Epidemiologic study of results of pulsed-field gel electrophoresis of isolates of Rhodococcus equi obtained from horses and horse farms.
Abstract: To compare isolates of Rhodococcus equi on the basis of geographic source and virulence status by use of pulsed-field gel electrophoresis (PFGE). Methods: 290 isolates of R equi (218 virulent isolates from foals and 72 avirulent isolates from feces, soil, and respiratory tract samples) obtained between 1985 and 2000 from horses and horse farms from 4 countries. Methods: DNA from isolates was digested with the restriction enzyme Asel and tested by use of PFGE. Products were analyzed for similarities in banding patterns by use of dendrograms. A similarity matrix was constructed for isolates, and the matrix was tested for nonrandom distributions of similarity values with respect to groupings of interest. Results: There was little grouping of isolates on the basis of country, virulence status, or region within Texas. Isolates of R equi were generally < 80% similar, as determined by use of PFGE. Isolates from the same farm generally were rarely of the same strain. Conclusions: Considerable chromosomal variability exists among isolates of R equiobtained from the same farm, sites withinTexas, or among countries from various continents. Only rarely will it be possible to link infections to a given site or region on the basis of analysis of isolates by use of PFGE of chromosomal DNA.
Publication Date: 2003-02-27 PubMed ID: 12602583DOI: 10.2460/ajvr.2003.64.153Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The research study explores the genetic variation among Rhodococcus equi isolates from horses and horse farms across different geographic regions, utilizing pulsed-field gel electrophoresis (PFGE). The findings indicate significant genetic diversity among the isolates with little correlation to their geographic or virulence status.
Research Methodology
- The research drew upon 290 isolates of Rhodococcus equi, of which 218 were virulent isolated from foals and 72 were avirulent collected from feces, soil, and respiratory tract samples.
- The isolates were gathered between 1985 and 2000 from horse samples and various horse farms in four different countries.
- The DNA from these isolates was digested with the restriction enzyme Asel and tested via pulsed-field gel electrophoresis (PFGE).
- The PFGE products were analyzed for similarities in banding patterns using dendrograms.
- A similarity matrix was created for the isolates, which was then checked for nonrandom distributions of similarity values in relation to groupings of interest (like geographic region, virulence status, etc.).
Research Findings
- The analysis found little correlation between the genetic profile (based on PFGE) of the isolates and their geographic source, virulence status, or specific region within Texas.
- Generally, the isolates of R. equi were less than 80% similar based on PFGE analysis.
- Rarely, isolates from the same farm were of the same strain, indicating a high level of genetic diversity.
Research Conclusions
- Significant chromosomal variability is observed among R. equi isolates from the same farm, sites within Texas, or among different countries.
- Infections could rarely be linked with a specific site or geographic region based on PFGE analysis.
- This study challenges the assumption that R. equi isolates from the same farm or geographic region are genetically similar, suggesting a complex and diverse genetic backdrop for these organisms.
This research, therefore, presents useful insights into the genetic diversity of R. equi isolates across varying geographic and environmental contexts, which may have implications for infection tracking and control strategies.
Cite This Article
APA
Cohen ND, Smith KE, Ficht TA, Takai S, Libal MC, West BR, DelRosario LS, Becu T, Leadon DP, Buckley T, Chaffin MK, Martens RJ.
(2003).
Epidemiologic study of results of pulsed-field gel electrophoresis of isolates of Rhodococcus equi obtained from horses and horse farms.
Am J Vet Res, 64(2), 153-161.
https://doi.org/10.2460/ajvr.2003.64.153 Publication
Researcher Affiliations
- Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4475, USA.
MeSH Terms
- Actinomycetales Infections / epidemiology
- Actinomycetales Infections / microbiology
- Actinomycetales Infections / veterinary
- Animals
- Argentina / epidemiology
- DNA, Bacterial / analysis
- Electrophoresis, Gel, Pulsed-Field
- Evolution, Molecular
- Horse Diseases / microbiology
- Horses / microbiology
- Ireland / epidemiology
- Japan / epidemiology
- Phylogeny
- Rhodococcus equi / genetics
- Rhodococcus equi / isolation & purification
- Rhodococcus equi / pathogenicity
- Texas / epidemiology
- Virulence
Citations
This article has been cited 11 times.- Álvarez-Narváez S, Giguère S, Cohen N, Slovis N, Vázquez-Boland JA. Spread of Multidrug-Resistant Rhodococcus equi, United States. Emerg Infect Dis 2021 Feb;27(2):529-537.
- Álvarez-Narváez S, Giguère S, Anastasi E, Hearn J, Scortti M, Vázquez-Boland JA. Clonal Confinement of a Highly Mobile Resistance Element Driven by Combination Therapy in Rhodococcus equi. mBio 2019 Oct 15;10(5).
- Bujold AR, Lani NR, Sanz MG. Strain-to-strain variation of Rhodococcus equi growth and biofilm formation in vitro. BMC Res Notes 2019 Aug 19;12(1):519.
- Folmar CN, Cywes-Bentley C, Bordin AI, Rocha JN, Bray JM, Kahn SK, Schuckert AE, Pier GB, Cohen ND. In vitro evaluation of complement deposition and opsonophagocytic killing of Rhodococcus equi mediated by poly-N-acetyl glucosamine hyperimmune plasma compared to commercial plasma products. J Vet Intern Med 2019 May;33(3):1493-1499.
- Witkowski L, Rzewuska M, Takai S, Chrobak-Chmiel D, Kizerwetter-Świda M, Feret M, Gawryś M, Witkowski M, Kita J. Molecular characterization of Rhodococcus equi isolates from horses in Poland: pVapA characteristics and plasmid new variant, 85-kb type V. BMC Vet Res 2017 Jan 26;13(1):35.
- Rocha JN, Cohen ND, Bordin AI, Brake CN, Giguère S, Coleman MC, Alaniz RC, Lawhon SD, Mwangi W, Pillai SD. Oral Administration of Electron-Beam Inactivated Rhodococcus equi Failed to Protect Foals against Intrabronchial Infection with Live, Virulent R. equi. PLoS One 2016;11(2):e0148111.
- McQueen CM, Dindot SV, Foster MJ, Cohen ND. Genetic Susceptibility to Rhodococcus equi. J Vet Intern Med 2015 Nov-Dec;29(6):1648-59.
- Whitfield-Cargile CM, Cohen ND, Suchodolski J, Chaffin MK, McQueen CM, Arnold CE, Dowd SE, Blodgett GP. Composition and Diversity of the Fecal Microbiome and Inferred Fecal Metagenome Does Not Predict Subsequent Pneumonia Caused by Rhodococcus equi in Foals. PLoS One 2015;10(8):e0136586.
- Witkowski L, Rzewuska M, Cisek AA, Chrobak-Chmiel D, Kizerwetter-Świda M, Czopowicz M, Welz M, Kita J. Prevalence and genetic diversity of Rhodococcus equi in wild boars (Sus scrofa), roe deer (Capreolus capreolus) and red deer (Cervus elaphus) in Poland. BMC Microbiol 2015 May 22;15:110.
- da Silveira BP, Cohen ND, Lawhon SD, Watson RO, Bordin AI. Protective immune response against Rhodococcus equi: An innate immunity-focused review. Equine Vet J 2025 May;57(3):563-586.
- Kaczmarkowska A, Kwiecień E, Didkowska A, Stefańska I, Rzewuska M, Anusz K. The Genetic Diversity and Antimicrobial Resistance of Pyogenic Pathogens Isolated from Porcine Lymph Nodes. Antibiotics (Basel) 2023 Jun 7;12(6).
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