Abstract
Background
Antimicrobial resistance limits traditional treatment options and increases costs. It is therefore important to estimate the magnitude of the problem so as to provide empirical data to guide control efforts. The aim of this study was to investigate the burden and patterns of antimicrobial resistance (AMR) among equine Staphylococcus samples submitted to the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) from 1993 to 2009. Retrospective data of 1711 equine Staphylococcus samples submitted to the UKVDL during the time period 1993 to 2009 were included in the study. Antimicrobial susceptibility testing, that included 16 drugs, were performed using cultures followed by the Kirby-Bauer disk diffusion susceptibility test. The proportion of resistant isolates by animal breed, species of organism, sample source, and time period were computed. Chi-square and Cochran-Armitage trend tests were used to identify significant associations and temporal trends, respectively. Logistic regression models were used to investigate predictors of AMR and multidrug resistance (MDR).
Results
A total of 66.3% of the isolates were resistant to at least one antimicrobial, most of which were Staphylococcus aureus (77.1%), while 25.0% were MDR. The highest level of resistance was to penicillins (52.9%). Among drug classes, isolates had the highest rate of AMR to at least one type of β-lactams (49.2%), followed by aminoglycosides (30.2%). Significant (p < 0.05) associations were observed between odds of AMR and horse breed, species of organism and year. Similarly, significant (p < 0.05) associations were identified between odds of MDR and breed and age. While some isolates had resistance to up to 12 antimicrobials, AMR profiles featuring single antimicrobials such as penicillin were more common than those with multiple antimicrobials.
Conclusion
Demographic factors were significant predictors of AMR and MDR. The fact that some isolates had resistance to up to 12 of the 16 antimicrobials assessed is quite concerning. To address the high levels of AMR and MDR observed in this study, future studies will need to focus on antimicrobial prescription practices and education of both practitioners and animal owners on judicious use of antimicrobials to slow down the development of resistance.
Document Type
Article
Publication Date
2-5-2018
Digital Object Identifier (DOI)
https://doi.org/10.1186/s12917-018-1367-6
Funding Information
The University of Tennessee, Center of Excellence in Livestock Diseases and Human Health (COE) Research Award.
Related Content
The data that support the findings of this study are available from the University of Kentucky Veterinary Diagnostic Laboratory that has legal ownership of the data. The data are not publicly available and should be requested and obtained from the above legal owner that can be reached at 1490 Bull Lea Road, Lexington, KY 40512, USA.
Repository Citation
Adams, Ronita; Smith, Jackie; Locke, Stephan; Phillips, Erica; Erol, Erdal; Carter, Craig N.; and Odoi, Agricola, "An Epidemiologic Study of Antimicrobial Resistance of Staphylococcus Species Isolated from Equine Samples Submitted to a Diagnostic Laboratory" (2018). Veterinary Science Faculty Publications. 41.
https://uknowledge.uky.edu/gluck_facpub/41
Included in
Comparative and Laboratory Animal Medicine Commons, Large or Food Animal and Equine Medicine Commons, Veterinary Microbiology and Immunobiology Commons, Veterinary Preventive Medicine, Epidemiology, and Public Health Commons
Notes/Citation Information
Published in BMC Veterinary Research, v. 14, 42, p. 1-12.
© The Author(s). 2018
This article is 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.