A longitudinal study reveals persistence of antimicrobial resistance on livestock farms is not due to antimicrobial usage alone

Smith, Richard P.; May, Hannah E.; AbuOun, Manal; Stubberfield, Emma; Gilson, Daniel; Chau, Kevin K.; Crook, Derrick; Shaw, Liam P.; Read, Daniel S. ORCID: https://orcid.org/0000-0001-8546-5154; Stoesser, Nicole; Vilar, Maria Jose; Anjum, Muna F.. 2023 A longitudinal study reveals persistence of antimicrobial resistance on livestock farms is not due to antimicrobial usage alone. Frontiers in Microbiology, 14, 1070340. 12, pp. https://doi.org/10.3389/fmicb.2023.1070340

Before downloading, please read NORA policies.

Preview

Text
N535489JA.pdf - Published Version
Available under License Creative Commons Attribution 4.0.
Download (1MB) | Preview

Official URL: http://dx.doi.org/10.3389/fmicb.2023.1070340

Abstract/Summary

•Introduction: There are concerns that antimicrobial usage (AMU) is driving an increase in multi-drug resistant (MDR) bacteria so treatment of microbial infections is becoming harder in humans and animals. The aim of this study was to evaluate factors, including usage, that affect antimicrobial resistance (AMR) on farm over time. •Methods: A population of 14 cattle, sheep and pig farms within a defined area of England were sampled three times over a year to collect data on AMR in faecal Enterobacterales flora; AMU; and husbandry or management practices. Ten pooled samples were collected at each visit, with each comprising of 10 pinches of fresh faeces. Up to 14 isolates per visit were whole genome sequenced to determine presence of AMR genes. •Results: Sheep farms had very low AMU in comparison to the other species and very few sheep isolates were genotypically resistant at any time point. AMR genes were detected persistently across pig farms at all visits, even on farms with low AMU, whereas AMR bacteria was consistently lower on cattle farms than pigs, even for those with comparably high AMU. MDR bacteria was also more commonly detected on pig farms than any other livestock species. •Discussion: The results may be explained by a complex combination of factors on pig farms including historic AMU; co-selection of AMR bacteria; variation in amounts of antimicrobials used between visits; potential persistence in environmental reservoirs of AMR bacteria; or importation of pigs with AMR microbiota from supplying farms. Pig farms may also be at increased risk of AMR due to the greater use of oral routes of group antimicrobial treatment, which were less targeted than cattle treatments; the latter mostly administered to individual animals. Also, farms which exhibited either increasing or decreasing trends of AMR across the study did not have corresponding trends in their AMU. Therefore, our results suggest that factors other than AMU on individual farms are important for persistence of AMR bacteria on farms, which may be operating at the farm and livestock species level.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.3389/fmicb.2023.1070340
UKCEH and CEH Sections/Science Areas:	Soils and Land Use (Science Area 2017-)
ISSN:	1664-302X
Additional Information. Not used in RCUK Gateway to Research.:	Open Access paper - full text available via Official URL link.
Additional Keywords:	antimicrobial usage, antimicrobial resistance, cattle, sheep, pigs, longitudinal
NORA Subject Terms:	Agriculture and Soil Science Biology and Microbiology
Related URLs:	Dataset
Date made live:	08 Aug 2023 15:02 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/535489

Item Type:

Publication - Article

Digital Object Identifier (DOI):

https://doi.org/10.3389/fmicb.2023.1070340

UKCEH and CEH Sections/Science Areas:

Soils and Land Use (Science Area 2017-)

ISSN:

1664-302X

Additional Information. Not used in RCUK Gateway to Research.:

Open Access paper - full text available via Official URL link.

Additional Keywords:

antimicrobial usage, antimicrobial resistance, cattle, sheep, pigs, longitudinal