Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Mar 8;21(1):160.
doi: 10.1186/s12917-025-04626-x.

Antimicrobial resistance, virulence gene profiles, and phylogenetic groups of Escherichia coli isolated from healthy broilers and broilers with colibacillosis in Thailand

Sudtisa Laopiem  1 , Kriangkrai Witoonsatian  1 , Sittinee Kulprasetsri  1 , Pun Panomwan  1 , Chutima Pathomchai-Umporn  1 , Raktipon Kamtae  2 , Pichai Jirawattanapong  1 , Thaweesak Songserm  3 , Nuananong Sinwat  4
Affiliations

Antimicrobial resistance, virulence gene profiles, and phylogenetic groups of Escherichia coli isolated from healthy broilers and broilers with colibacillosis in Thailand

Sudtisa Laopiem et al. BMC Vet Res. .

Abstract

Background: Multidrug resistance in Escherichia coli has a significant global impact on poultry production. This study aimed to determine the phenotypic and genotypic backgrounds of antimicrobial resistance (AMR) and virulence gene profiles of E. coli strains isolated from diseased and healthy broilers. A total of 211 E. coli isolates were recovered from diseased (n = 110) and healthy broilers (n = 101). All the isolates were subjected to antimicrobial susceptibility testing. A PCR-based technique was applied to screen AMR genes, virulence genes and analyze phylogenetic groups.

Results: Phylogenetic groups B1 and D were the most prevalent for E. coli isolated from diseased and healthy birds. Among virulence genes, the detection rates of cva/cvi, iutA, iucD, iroN, iss and ompT were considerably greater in E.coli strains from diseased birds than in healthy birds. The virulence gene pattern of hlyF-iutA-iucD-iroN-iss-ompT (16.4%) was frequently observed in E.coli isolated from diseased birds, whereas approximately 22.8% of E.coli from healthy birds did not carry any virulence genes. Analysis of AMR profiles revealed that 58.3% of E.coli were resistant to multiple classes of antibiotics, and 96.7% carried at least one antibiotic resistance gene AMR genes.

Conclusion: The findings of this study demonstrate the variable distribution of phylogenetic groups and virulence genes. E.coli strains isolated from broilers had multidrug resistance profiles. The study emphasizes the need for continuous monitoring of AMR emergence in E. coli from broilers. This monitoring allows for early detection and implementation of strategies to control the spread of resistant strains.

Keywords: Escherichia coli; Antimicrobial resistance; Diseased broilers; Healthy broilers.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: All procedures for sample collection from diseased and healthy broilers in this study were approved by the KASETSART UNIVERSITY Institutional Animal Care and Use Committee (ACKU62-VET-040) and found to be in accordance with the guidelines of animal care and use established by the Ethical Review Board of the Office of National Research Council of Thailand (NRCT) for the conduct of scientific research. The committee approved and permitted the animal care and use to be conducted as outlined in the research study and animal use protocol. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
The percentage of strains showing antibiotic resistance in E.coli from diseased and Healthy broilers (n = 211)
See this image and copyright information in PMC

References

    1. Kathayat D, Lokesh D, Ranjit S, Rajashekara G. Avian pathogenic Escherichia coli (Apec): an overview of virulence and pathogenesis factors, zoonotic potential, and control strategies. Pathogens. 2021;10(4):1–32. - PMC - PubMed
    1. Lutful Kabir SM. Avian colibacillosis and salmonellosis: A closer look at epidemiology, pathogenesis, diagnosis, control and public health concerns. Int J Environ Res Public Health. 2010;7(1):89–114. - PMC - PubMed
    1. Ovi F, Zhang L, Nabors H, Jia L, Adhikari P. A compilation of virulence-associated genes that are frequently reported in avian pathogenic Escherichia coli (APEC) compared to other E. coli. J Appl Microbiol. 2023;134(3):1–20. - PubMed
    1. De Carli S, Ikuta N, Lehmann FKM, Da Silveira VP, De Melo Predebon G, Fonseca ASK, Lunge VR. Virulence gene content in Escherichia coli isolates from poultry flocks with clinical signs of colibacillosis in Brazil. Poult Sci. 2015;94(11):2635–40. - PubMed
    1. Aberkane C, Messaï A, Messaï CR, Boussaada T. Antimicrobial resistance pattern of avian pathogenic Escherichia coli with detection of extended-spectrum β-lactamase-producing isolates in broilers in East Algeria. Vet World. 2023;16(3):449–54. - PMC - PubMed

MeSH terms

LinkOut - more resources