Antimicrobial resistance of commensal Enterococcus faecalis and Enterococcus faecium from food-producing animals in Russia

Vet World Vol.15 March-2022 Article-9

Research Article

Veterinary World, 15(3): 611-621

https://doi.org/10.14202/vetworld.2022.611-621

Dmitry A. Makarov¹, Olga E. Ivanova², Anastasia V. Pomazkova², Maria A. Egoreva², Olga V. Prasolova², Sergey V. Lenev², Maria A. Gergel³, Nataliya K. Bukova⁴, and Sergey Yu Karabanov⁵

1. Department of Food and Feed Safety, Federal State Budgetary Institution, The Russian State Center for Animal Feed and Drug Standardization and Quality (VGNKI), Moscow, Russia.
2. Department of Biotechnology, Federal State Budgetary Institution, The Russian State Center for Animal Feed and Drug Standardization and Quality (VGNKI), Moscow, Russia.
3. Department of Immunobiological Drugs, Federal State Budgetary Institution, The Russian State Center for Animal Feed and Drug Standardization and Quality (VGNKI), Moscow, Russia.
4. Testing Centre, Federal State Budgetary Institution The Russian State Center for Animal Feed and Drug Standardization and Quality (VGNKI), Moscow, Russia.
5. Department of Experimental Clinic and Research Laboratory for Bioactive Substances of Animal Origin, V. M. Gorbatov Federal Research Center for Food Systems, Moscow, Russia.

Background and Aim: Although Enterococcus faecalis and Enterococcus faecium are common members of human and animal gut microbiota, their resistance to different antimicrobials makes them important pathogens. Multidrug-resistant enterococci often contaminate foods of animal origin at slaughterhouses. The World Health Organization and the World Organization for Animal Health recommend including animal-derived enterococci in antimicrobial resistance (AMR) monitoring programs. This study aimed to fill a literature gap by determining the current AMR prevalence of E. faecalis and E. faecium from different food-producing animals in Russia.

Materials and Methods: Samples of biomaterial were taken from chickens (n=187), cattle (n=155), pigs (n=49), turkeys (n=34), sheep (n=31), and ducks (n=31) raised at 28 farms in 15 regions of Russia. Isolates of E. faecalis (n=277) and of E. faecium (n=210) (487 isolates in total; 1 isolate per sample) were tested for resistance to 12 antimicrobials from 11 classes using the broth microdilution method. Three criteria were used for the interpretation of minimum inhibitory concentration: Epidemiological cutoff values (ECOFFs) from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) clinical breakpoints. The AMR cloud online platform was used for data processing and statistical analysis.

Results: A difference of >10% was found between E. faecalis and E. faecium resistance to several antimicrobials (erythromycin, gentamycin, tetracycline, chloramphenicol, ciprofloxacin, and streptomycin). In total, resistance to most antimicrobials for enterococci isolates of both species taken from turkeys, chicken, and pigs was higher than cattle, sheep, and ducks. The highest levels were found for turkeys and the lowest for ducks. Among antimicrobials, resistance to bacitracin and virginiamycin was 88-100% in nearly all cases. High levels of clinical resistance were found for both bacteria species: Rifampicin (44-84%) from all animals, tetracycline (45-100%) from poultry and pigs, and erythromycin (60-100%), ciprofloxacin (23-100%), and trimethoprim-sulfamethoxazole (33-53%) from chickens, turkeys, and pigs. No vancomycin-resistant isolates were found. Most isolates were simultaneously resistant to one–three classes of antimicrobials, and they were rarely resistant to more than three antimicrobials or sensitive to all classes.

Conclusion: Differences in resistance between enterococci from different farm animals indicate that antimicrobial application is among the crucial factors determining the level of resistance. Conversely, resistance to rifampicin, erythromycin, tetracycline, and ciprofloxacin found in enterococci from farm animals in our study was notably also found in enterococci from wild animals and birds. Our results may be partly explained by the intrinsic resistance of E. faecium and E. faecalis to some antimicrobials, such as trimethoprim/sulfamethoxazole and bacitracin. Keywords: animals, antimicrobial resistance, enterococci, Enterococcus faecium, Enterococcus faecalis, livestock.

Keywords: animals, antimicrobial resistance, enterococci, Enterococcus faecium, Enterococcus faecalis, livestock.

How to cite this article: Makarov DA, Ivanova OE, Pomazkova AV, Egoreva MA, Prasolova OV, Lenev SV, Gergel MA, Bukova NK, Karabanov SY (2022) Antimicrobial resistance of commensal Enterococcus faecalis and Enterococcus faecium from food-producing animals in Russia, Veterinary World, 15(3): 611-621.

Received: 14-11-2021 Accepted: 08-02-2022 Published online: 18-03-2022

Corresponding author: Dmitry A. Makarov E-mail: phorez@yandex.ru

DOI: 10.14202/vetworld.2022.611-621

Copyright: Makarov, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.