), Softić, Adis (author), Residbegović, Emina (author)

Antimicrobial resistance (AMR) is a growing global issue, driven by the nontargeted use of antimicrobials in livestock. Poultry, particularly broilers, may serve as significant reservoirs for resistant Escherichia (E.) coli strains. This study aimed to isolate E. coli from broiler flocks and evaluate their in vitro susceptibility towards β-lactams, cephalosporins, carbapenems, tetracyclines, and fluoroquinolones. Additionally, a multiplex real-time PCR assay was used to detect extended-spectrum β-lactamase (ESBL)- and carbapenemase-encoding genes. A total of 48 commensal E. coli isolates from broiler flocks in Bosnia and Herzegovina (BiH) were analyzed. Phenotypic resistance, determined using the disc diffusion method, was observed for ampicillin (87.5%), amoxicillin/clavulanic acid (62.5%), cefepime (41.7%), cefoxitin (45.8%), cefotaxime (50.0%), ceftazidime (47.9%), azithromycin (58.3%), ciprofloxacin (66.7%), and tetracycline (72.9%). PCR analysis confirmed blaTEM, blaCTX-M and blaCMY genes in 24 isolates (50%), whereas blaSHV and carbapenemase-encoding genes (blaKPC, blaNDM, blaOXA-48, blaVIM and blaGES) were not detected. The high prevalence of multidrug-resistant E. coli strains highlights the need for enhanced antimicrobial stewardship in poultry production. Reducing antibiotic use, promoting alternative disease control measures, and implementing systematic resistance monitoring programs are crucial to reduce AMR in broiler farms and potential spill over to public health.

• Language: English
• Keywords: antimicrobial resistance, E. coli, broilers, Bosnia and Herzegovina
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: VF - Veterinary Faculty
• Publication status: Published
• Publication version: Version of Record
• Publication date: 01.01.2025
• Year: 2025
• Number of pages: Str. 259-268
• Numbering: Vol. 62, iss. 4
• PID: 20.500.12556/RUL-185530
• UDC: 579.842:615.33:636.5(497.6)
• ISSN on article: 2385-8761
• DOI: 10.26873/SVR-1630-2025
• COBISS.SI-ID: 285512195
• Publication date in RUL: 07.08.2026

Record is a part of a journal

• Title: Slovenian veterinary research
• Publisher: Veterinarska fakulteta, Veterinarska fakulteta, Založba Univerze v Ljubljani
• ISSN: 2385-8761
• COBISS.SI-ID: 275836160

Licences

• License: CC BY-SA 4.0, Creative Commons Attribution-ShareAlike 4.0 International
• Link: http://creativecommons.org/licenses/by-sa/4.0/
• Description: This Creative Commons license is very similar to the regular Attribution license, but requires the release of all derivative works under this same license.

Secondary language

• Language: Slovenian
• Title: Profiliranje protimikrobne odpornosti izbranih izolatov E. coli in odkrivanje genov, ki kodirajo ESBL/pAmpC, v jatah brojlerjev v Bosni in Hercegovini z uporabo PCR v realnem času

Abstract

Protimikrobna odpornost (AMR) je vse večji globalni problem, ki ga povzroča neciljna uporaba protimikrobnih sredstev pri živini. Perutnina, zlasti brojlerji, lahko predstavlja pomemben rezervoar odpornih sevov Escherichia (E.) coli. Namen študije je bil izolirati E. coli iz jat brojlerjev in oceniti njihovo in vitro občutljivost za β-laktame, cefalosporine, karbapeneme, tetracikline in fluorokinolone. Poleg tega je bil za odkrivanje genov, ki kodirajo β-laktamaze z razširjenim spektrom (ESBL) in karbapenemaze, uporabljen hkratni PCR v realnem času. Analizirali smo skupno 48 izolatov komenzalne E. coli iz jat brojlerjev v Bosni in Hercegovini (BiH). Fenotipska odpornost, določena z metodo difuzije z diski, je bila opažena pri ampicilinu (87,5 %), amoksicilinu/klavulanski kislini (62,5 %), cefepimu (41,7 %), cefoksitinu (45,8 %), cefotaksimu (50,0 %), ceftazidimu (47,9 %), azitromicinu (58,3 %), ciprofloksacinu (66,7 %) in tetraciklinu (72,9 %). Analiza PCR je potrdila gene blaTEM, blaCTX-M in blaCMY v 24 izolatih (50 %), medtem ko genov blaSHV in genov, ki kodirajo karbapenemaze (blaKPC, blaNDM, blaOXA-48, blaVIM in blaGES), nismo odkrili. Visoka prevalenca večkratno odpornih sevov E. coli poudarja potrebo po izboljšanem upravljanju s protimikrobnimi sredstvi v perutninski proizvodnji. Zmanjšanje uporabe antibiotikov, spodbujanje alternativnih ukrepov za nadzor bolezni in izvajanje sistematičnih programov spremljanja odpornosti so ključni za zmanjšanje AMR na farmah brojlerjev in potencialnega prenosa na ljudi.

• Keywords: protimikrobna odpornost, E. coli, brojlerji, Bosna in Hercegovina