title: Identification of three clusters of canine intestinal spirochaetes by biochemical and 16S rDNA sequence analysis.
abstract: It has been suggested that canine intestinal spirochaetes consist of Brachyspira pilosicoli and a group of strains that has been provisionally designated 'Brachyspira canis'. The purpose of the present study was to compare 22 spirochaete isolates that were obtained from intestinal specimens of dogs in Sweden (n = 12), Norway (n = 4), the United States (n = 3), Australia (n = 2) and Germany (n = 1) with type and reference strains, as well as field isolates, of Brachyspira species by five biochemical tests and determination of almost-complete 16S rDNA sequences. In an evolutionary tree derived from 16S rDNA sequences, the canine isolates grouped into three clusters. One cluster included the type strain of porcine B. pilosicoli, whereas a second larger cluster, which was monophyletic, contained a canine strain that was identified previously as 'B. canis'. The third cluster consisted of three canine isolates of Scandinavian origin, which grouped together with the type strain of the species Brachyspira alvinipulli (pathogenic to chicken). These three genotypes, which were identified on the basis of 16S rDNA sequences, corresponded to four phenotypic groups based on biochemical testing. Two biochemical tests, hippurate hydrolysis and alpha-galactosidase production, were sufficient for rapid identification of each canine cluster.
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Karl-Erik
authors.initials: KE
authors.lastname: Johansson
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Gerald E
authors.initials: GE
authors.lastname: Duhamel
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Bjarne
authors.initials: B
authors.lastname: Bergsjö
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Eva Olsson
authors.initials: EO
authors.lastname: Engvall
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Marianne
authors.initials: M
authors.lastname: Persson
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Bertil
authors.initials: B
authors.lastname: Pettersson
authors.affiliation: National Veterinary Institute, Department of Bacteriology, SE-75189 and Department of Veterinary Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden 2Department of Veterinary and Biochemical Sciences, University of Nebraska-Lincoln, USA 3Department of Bacteriology, National Veterinary Institute, Oslo, Norway 4Department of Disease Control and Biosecurity, National Veterinary Institute, Uppsala, Sweden 5Department of Biochemistry and Biotechnology, The Royal Institute of Technology, Stockholm, Sweden 6Department of Large Animal Clinical Sciences, Swedish University of Agricultural Sciences, Box 7018, SE-75007, Uppsala, Sweden.
authors.forename: Claes
authors.initials: C
authors.lastname: Fellström
mesh_terms: D000818:Animals; D001315:Australia; D001483:Base Sequence; D017400:Brachyspira / Q000737:chemistry / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016000:Cluster Analysis; D004275:DNA, Ribosomal / Q000737:chemistry*; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D005060:Europe; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D016415:Sequence Alignment / Q000662:veterinary; D013145:Spirochaetales Infections / Q000382:microbiology / Q000662:veterinary*; D014481:United States
chemical_list: D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S