New Findings in Veterinary Microbiology

New Findings in Veterinary Microbiology

Evaluation of the Antimicrobial Resistance Pattern of Escherichia coli Isolates Recovered from Pigeons in the Sistan Region Using the Multidrug Resistance Index and Cluster Analysis

Document Type : Original Article

Authors
Alireza Mirzaei 1
Ahmad Rashki 2
mohsen najimi 3
Saeed Salari 4
1 Genetics Laboratory specialist of Zabol univercity
2 Department of Pathobiology, Faculty of Veterinary Medicine, University of Zabol, Zabol, Iran
3 Department of pathobiology, Faculty of Veterinary Medicine, University of Zabol, Zabol, Iran.
4 Department of Pathobiology, Faculty of Veterinary Medicine, University of Zabol, IR
10.22034/nfvm.2026.586183.1317
Abstract
Urban and semi-domesticated pigeons, due to their continuous contact with human environments, contaminated sources, waste materials, and other animals, may play a role in the dissemination cycle of antibiotic-resistant bacteria. Escherichia coli (E. coli), as one of the main indicator intestinal bacteria in birds, can be used for monitoring antimicrobial resistance within the One Health framework. The aim of this study was to isolate E. coli from pigeons in the Sistan region and to investigate their antimicrobial resistance patterns, multidrug resistance status, and similarity structure of resistance profiles using clustering analyses.
In this cross-sectional study, cloacal samples were collected from 136 pigeons in the Sistan region. The samples were cultured on MacConkey agar, eosin methylene blue agar, and blood agar. Suspected isolates were identified using standard morphological and biochemical tests. Hemolytic activity was assessed on blood agar. Antimicrobial susceptibility testing was performed using the Kirby–Bauer disk diffusion method on Mueller–Hinton agar, and the results were interpreted according to CLSI guidelines. Resistance data were coded as binary variables, and resistance frequencies, multidrug resistance status, K-means clustering, hierarchical clustering based on Jaccard distance, and principal component analysis were evaluated.
Keywords
E. coli
pigeon
antimicrobial resistance
Subjects

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New Findings in Veterinary Microbiology
Volume 9, Issue 1
Spring 2026
Pages 74-88

  • Receive Date 11 June 2026
  • Accept Date 12 June 2026