OBJECTIVE: To compare isolates of Rhodococcus equi on the basis of geographic source and virulence status by use of pulsed-field gel electrophoresis (PFGE). SAMPLE POPULATION: 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. PROCEDURE: 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 AND CLINICAL RELEVANCE: 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.
OBJECTIVE: To compare isolates of Rhodococcus equi on the basis of geographic source and virulence status by use of pulsed-field gel electrophoresis (PFGE). SAMPLE POPULATION: 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. PROCEDURE: 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 AND CLINICAL RELEVANCE: 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.
Authors: Lucjan Witkowski; Magdalena Rzewuska; Shinji Takai; Dorota Chrobak-Chmiel; Magdalena Kizerwetter-Świda; Małgorzata Feret; Marta Gawryś; Maciej Witkowski; Jerzy Kita Journal: BMC Vet Res Date: 2017-01-26 Impact factor: 2.741
Authors: Chelsea N Folmar; Colette Cywes-Bentley; Angela I Bordin; Joana N Rocha; Jocelyne M Bray; Susanne K Kahn; Amanda E Schuckert; Gerald B Pier; Noah D Cohen Journal: J Vet Intern Med Date: 2019-04-29 Impact factor: 3.333
Authors: Canaan M Whitfield-Cargile; Noah D Cohen; Jan Suchodolski; M Keith Chaffin; Cole M McQueen; Carolyn E Arnold; Scot E Dowd; Glenn P Blodgett Journal: PLoS One Date: 2015-08-25 Impact factor: 3.240
Authors: Joana N Rocha; Noah D Cohen; Angela I Bordin; Courtney N Brake; Steeve Giguère; Michelle C Coleman; Robert C Alaniz; Sara D Lawhon; Waithaka Mwangi; Suresh D Pillai Journal: PLoS One Date: 2016-02-01 Impact factor: 3.240