Trends towards lower antimicrobial susceptibility and characterization of acquired resistance among clinical isolates of Brachyspira hyodysenteriae in Spain.
The use of ELISAs for monitoring exposure of pig herds to Brachyspira hyodysenteriae.
Dissemination of clonal groups of Brachyspira hyodysenteriae amongst pig farms in Spain, and their relationships to isolates from other countries.
Antimicrobial susceptibility of porcine Brachyspira hyodysenteriae and Brachyspira pilosicoli isolated in Sweden between 1990 and 2010.
Swine dysentery: aetiology, pathogenicity, determinants of transmission and the fight against the disease.
Production and characterization of monoclonal antibodies against Serpulina hyodysenteriae and S. innocens and their use in serotyping.
(38/81)Murine monoclonal antibodies (MAbs) directed against serotypes 1, 2, 8, and 9 of Serpulina hyodysenteriae and strain B256 of Serpulina innocens were produced and characterized. A serological classification of 96 field strains of S. hyodysenteriae and 28 field strains of S. innocens isolated from pigs showing clinical signs of swine dysentery was performed by rapid dot enzyme-linked immunosorbent assay (ELISA) with the MAbs. The results indicated that the majority of the field strains of S. hyodysenteriae (69%) belonged to serotypes 8, 1, and 9, whereas only 31% of the S. innocens strains were recognized by MAb 9H7, indicating the presence of antigenic heterogeneity among S. innocens isolates. Rapid dot ELISA with type-specific MAbs was found to be specific, sensitive, and easy to perform and thus to be suitable for routine serotyping of S. hyodysenteriae and S. innocens isolates. This is the first report of MAbs being used for serotyping clinical isolates of S. hyodysenteriae and S. innocens. (+info)
Distribution of the smpA gene from Serpulina hyodysenteriae among intestinal spirochaetes.
(39/81)Forty intestinal spirochaete strains were investigated for nucleotide sequences related to the smpA locus from Serpulina hyodysenteriae by Southern hybridization of chromosomal DNA using the smpA locus from S. hyodysenteriae strain P18A as a probe and by PCR using primers internal to the smpA gene. The intensity of the hybridization signal at high stringency and positive PCR results suggested that 12 S. hyodysenteriae strains possessed a similar nucleotide sequence. PCR was negative for another 12 S. hyodysenteriae strains and the hybridization signal obtained from 11 of these was weak and one was negative. All S. hyodysenteriae strains hybridized under low stringency conditions. These results indicated that there is variation among the smpA loci of S. hyodysenteriae strains. Among seven strains of S. innocens, and the proposed species 'S. intermedius' and 'S. murdochii', hybridization was weak and no PCR products were obtained, suggesting that these species have sequences related to, but divergent from, the smpA sequences of strains of S. hyodysenteriae. Both gene probe hybridization and PCR analysis of nine strains of the proposed new genus 'Anguillina', including isolates from pigs and humans, gave negative results. (+info)
Characterization of Serpulina hyodysenteriae isolates of serotypes 8 and 9 from Quebec by restriction endonuclease fingerprinting and ribotyping.
(40/81)This study was undertaken to assess the discriminatory value of restriction endonuclease fingerprinting (REF) analysis and ribotyping of 21 Serpulina hyodysenteriae isolates of serotypes 8 and 9. For REF analysis, DNAs were digested with the BglII restriction enzyme and the resultant fragments were separated by polyacrylamide gel electrophoresis. For ribotyping, hybridization of BglII genomic fragments with a probe of rrnB operon using an Escherichia coli rDNA probe was performed on all isolates. Although many isolates shared a common pattern by BglII REF and BglII ribotyping analysis, differences among some S. hyodysenteriae isolates were observed. REF and ribotyping using BglII restriction enzyme, were not specific for serotypes. The predominance of an REF and a ribotype pattern among S. hyodysenteriae isolates from Quebec suggested that epidemiologically important S. hyodysenteriae types occur in different swine herds. (+info)