<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The purpose of this study was to detect the antibiotic resistance of forty-one <italic>Escherichia coli</italic> isolates from the intestinal contents of slaughtered broiler chickens using the disk diffusion method according to Kirby-Bauer. Mueller-Hinton agar plates were inoculated with 0.1 ml overnight broth cultures of individual <italic>E. coli</italic> isolates and the disks with the following concentrations of antibiotics were applied onto them: ampicillin (10 μg), cefotaxime (30 μg), gentamicin (10 μg), streptomycin (10 μg), azithromycin (15 μg), tetracycline (30 μg), ciprofloxacin (30 μg) and levofloxacin (3 μg). After the incubation at 37 °C for 16—18 hours, the inhibition zones were measured and interpreted in accordance with the Clinical and Laboratory Standard Institute (CLSI) zone diameter breakpoints. Almost all <italic>E. coli</italic> isolates showed resistance to tetracycline (92.68 %), most of them were resistant to gentamicin (75.61 %) and levofloxacine (70.73 %). Phenotypic resistance to tetracycline was further confirmed with the help of the Polymerase Chain Reaction (PCR) procedure focused on the presence of specific tet(A) and tet(B) genes. These genes were detected in all 41 <italic>E. coli</italic> isolates. On the contrary, <italic>E. coli</italic> isolates were highly susceptible to both azithromycin and streptomycin. In conclusion, the study highlighted the role of commensal <italic>E. coli</italic> bacteria isolated from the intestines of broiler chickens as an important reservoir of tetracycline resistance genes.</p></abstract>

The purpose of this study was to detect the antibiotic resistance of forty-one Escherichia coli isolates from the intestinal contents of slaughtered broiler chickens using the disk diffusion method according to Kirby-Bauer. Mueller-Hinton agar plates were inoculated with 0.1 ml overnight broth cultures of individual E. coli isolates and the disks with the following concentrations of antibiotics were applied onto them: ampicillin (10 μg), cefotaxime (30 μg), gentamicin (10 μg), streptomycin (10 μg), azithromycin (15 μg), tetracycline (30 μg), ciprofloxacin (30 μg) and levofloxacin (3 μg). After the incubation at 37 °C for 16—18 hours, the inhibition zones were measured and interpreted in accordance with the Clinical and Laboratory Standard Institute (CLSI) zone diameter breakpoints. Almost all E. coli isolates showed resistance to tetracycline (92.68 %), most of them were resistant to gentamicin (75.61 %) and levofloxacine (70.73 %). Phenotypic resistance to tetracycline was further confirmed with the help of the Polymerase Chain Reaction (PCR) procedure focused on the presence of specific tet(A) and tet(B) genes. These genes were detected in all 41 E. coli isolates. On the contrary, E. coli isolates were highly susceptible to both azithromycin and streptomycin. In conclusion, the study highlighted the role of commensal E. coli bacteria isolated from the intestines of broiler chickens as an important reservoir of tetracycline resistance genes.

Antibiotic Resistance of <italic>Escherichia Coli</italic> Isolated from Broiler Chickens

Department of Food Hygiene and Technology, Institute of Meat Hygiene and Technology

University of Veterinary Medicine and Pharmacy in Kosice

Folia Veterinaria

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Antibiotic Resistance of  Isolated from Broiler Chickens

The purpose of this study was to detect the antibiotic resistance of forty-one Escherichia coli isolates from the intestinal contents of slaughtered broiler...

Antibiotic Resistance of Escherichia Coli Isolated from Broiler Chickens

Published Online: Sep 28, 2019

Page range: 1 - 8

Received: Apr 29, 2019

Accepted: Jul 04, 2019

DOI: https://doi.org/10.2478/fv-2019-0021

Keywords
antibiotics, broilers, disk diffusion method, PCR

© 2019 M. Sciberras et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Antibiotic Resistance of Escherichia Coli Isolated from Broiler Chickens

Published Online: Sep 28, 2019

Page range: 1 - 8

Received: Apr 29, 2019

Accepted: Jul 04, 2019

DOI: https://doi.org/10.2478/fv-2019-0021

Keywordsantibiotics, broilers, disk diffusion method, PCR

© 2019 M. Sciberras et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
antibiotics, broilers, disk diffusion method, PCR