title: Use of repetitive sequence-based polymerase chain reaction for molecular epidemiologic analysis of Streptococcus equi subspecies equi.
abstract: OBJECTIVE
  To determine whether repetitive sequence-based polymerase chain reaction (rep-PCR) could be used to differentiate Streptococcus equi isolates, to examine S equi isolates from throughout the world, and to determine whether a horse had > 1 subtype of S equi during an outbreak of disease.
  
  
  METHODS
  An initial group of 32 S equi isolates, 63 S equi isolates from various geographic areas, and 17 S equi isolates obtained during outbreaks of disease.
  
  
  METHODS
  An aliquot of S equi genomic DNA was amplified, using enterobacterial repetitive intergenic consensus primers. Gel electrophoresis was performed on 1.5% agarose gels, and a computed-assisted program was used to compare rep-PCR results.
  
  
  RESULTS
  Use of these primers to analyze 100 ng of S equi genomic DNA resulted in patterns of 6 to 14 bands. The 32 initial isolates were separated into 7 rep-PCR subtypes. There were 30 rep-PCR subtypes found among 29 S equi isolates obtained from Minnesota, Michigan, Canada, and Australia and 34 S equi isolates obtained from Kentucky and other sources. Furthermore, the same clone was identified in several horses during an outbreak of disease. Infected horses on the same farm all had a single clone of S equi.
  
  
  CONCLUSIONS
  Analysis of these results suggests that rep-PCR is useful for delineating S equi into rep-PCR subtypes. Results revealed that isolates with the same geographic source or similar date of collection did not always have the same rep-PCR subtype. A single clone of S equi usually predominated during an outbreak of disease.
authors.affiliation: Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA.
authors.forename: G M
authors.initials: GM
authors.lastname: Al-Ghamdi
authors.forename: V
authors.initials: V
authors.lastname: Kapur
authors.forename: T R
authors.initials: TR
authors.lastname: Ames
authors.forename: J F
authors.initials: JF
authors.lastname: Timoney
authors.forename: D N
authors.initials: DN
authors.lastname: Love
authors.forename: M A
authors.initials: MA
authors.lastname: Mellencamp
mesh_terms: D000818:Animals; D001315:Australia / Q000453:epidemiology; D016172:DNA Fingerprinting / Q000662:veterinary; D017931:DNA Primers / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D004196:Disease Outbreaks / Q000145:classification / Q000662:veterinary*; D004587:Electrophoresis, Agar Gel / Q000662:veterinary; D005060:Europe / Q000453:epidemiology; D006734:Horse Diseases / Q000453:epidemiology / Q000382:microbiology*; D006736:Horses; D015146:Midwestern United States / Q000453:epidemiology; D009864:Ontario / Q000453:epidemiology; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D018502:Streptococcus equi / Q000737:chemistry / Q000145:classification* / Q000235:genetics
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial