Investigating the Antibiotic Resistance of Escherichia coli Isolated from Poultry Infected with Colibacillosis in Broiler Farms of Chaharmahal and Bakhtiari Province

Document Type : Original Article

Authors
Seyyed Sattar Tohidifar 1
Seyyed Mohammad Ziaei 2
Abdolkarim Zamani Moghadam 3
Seyyed Reza Abtahi 4
Kazem Norouzi 5
1 Department of Animal Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
2 Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
3 Department of Clinical Sciences,, Faculty of Veterinary Medicine,, Shahrekord University, Shahrekord, Iran.
4 Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran.
5 PhD Student in Veterinary Reproductive Biotechnology, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran.
10.22034/ijvcs.2026.15029.1099
Abstract
The causative agent of colibacillosis is Escherichia coli, transmitted through water, manure, contaminated air, contaminated breeding equipment, or from the mother to the egg, and finally to the chick. Over the last three decades, several cases of resistance to florfenicol and quinolones have been reported in humans and livestock. One of the reasons for the emergence of resistance in humans is the widespread use of these drugs in poultry farming.
This study aims to investigate antibiotic resistance levels in Escherichia coli isolates from poultry farms in Chaharmahal and Bakhtiari province. In this research, 204 samples from broiler farms that visited the clinic of Shahrekord University Veterinary School between 2019 and 2024 were examined and subjected to antibiogram testing.
According to the obtained results, resistance was observed as follows: oxacillin 100.00%, erythromycin 97.06%, oxytetracycline 91.18%, trimethoprim-sulfamethoxazole 86.76%, flumequine 80.88%, difloxacin 79.90%, danofloxacin 77.94%, ampicillin 75.98%, enrofloxacin 72.06%, ciprofloxacin 68.14%, florfenicol 61.28%, lincospectin 40.69%, and fosfomycin 27.95%.
Based on these findings, Fosfomycin, Lincospectin, and Florfenicol are antibiotics with the least resistance compared to others. Our results indicate a concerning level of antibiotic resistance in colibacillosis infection; This poses a serious risk to both the poultry industry in the country and public health.
Keywords
Antibiogram
Antibiotic Resistance
Broiler
Collibacillosis
Subjects
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Iranian Journal of Veterinary Clinical Sciences
Volume 20, Issue 1 - Serial Number 34
Spring &Summer 2026
September 2026
Pages 57-67