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Ali Goudarztalejerdi

Ali Goudarztalejerdi

Academic rank: Assistant Professor
ORCID:
Education: PhD.
ScopusId: 56764626400
HIndex:
Faculty: Faculty of Veterinary Medicine
Address:
Phone: 08134227350

Research

Title
High Prevalence of Multi-Drug Resistance and Biofilm-Formation Ability Among Avian Escherichia coli Isolated from Broilers in Iran
Type
Presentation
Keywords
Multi-drug resistance; MDR, biofilm, Avian-Pathogenic Escherichia coli; APEC, Avian Faecal Escherichia coli; AFEC, colibacillosis, broiler.
Year
2023
Researchers Ali Goudarztalejerdi ، Abdolmajid Mohammadzadeh ، ،

Abstract

Objectives: The present study was conducted to determine the antimicrobial resistance pattern and biofilm- formation ability in 100 Avian-Pathogenic Escherichia coli (APEC) isolated from colibacillosis-suspected broilers, and 100 Avian Faecal E. coli (AFEC) isolates from healthy broilers in Hamedan, Iran. Materials & Methods: The antibacterial susceptibility testing of avian E. coli strains was performed using the Kirby-Bauer disk diffusion method according to the Clinical Laboratory Standard Institute guidelines (CLSI, 2019). All isolates were screened by PCR for antimicrobial resistance genes, class 1 and 2 integrons and biofilm-associated genes. Besides, we assessed the possible relationship between biofilm-formation ability, antibiotic resistance patterns, genetic background and, the pathogenicity of APEC strains. Results & Conclusion: 81% of APEC and 73% of AFEC isolates showed multi-drug resistance (MDR) phenotype, in addition, 45% of the APEC and 21% of the AFEC strains showed biofilm-formation ability. This is the first report of the biofilm formation ability in E. coli isolated from broilers in Iran. The most prevalent antibiotic resistance gene in APEC strains was tetA (68%), followed by sul1(63%), dfrA1-like (51%) and, blaTEM (30%), whereas in AFEC strains, the frequencies of the antibiotic resistance genes were tetA (63%), sul1(58%), dfrA1-like (49%) and, blaTEM (22%). Out of 81 MDR APEC isolates, 53(65.4%), and 38 (46.91%) isolates were positive for intI1 and intI2 genes, respectively. In the AFEC strains intI1 and intI2 genes were presented in 57 and 33 isolates, respectively. All APEC isolates belonging to phylogenetic groups B1, B2 and C were MDR. The results of the present study indicate that isolates with biofilm-forming ability show more MDR properties, and probably have more pathogenicity to broilers.