Publikationsdatenbank

Genetic analysis of specific antibiotic resistances in E. coli of veal calves up to eight months (2022)

Art

Vortrag

Autoren

Robé, C. (WE 10)

Baer, J. (WE 10)

Friese, A. (WE 10)

Weise, S. (WE 16)

Gorisek, L. (WE 16)

Merle, R. (WE 16)

Müller, K. E. (WE 18)

Roesler, U. (WE 10)

Kongress

ISAH 2022 : 20th Congress of the International Society for Animal Hygiene

Berlin, 05. – 07.10.2022

Quelle

ISAH 2022 : 20th congress of the international society for animal hygiene : 5.–7. October 2022 — Freie Universität Berlin, Fachbereich Veterinärmedizin Institut für Tier- und Umwelthygien (Hrsg.)

— S. 45–46

Sprache

Englisch

Verweise

URL (Volltext): https://www.vetmed.fu-berlin.de/en/einrichtungen/institute/we10/ISAH-2022/_downloads/Abstract-Book-ISAH2022.pdf

Kontakt

Institut für Veterinär-Epidemiologie und Biometrie

Königsweg 67
14163 Berlin
+49 30 838 56034
epi@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Introduction:
Escherichia coli (E. coli) is used as an indicator bacterium for surveillance to monitor the colonization of livestock animals, including veal calves, with antibiotic resistant bacteria. In Germany, half of the tested commensal E. coli isolates derived from the cecum of veal calves are resistant to at least one antimicrobial class1. However, the currently applied monitoring programs leave aside the variety of different production systems for veal calves in Germany and are mainly based on unselective laboratory methods to detect antibiotic resistances. We investigated fecal samples of veal calves on resistances to highest priority critically important antimicrobials using selective laboratory methods, considering different production systems in Germany. Extended-spectrum beta-lactamases (ESBL) and plasmid mediated AmpC beta-lactamases (pAmpC), resistances to colistin and fluoroquinolones in E. coli were phenotypically and genotypically investigated.

Material & Methods:
Pooled feces samples of veal calves from 106 farms, representing different production systems, were screened for phenotypic resistant E. coli on MacConkey agar supplemented with cefotaxime (1µg/ml), enrofloxacin (2µg/ml) or colistin sulfate (2µg/ml). Distinct colony morphologies per sample and supplemented antibiotic were genotyped using pcr and sanger sequencing after species identification with MALDI-TOF/TOF. Analyses included mobile ESBL- and pAmpC- genes (blaCTX, blaSHV, blaTEM, blaCMY), mobile colistin resistances (mcr-1 to -5) and chromosomal mutations in gyrA and parC (QRDR) as well as mobile fluoroquinolone resistances (PMQR: qnr, qepA, oqxA/B, aac(6’)-Ib-cr).

Results:
In total 78% of the farms were positive for ESBL-/pAmpC- producers, with the highest detection rate of blaCTX-M-1 followed by blaCTX-M-15 and blaCTX-M-14. 10% carried the mcr-1 resistance gene and 85% (QRDR) as well as 17% (PMQR) carried resistances to fluoroquinolones with the most frequent mutations of S83L, D87N/Y/H and S80I and detection of qnrS and aac(6’)-Ib-cr genes on the farms. An impact of the different production systems on the prevalence of the investigated resistance mechanisms was shown, supporting a further differentiation of ‘veal calves’ in surveillance programs based on the production system to improve monitoring of antibiotic resistances.

References:
1 BVL-Report 15.2, Bericht zur Lebensmittelsicherheit (Zoonosen-Monitoring 2019)