title: The molecular identification of Streptococcus equi subsp. equi strains isolated within New Zealand.
abstract: OBJECTIVE
  To identify Streptococcus equi subsp. equi (S. equi) by PCR analysis and obtain isolates by culture, in order to investigate the strains of S. equi infecting horses within New Zealand.
  
  
  METHODS
  A diagnostic PCR, based on the amplification of the seeI gene for S. equi, was used on 168 samples submitted from horses with and without clinical signs of strangles. Samples were also processed and cultured on selective media for the isolation of β-haemolytic colonies. In addition, the hypervariable region of the seM gene of S. equi was amplified and then sequenced for strain typing purposes.
  
  
  RESULTS
  Of the 168 samples, 35 tested positive for S. equi using PCR. Thirty-two confirmed samples were from horses with a clinical diagnosis of strangles and three were from horses where clinical information was unavailable. Only 22/35 (63%) confirmed S. equi samples were successfully isolated following culture. Strain typing demonstrated that two novel seM alleles of S. equi were found in New Zealand with SeM-99 strains being restricted to the North Island while SeM-100 strains were found in both North and South Islands.
  
  
  CONCLUSIONS
  The application of PCR for the laboratory confirmation of strangles allowed for a rapid and sensitive identification of S. equi. Moreover, seM typing revealed that within the samples examined two strains of S. equi co-circulated within the North Island of New Zealand but only one strain in the South Island.
  
  
  CONCLUSIONS
  PCR reduces the time required to obtain laboratory confirmation of strangles compared with culture methods. It also has greater sensitivity in detecting S. equi infections, which is of particular importance in the detection of carrier animals which normally shed low numbers of bacteria. Additionally, seM molecular typing can differentiate between bacterial strains, assisting in the monitoring of local strains of S. equi subsp. equi causing disease.
authors.affiliation: a Biological Sciences , The University of Waikato , Private Bag 3105, Hamilton 3240 , New Zealand.
authors.forename: O A
authors.initials: OA
authors.lastname: Patty
authors.forename: R T M
authors.initials: RT
authors.lastname: Cursons
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D006734:Horse Diseases / Q000453:epidemiology / Q000382:microbiology*; D006736:Horses; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D009520:New Zealand / Q000453:epidemiology; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D018502:Streptococcus equi / Q000145:classification* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins