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Publication Date: 2012
Publication Name: BMC Genomics
Research Interests: Genomics, Bacteriophages, Genome Size, Horizontal Gene Transfer, Biological Sciences, and 16 moreHumans, High throughput screening, Birds, Animals, Genetic Association Studies, Genome, Phenotype, Sus, Whole Genome Sequencing, Genotype, Carbohydrate metabolism, Swine, Multienzyme complexes, Genetic variation, Host Specificity, and Genetic Analysis
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Publication Date: 2013
Publication Name: Research in Veterinary Science
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Publication Date: 2013
Publication Name: Gut Pathogens
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Publication Date: 2000
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The intestinal spirochete Brachyspira hyodysenteriae is an important pathogen in swine, causing mucohemorrhagic colitis in a disease known as swine dysentery. Based on the detection of significant linkage disequilibrium in multilocus... more
The intestinal spirochete Brachyspira hyodysenteriae is an important pathogen in swine, causing mucohemorrhagic colitis in a disease known as swine dysentery. Based on the detection of significant linkage disequilibrium in multilocus sequence data, the species is considered to be clonal. An analysis of the genome sequence of Western Australian B. hyodysenteriae strain WA1 has been published, and in the current study 19 further strains from countries around the world were sequenced with Illumina technology. The genomes were assembled and aligned to over 97.5% of the reference WA1 genome at a percentage sequence identity better than 80%. Strain regions not aligned to the reference ranged between 0.2 and 2.5%. Clustering of the strain genes found on average 2,354 (88%) core genes, 255 (8.6%) ancillary genes and 77 (2.9%) unique genes per strain. Depending on the strain the proportion of genes with 100% sequence identity to WA1 ranged from 85% to 20%. The result is a global comparative ...
Publication Date: 2015
Publication Name: PloS one
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Identification of the gene encoding BmpB, a 30 kDa outer envelope lipoprotein of Brachyspira (Serpulina) hyodysenteriae, and immunogenicity of recombinant BmpB in mice and pigsmore
by Tom La and David Hampson
A gene encoding a 30kDa outer envelope protein of the intestinal spirochaete Brachyspira (Serpulina) hyodysenteriae, was cloned and expressed in Escherichia coli strain XLOLR. Five phagemids containing DNA inserts encoding the protein... more
A gene encoding a 30kDa outer envelope protein of the intestinal spirochaete Brachyspira (Serpulina) hyodysenteriae, was cloned and expressed in Escherichia coli strain XLOLR. Five phagemids containing DNA inserts encoding the protein were established and one clone (pSHA) was sequenced. An 816bp hypothetical open reading frame (ORF) was identified, with a potential ribosome binding site (AGGAG), and putative -10 (TATAAT) and -35 (TTGAAA) promoter regions upstream from the ATG start of the ORF. A 12bp inverted repeat sequence, possibly serving as a transcription terminator, was identified downstream from the TAA stop codon. Analysis of the amino acid sequence identified a 19 residue hydrophobic signal peptide, incorporating a potential signal peptidase cleavage site and membrane lipoprotein lipid attachment site. Further analysis of the amino acid usage of this lipoprotein, designated BmpB, showed its possible outer membrane localisation. Comparison of the gene encoding the lipoprote...
Publication Date: 2000
Publication Name: Veterinary microbiology
Research Interests: Microbiology, Veterinary Microbiology, Western blotting, Escherichia coli, Mice, and 14 moreAnimals, Immunization, Monoclonal Antibodies, Lipoprotein(a), Swine, Lipoproteins, Feces, Amino Acid Profile, Veterinary Sciences, SIGNAL PEPTIDE, Amino Acid Sequence, Open Reading Frame, Recombinant Proteins, and Lipoprotein a
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Feral pigs are recognized as being a potential reservoir of pathogenic microorganisms that can infect domestic pigs and other species. The aim of this study was to investigate whether feral pigs in Western Australia were colonized by the... more
Feral pigs are recognized as being a potential reservoir of pathogenic microorganisms that can infect domestic pigs and other species. The aim of this study was to investigate whether feral pigs in Western Australia were colonized by the pathogenic enteric bacteria Lawsonia intracellularis, Brachyspira hyodysenteriae and/or Brachyspira pilosicoli. A total of 222 feral pigs from three study-populations were sampled. DNA was extracted from faeces or colonic contents and subjected to a previously described multiplex PCR for the three pathogenic bacterial species. A subset of 61 samples was cultured for Brachyspira species. A total of 42 (18.9%) of the 222 samples were PCR positive for L. intracellularis, 18 (8.1%) for B. hyodysenteriae and 1 (0.45%) for B. pilosicoli. Four samples were positive for both L. intracellularis and B. hyodysenteriae. Samples positive for the latter two pathogens were found in pigs from all three study-sites. A strongly haemolytic B. hyodysenteriae isolate wa...
Publication Date: Jan 2, 2009
Publication Name: Veterinary microbiology
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VSH-1 is an unusual prophage-like gene transfer agent (GTA) that has been described in the intestinal spirochaete Brachyspira hyodysenteriae. The GTA does not self-propagate, but it assembles into a virus-like particle and transfers... more
VSH-1 is an unusual prophage-like gene transfer agent (GTA) that has been described in the intestinal spirochaete Brachyspira hyodysenteriae. The GTA does not self-propagate, but it assembles into a virus-like particle and transfers random 7.5kb fragments of host DNA to other B. hyodysenteriae cells. To date the GTA VSH-1 has only been analysed in B. hyodysenteriae strain B204, in which 11 late function genes encoding prophage capsid, tail and lysis elements have been described. The aim of the current study was to look for these 11 genes in the near-complete genomes of B. hyodysenteriae WA1, B. pilosicoli 95/1000 and B. intermedia HB60. All 11 genes were found in the three new strains. The GTA genes in WA1 and 95/1000 were contiguous, whilst some of those in HB60 were not-although in all three strains some gene rearrangements were present. A new predicted open reading frame with potential functional importance was found in a consistent position associated with all four GTAs, located...
Publication Date: Jan 2, 2009
Publication Name: Veterinary microbiology
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PCR Amplification from Fixed Tissue Indicates Frequent Involvement of Brachyspira aalborgi in Human Intestinal Spirochetosismore
by Tom La and David Hampson
PCR procedures amplifying portions of the 16S rRNA and NADH oxidase genes of Brachyspira aalborgi and Serpulina pilosicoli were applied to DNA extracted from paraffin-embedded human colonic or rectal tissues from 30 Norwegian, Australian,... more
PCR procedures amplifying portions of the 16S rRNA and NADH oxidase genes of Brachyspira aalborgi and Serpulina pilosicoli were applied to DNA extracted from paraffin-embedded human colonic or rectal tissues from 30 Norwegian, Australian, and U.S. patients, 16 of whom had histologic evidence of intestinal spirochetosis (IS). B. aalborgi-specific sequences were identified by PCR in 10 of the IS patients
Publication Date: 1999
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Publication Date: 2011
Publication Name: Veterinary Microbiology
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Publication Date: 2009
Publication Name: Veterinary Microbiology
Research Interests: Microbiology, Veterinary Microbiology, Veterinary, Female, Animals, and 13 moreMolecular cloning, Swine, Feces, Veterinary Sciences, Genome sequence, Swine Diseases, Colon, Open Reading Frame, In Silico, Recombinant Protein, Recombinant Proteins, Enzyme Linked Immunosorbent Assay, and immunoglobulin G
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Avian intestinal spirochaetosis (AIS) is an infection of the caeca and/or colo-rectum of laying and meat breeder hens caused by anaerobic intestinal spirochaetes of the genus Brachyspira. AIS can result in a variety of symptoms, including... more
Avian intestinal spirochaetosis (AIS) is an infection of the caeca and/or colo-rectum of laying and meat breeder hens caused by anaerobic intestinal spirochaetes of the genus Brachyspira. AIS can result in a variety of symptoms, including delayed and/or reduced egg production, and increased faecal water content. The two most commonly reported Brachyspira species involved in AIS are Brachyspira pilosicoli and Brachyspira intermedia, and their detection and identification can be difficult and time consuming. In the current study a two-step nested duplex PCR (2S-N-D-PCR) was developed for the detection of these two species, using DNA extracted from washed chicken faeces. In the first step, a duplex PCR (D-PCR) amplifying Brachyspira genus-specific portions of the 16S rRNA and NADH oxidase (nox) genes was undertaken on the washed faeces. In the second step, a nested D-PCR was used that amplified species-specific portions of the 16S rRNA gene of B. pilosicoli and the nox gene of B. intermedia from the amplicons produced in the first step. The 2S-N-D-PCR was rapid and specific, and could be used to detect approximately 10(3) cells of each spirochaete species per gram of washed faeces. When tested on 882 chicken faecal samples from infected flocks, it detected 4-5% more positive faecal samples than did the standard method of selective anaerobic culture followed by individual species-specific PCR assays conducted on the growth on the primary plate. The application of this new technique should improve diagnostic capacity, and facilitate further studies on AIS.
Publication Date: 2006
Publication Name: Veterinary Microbiology
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Publication Date: 2004
Publication Name: Veterinary Microbiology
Research Interests: Microbiology, Veterinary Microbiology, Escherichia coli, Female, Animals, and 14 morePolymerase Chain Reaction, Vaccination, Lipoprotein(a), Swine, Lipoproteins, Feces, Veterinary Sciences, Swine Diseases, Colon, Dysentery, Recombinant Proteins, Enzyme Linked Immunosorbent Assay, Lipoprotein a, and Control Group
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A cross-sectional study was conducted on a commercial egg-producing farm with a history of wet litter. A total of 600 fresh caecal faecal samples were obtained from under cages of laying hens in three sheds each containing flocks of... more
A cross-sectional study was conducted on a commercial egg-producing farm with a history of wet litter. A total of 600 fresh caecal faecal samples were obtained from under cages of laying hens in three sheds each containing flocks of approximately 5400 hens. Samples were cultured for intestinal spirochaetes, and growth on the primary isolation plate was observed under a phase contrast microscope and subjected to PCRs specific for the intestinal spirochaetes Brachyspira intermedia and Brachyspira pilosicoli. Spirochaete isolates obtained in pure culture were assessed for their ability to cause haemolysis on blood agar and to produce indole, and were typed using pulsed field gel electrophoresis (PFGE). A 1250 base pair portion of the 16S rRNA gene of three B. intermedia and five unidentified isolates was sequenced, and the sequences compared with those of other Brachyspira species. Overall, 121 (20.2%) of the faecal samples contained spirochaetes as determined by growth on the plate and microscopy. Using PCR on the primary growth from these positive samples, 43 (7.2% overall) were shown to contain B. intermedia, 8 (1.3%) to contain B. pilosicoli, and 70 (11.7%) were PCR negative. Only 24 isolates of B. intermedia and five isolates of unknown species were obtained in pure culture. Comparative analysis of the 16S rRNA gene sequence identified the non-B. intermedia isolates as belonging to the proposed species "Brachyspira pulli". PFGE analysis of the B. intermedia strains identified them as having four major banding patterns. Individual patterns were found in hens from different flocks, suggesting cross-transmission of strains between flocks. No environmental sources of infection were identified. The youngest flock had a significantly lower level of colonisation with B. intermedia than the flock of intermediate age (P = 0.004), suggesting that following initial infection of individual young hens on this farm there was amplification and transmission of infection amongst members of the flock.
Publication Date: 2005
Publication Name: Veterinary Microbiology
Research Interests: Microbiology, Veterinary Microbiology, Phylogeny, Chicken, Female, and 17 moreAnimals, Polymerase Chain Reaction, Comparative Analysis, Incidence, Western Australia, Prevalence, POULTRY DISEASES, Chickens, Feces, Pulsed field gel electrophoresis (PFGE), Age Factors, Veterinary Sciences, Gel electrophoresis, Cross sectional Study, Cross Sectional Studies, Laying hen, and Phase Contrast
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The distribution of bmpB, a gene encoding a 29.7kDa lipoprotein with homology to MetQ, in Brachyspira hyodysenteriae and related speciesmore
by Tom La and David Hampson
The distribution of the bmpB gene encoding BmpB, a 29.7 kDa outer membrane lipoprotein of the intestinal spirochaete Brachyspira hyodysenteriae, was investigated. Using PCR, the gene was detected in all the 48 strains of B. hyodysenteriae... more
The distribution of the bmpB gene encoding BmpB, a 29.7 kDa outer membrane lipoprotein of the intestinal spirochaete Brachyspira hyodysenteriae, was investigated. Using PCR, the gene was detected in all the 48 strains of B. hyodysenteriae examined and in Brachyspira innocens strain B256T, but not in 11 other strains of B. innocens nor in 42 strains of other Brachyspira spp. The gene was sequenced from B. innocens strain B256T and from 11 strains of B. hyodysenteriae. The B. hyodysenteriae genes shared 97.9-100% nucleotide sequence similarity and had 97.5-99.5% similarity with the gene of B. innocens strain B256T. Southern hybridisation indicated that bmpB was present on a 1.9 kb HindIII fragment of the B. hyodysenteriae genome and on a 3.1 kb fragment of the B. innocens B256T genome. The B. innocens lipoprotein did not react in Western blots with monoclonal antibody BJL/SH1 that reacts with the B. hyodysenteriae lipoprotein. The difference in binding with the monoclonal antibody may reside in the replacement of a serine residue with a tyrosine residue at base position 210 in the lipoprotein from B. innocens B256T. Comparison of the BmpB amino acid sequence with sequences in the SWISS-PROT protein database indicated that it has 33.9-39.9% similarity with the d-methionine binding proteins (MetQ) of a number of pathogenic bacterial species. The bmpB gene was confirmed to be the same as a gene of B. hyodysenteriae that was recently designated "blpA".
Publication Date: 2005
Publication Name: Veterinary Microbiology
Research Interests: Microbiology, Veterinary Microbiology, Western blotting, Sequence alignment, Animals, and 14 morePolymerase Chain Reaction, Lipoprotein(a), Swine, Lipoproteins, Western blot, Multienzyme complexes, Veterinary Sciences, Monoclonal Antibody, Swine Diseases, Amino Acid Sequence, Base Sequence, Recombinant Proteins, Protein Binding, and Lipoprotein a
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Multilocus enzyme electrophoresis (MLEE) was used to identify, examine genetic relationships and look at disease associations of a collection of 53 intestinal spirochaete isolates previously recovered from the faeces of adult hens on 14... more
Multilocus enzyme electrophoresis (MLEE) was used to identify, examine genetic relationships and look at disease associations of a collection of 53 intestinal spirochaete isolates previously recovered from the faeces of adult hens on 14 farms in Qld, Australia. The MLEE results were compared with those previously obtained using species-specific PCR amplifications. The isolates were divided into five Brachyspira species groups by MLEE: Brachyspira murdochii (n=17), B. intermedia (n=15), B. pilosicoli (n=14), B. innocens (n=2) and "B. pulli" (n=1). Three new MLEE groups each containing single isolates also were identified. The results of the PCR assay for B. pilosicoli were concordant with the MLEE results, but the 23S rDNA-based PCR for B. intermedia had failed to detect 8 of the 15 isolates. The B. innocens/B. murdochii nox-based PCR had correctly identified all the isolates of B. murdochii, but did not identify either of the two B. innocens isolates. Using MLEE, isolates from two farms (14%) were identified as B. murdochii, whilst the pathogenic species B. intermedia and B. pilosicoli were present in hens from eight (57%) and five (36%) farms, respectively, and were identified together in four (29%) farms. All seven of the farms with production problems or wet litter were colonised with B. intermedia and/or B. pilosicoli. Six farms had multiple spirochaete isolates available for examination. Two broiler breeder farms both had five isolates of B. pilosicoli that shared the same MLEE electrophoretic type (ET), whilst one laying hen farm had three isolates of B. intermedia that all belonged to the same ET. Hence on each of these farms a predominant strain of a pathogenic species was present. On the other farms isolates of the same species were more diverse and belonged to different ETs. These results show that the epidemiology of intestinal spirochaetal infections in broiler breeder and laying hen flocks can vary considerably between farms, although the reasons for these differences were not established.
Publication Date: 2005
Publication Name: Veterinary Microbiology
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Influences of diet and vaccination on colonisation of pigs by the intestinal spirochaete Brachyspira (Serpulina) pilosicolimore
by Tom La and David Hampson
Publication Date: 2000
Publication Name: Veterinary Microbiology
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Publication Date: 2009
Publication Name: Veterinary Microbiology
Research Interests: Microbiology, Veterinary Microbiology, Standard Deviation, Animals, Lipoprotein(a), and 12 moreHealth Status, Swine, Lipoproteins, Veterinary Sciences, Swine Diseases, Sensitivity and Specificity, Dysentery, Recombinant Proteins, Reference Values, Enzyme Linked Immunosorbent Assay, Lipoprotein a, and Optical Density
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Avian intestinal spirochaetosis (AIS) is a disease complex affecting adult laying and breeding chickens associated with infection by anaerobic intestinal spirochaetes of the genus Brachyspira. Options for control of AIS are limited, as... more
Avian intestinal spirochaetosis (AIS) is a disease complex affecting adult laying and breeding chickens associated with infection by anaerobic intestinal spirochaetes of the genus Brachyspira. Options for control of AIS are limited, as few effective antimicrobial agents are registered for use in laying chickens. One of the two most commonly encountered pathogenic species in AIS is B. intermedia, and the aim of the current study was to determine whether a B. intermedia bacterin vaccine would help control AIS caused by this species. An autogenous bacterin was prepared from B. intermedia strain HB60 and given twice intramuscularly at a 3-week interval to 12 laying chickens housed in individual cages. Twelve non-vaccinated control chickens were placed in adjacent cages in the same room. Two weeks after the second vaccination all the chickens were experimentally challenged with B. intermedia HB60 by crop tube. Subsequently faeces were cultured for spirochaetes every 2-3 days, faecal water content and chicken weight were measured weekly, and egg numbers and weights were recorded daily. Serum was taken prior to both vaccinations, at the time of challenge and at euthanasia. The chickens were killed 6 weeks post-challenge. The vaccinated chickens showed seroconversion to the vaccine, but antibody levels declined significantly post-infection. In comparison, the non-vaccinated chickens showed seroconversion post-infection. The reason for the reduction in the antibody levels in the vaccinated chickens after infection was not explained. At some point all the chickens excreted spirochaetes in their faeces, and the duration of excretion was not different between vaccinated and non-vaccinated chickens. There were no differences in faecal water content, chicken weights, egg production, or gross and microscopic caecal lesions between vaccinated and non-vaccinated chickens. In conclusion, an autogenous bacterin vaccine did not prevent infection with B. intermedia in laying chickens.
Publication Date: 2009
Publication Name: Veterinary Microbiology
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The aims of this study were to use multilocus sequence typing (MLST) to (i) investigate the population structure, diversity and molecular epidemiology of the weakly haemolytic anaerobic intestinal spirochaete Brachyspira intermedia, and... more
The aims of this study were to use multilocus sequence typing (MLST) to (i) investigate the population structure, diversity and molecular epidemiology of the weakly haemolytic anaerobic intestinal spirochaete Brachyspira intermedia, and (ii) determine the relationship of the species to the other two indole-positive but strongly haemolytic Brachyspira species--B. hyodysenteriae and "B. suanatina". Seventy-seven B. intermedia isolates from pigs and chickens were analysed, with the nucleotide sequences of seven conserved genomic loci examined for each. B. intermedia was genetically diverse, with the 77 isolates being divided into 71 sequence types (STs) and 64 amino acid types (AATs). Many distinct groups of B. intermedia isolates were identified, with some isolates being separated from others by large genetic distances. Although both pig and chicken isolates were found in most groups, suggesting that cross-species transmission of such isolates may occur, some isolates from pigs were located in small groups that did not include chicken isolates, and vice versa. Eight clonal complexes (Cc) of STs were identified by e-Burst analysis. The Ccs contained between 2 and 5 STs, and between 2 and 9 isolates. Five Ccs contained multiple isolates from the same farms, collected at the same time, indicating the existence of ongoing minor genetic change amongst isolates at the farm level. On the other hand, isolates with quite different STs also were found amongst multiple isolates collected from some farms. By comparison with the much more restricted diversity observed for 111 isolates of B. hyodysenteriae, and 4 isolates of "B. suanatina", it is difficult to justify including all weakly haemolytic indole-positive Brachyspira isolates in the single species B. intermedia.
Publication Date: 2010
Publication Name: Veterinary Microbiology
Research Interests: Genetics, Microbiology, Veterinary Microbiology, Genetic Diversity, Molecular Epidemiology, and 13 morePhylogeny, Population structure, Animals, MLST, POULTRY DISEASES, Chickens, Swine, Genetic variation, Amino Acid Profile, Veterinary Sciences, Swine Diseases, Genetic distance, and Multilocus sequence typing
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The purpose of this study was to develop and apply a multilocus sequence typing (MLST) scheme to study the molecular epidemiology of Brachyspira hyodysenteriae, the aetiological agent of swine dysentery. Sequences of seven conserved... more
The purpose of this study was to develop and apply a multilocus sequence typing (MLST) scheme to study the molecular epidemiology of Brachyspira hyodysenteriae, the aetiological agent of swine dysentery. Sequences of seven conserved genomic loci were examined in 111 B. hyodysenteriae strains. Fifty-eight of these previously had been analysed by multilocus enzyme electrophoresis (MLEE), and for some the results of pulsed field gel electrophoresis (PFGE), restriction endonuclease analysis (REA) and/or serotyping also were available. The discriminatory power of these methods was compared. The strains were divided into 67 sequence types (STs) and 46 amino acid types (AATs) by MLST. The Index of Association value was significantly different from zero, indication that the population was clonal. Eleven clonal complexes (Cc) comprising between 2 and 10 STs were recognised. A population snapshot based on AATs placed 77.5% of the isolates from 30 of the AATs into one major cluster. The founder type AAT9 included 13 strains from nine STs that were isolated in Australia, Sweden, Germany and Belgium, including one from a mallard. The MLST results were generally comparable to those produced by MLEE. The MLST system had a similar discriminatory power to PFGE, but was more discriminatory than REA, MLEE or serotyping. MLST data provided evidence for likely transmission of strains between farms, but also for the occurrence of temporal "micro-evolution" of strains on individual farms. Overall, the MLST system proved to be a useful new tool for investigating the molecular epidemiology and diversity of B. hyodysenteriae.
Publication Date: 2009
Publication Name: Veterinary Microbiology
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Publication Date: 2011
Publication Name: British Journal of Nutrition
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Publication Date: 2010
Publication Name: PLoS ONE
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Genome Sequence of the Pathogenic Intestinal Spirochete Brachyspira hyodysenteriae Reveals Adaptations to Its Lifestyle in the Porcine Large Intestinemore
by David Hampson and Tom La
Not Available Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Return: Query Results Return items starting with number Query Form Database: Astronomy Physics... more
Not Available Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints
Publication Date: 2009
Publication Name: PLOS One
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The genus Brachyspira contains a number of species of commensal and pathogenic anaerobic intestinal spirochaetes that colonize human beings, animals and birds (Hampson & Stanton, 1997). With the rapidly growing interest in genome... more
The genus Brachyspira contains a number of species of commensal and pathogenic anaerobic intestinal spirochaetes that colonize human beings, animals and birds (Hampson & Stanton, 1997). With the rapidly growing interest in genome sequencing, proteomic ...
Publication Date: 2006
Publication Name: Microbiology (Reading, England)
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To develop an assay to simultaneously detect Lawsonia intracellularis, Brachyspira hyodysenteriae and Brachyspira pilosicoli in pig faeces. A multiplex-polymerase chain reaction (M-PCR) was designed to amplify a 655-base pair (bp) portion... more
To develop an assay to simultaneously detect Lawsonia intracellularis, Brachyspira hyodysenteriae and Brachyspira pilosicoli in pig faeces. A multiplex-polymerase chain reaction (M-PCR) was designed to amplify a 655-base pair (bp) portion of the L. intracellularis 16S rRNA gene, a 354-bp portion of the B. hyodysenteriae NADH oxidase gene, and a 823-bp portion of the B. pilosicoli 16S rRNA gene. Specificity was assessed using 80 strains of Brachyspira spp. and 30 other enteric bacteria. Bacterial DNA was extracted from faeces using the QIAamp DNA Stool Mini Kit. The M-PCR was tested in parallel with culture and/or PCR on 192 faecal samples from eight piggeries. Faeces also were seeded with known cell concentrations of the three pathogenic species, and the limits of detection of the M-PCR tested. The M-PCR was specific, with limits of detection of 10(2)-10(3) cells of the respective species per gram of faeces. The M-PCR is a rapid, sensitive and specific test for detecting three important enteric bacterial pathogens of pigs. The availability of a new diagnostic M-PCR will allow rapid detection and control of three key porcine enteric pathogens.
Publication Date: 2006
Publication Name: Letters in Applied Microbiology
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Publication Date: 2008
Publication Name: Journal of Medical Microbiology
Research Interests: Australia, Medical Microbiology, Papua New Guinea, Sequence Analysis, Biological Sciences, and 19 moreHumans, Sequence alignment, Escherichia coli, Female, Animals, Male, GC content, Enzyme, Molecular cloning, Anti-Bacterial Agents, New Guinea, Swine, Amino Acid Profile, Amino Acid Sequence, Base Sequence, Amino Acid Substitution Rates, Nucleotides, Beta Lactamases, and Medical
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Immunomagnetic separation of the intestinal spirochaetes Brachyspira pilosicoli and Brachyspira hyodysenteriae from porcine faecesmore
by Tom La and David Hampson
Publication Date: 2004
Publication Name: Journal of Medical Microbiology
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Publication Date: 2008
Publication Name: Journal of Clinical Microbiology
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Comparative Prevalences of Brachyspira aalborgi and Brachyspira (Serpulina) pilosicoli as Etiologic Agents of Histologically Identified Intestinal Spirochetosis in Australiamore
by Tom La and David Hampson
Publication Date: 2001
Publication Name: Journal of Clinical Microbiology
Research Interests: Australia, Papua New Guinea, Adolescent, Clinical Microbiology, Biological Sciences, and 16 moreHumans, Developing Country, DNA Extraction, Female, Clinical, Male, Polymerase Chain Reaction, Northern Territory, Western Australia, Aged, Prevalence, Intestines, Middle Aged, Human immunodeficiency virus, Adult, and Multienzyme complexes
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Publication Date: 2002
Publication Name: Journal of Clinical Microbiology
Research Interests: Microbiology, Environmental microbiology, Veterinary Microbiology, Medical Microbiology, Animal Welfare, and 36 moreInfectious Diseases, Multidisciplinary, United Kingdom, Clinical Microbiology, Biological Sciences, Dogs, Virulence, Phylogeny, Population structure, Molecular typing, Humans, Mice, Country of Origin, Birds, Animals, Pseudomonas aeruginosa, Intestines, Gram-negative bacteria, Natural Environment, Genotype, Swine, Genetic Recombination, Streptococcus suis, Virulence factor, Pseudomonas Aeruginosa, Veterinary Sciences, Genetic Relatedness, Gel electrophoresis, Acinetobacter baumannii, Swine Diseases, Pasteurella Multocida, Human Disease, Protective Antigen, Organic Compound, Serotyping, and Multilocus sequence typing
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Publication Date: 2010
Publication Name: Journal of Animal Science
Research Interests: Animal Science, Diet, Biological Sciences, Animal, Animal Feed, and 8 moreAnimals, Male, Dietary Supplements, Swine, Lupinus, Swine Diseases, Inulin, and Ileum
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Reclassification of Serpulina intermedia and Serpulina murdochii in the genus Brachyspira as Brachyspira intermedia comb. nov. and Brachyspira murdochii comb. novmore
by Tom La and David Hampson
Publication Date: 2006
Publication Name: International Journal of Systematic and Evolutionary Microbiology
Research Interests:
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by Tom La and David Hampson
Publication Date: 2006
Publication Name: Functional & Integrative Genomics
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by Tom La and David Hampson
Publication Date: 2001
Publication Name: FEMS Microbiology Letters
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Publication Date: 2010
Publication Name: BMC Microbiology
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This study aimed to evaluate the efficacy of some commonly used disinfectants in inactivating the pathogenic avian intestinal spirochaetes Brachyspira intermedia and Brachyspira pilosicoli, and to examine spirochaete survival in chicken... more
This study aimed to evaluate the efficacy of some commonly used disinfectants in inactivating the pathogenic avian intestinal spirochaetes Brachyspira intermedia and Brachyspira pilosicoli, and to examine spirochaete survival in chicken caecal faeces held at 4 degrees C, 25 degrees C or 37 degrees C. Six disinfectants were evaluated at their recommended working concentrations: alkaline salts, quaternary ammonium, iodine as an iodophor, chlorine from a chlorine-release agent, glutaraldehyde and hydrogen peroxide. All but alkaline salts inactivated two different concentrations of both spirochaete species in less than 1 min in the presence of organic matter. Both spirochaete species at three different cell concentrations survived in caecal faeces at 37 degrees C for between 2 and 17 h. B. intermedia tended to survive for longer than B. pilosicoli, but the maximum survival time for both species at 4 degrees C was only 72 to 84 h. Hence, avian intestinal spirochaetes are rapidly inactivated by several common disinfectants, and their survival time in chicken caecal faeces is much less than has been reported for porcine intestinal spirochaetes in porcine faeces. It should be relatively easy to break the cycle of infection between batches of laying birds by resting sheds for a few days, and by using disinfectants on any residual faecal matter.
Publication Date: 2003
Publication Name: Avian Pathology
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Publication Date: 2004
Publication Name: Avian Pathology
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This study investigated the influence of feeding diets based on cereals with different non-starch polysaccharide content on colonization with the intestinal spirochaete Brachyspira intermedia in experimentally infected laying hens. The... more
This study investigated the influence of feeding diets based on cereals with different non-starch polysaccharide content on colonization with the intestinal spirochaete Brachyspira intermedia in experimentally infected laying hens. The diets were based on wheat, barley, or barley and sorghum, all with or without supplementation with exogenous dietary enzymes. Six groups of 12 individually caged laying hens were fed the respective diets for 2 weeks, and then challenged at 20 weeks of age by crop tube with 10(8) to 10(9) colony forming units of active motile spirochaetes on five successive days. Eggs were collected daily. The birds were weighed weekly, and caecal faeces collected for assessment of water content. Every 3 to 4 days cloacal swabs were collected and subjected to culture and subsequent polymerase chain reaction for B. intermedia. The birds were killed at 27 weeks of age. Caecal contents were cultured for spirochaetes, and the viscosity of the ileal and rectal contents assessed. Dietary soluble non-starch polysaccharide content was not a consistent predictor of viscosity in the ileum, and the addition of enzymes did not significantly reduce the viscosity. A dietary influence on colonization was observed, with birds fed wheat having significantly more colonization than the birds fed the other diets. No significant association was found between either dietary soluble non-starch polysaccharide content or ileal viscosity and colonization with B. intermedia, as assessed by faecal excretion of the spirochaete. Dietary enzymes did not consistently or significantly reduce colonization. It was not established how wheat enhances colonization by B. intermedia, but the results suggest that wheat-based diets should be avoided in flocks infected with B. intermedia.
Publication Date: 2004
Publication Name: Avian Pathology
Research Interests:
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Anaerobic intestinal spirochetes (genus Brachyspira) include several species that are recognized as pathogens of poultry. Surveys undertaken in Europe and Australia have shown that layer and breeder flocks are often colonized by the... more
Anaerobic intestinal spirochetes (genus Brachyspira) include several species that are recognized as pathogens of poultry. Surveys undertaken in Europe and Australia have shown that layer and breeder flocks are often colonized by the pathogenic species Brachyspira intermedia and Brachyspira pilosicoli, but similar surveys have not been conducted in the United States. In the current study, DNA was extracted from fecal samples (n=50) collected from each of 21 flocks of laying hens >40 wk of age in Pennsylvania, and this material was tested for B. intermedia and B. pilosicoli using a duplex PCR. Negative samples also were tested using a Brachyspira genus-specific PCR. The consistency of the feces was observed, and manure handling systems and medication histories were recorded. Brachyspira intermedia was detected in 662 (63.1%) samples from 17 (81%) flocks, with a within-flock prevalence of 10%-100%. Brachyspira pilosicoli was detected in 112 (10.7%) samples from 5 flocks (23.8%), with a within-flock prevalence of 8%-82%. Four of the flocks had both pathogenic species present, three had no pathogenic species detected, and two had no Brachyspira species detected. Nine flocks had many fecal samples with a wet appearance and/or a caramel color, and all of these were colonized with one or the other of the two pathogenic species. Nine of 12 flocks with manure that was mainly dry also were colonized. Differences in colonization rates between flocks with or without wet manure were not significant. Colonization with pathogenic Brachyspira species, and particularly B. intermedia, occurs very commonly in layer flocks >40 wk of age in Pennsylvania. The significance of this high rate of colonization requires further investigation.
Publication Date: 2009
Publication Name: Avian Diseases
Research Interests:
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Pigs are colonized by two pathogenic species of anaerobic intestinal spirochetes, Brachyspira hyodysenteriae and B. pilosi- coli. B. hyodysenteriae causes swine dysentery, a severe muco- hemorrhagic diarrheal disease (10), while B.... more
Pigs are colonized by two pathogenic species of anaerobic intestinal spirochetes, Brachyspira hyodysenteriae and B. pilosi- coli. B. hyodysenteriae causes swine dysentery, a severe muco- hemorrhagic diarrheal disease (10), while B. pilosicoli causes porcine intestinal spirochetosis, a milder colitis that also occurs in other host species (9). Because of the economic impact of these diseases on pig production, rapid diagnostic