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D J Hampson - One of the best experts on this subject based on the ideXlab platform.
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Brachyspira catarrhinii sp nov an anaerobic intestinal spirochaete isolated from vervet monkeys may have been misidentified as Brachyspira aalborgi in previous studies
Anaerobe, 2019Co-Authors: Nyree D. Phillips, D J HampsonAbstract:Abstract To date nine species of anaerobic intestinal spirochaetes have been validly assigned to the genus Brachyspira. These include both pathogenic and non-pathogenic species. In the current study a genomic analysis of a novel spirochaete isolate was undertaken to determine whether it is a distinct species that previously has been misidentified as Brachyspira aalborgi. The genome of spirochaete strain Z12 isolated from the faeces of a vervet monkey was sequenced and compared to the genomes of the type strains of the nine assigned Brachyspira species. Genome to Genome Distance (GGD) values and Average Nucleotide Identity (ANI) values were determined. Single nucleotide polymorphisms (SNP) were used to create a phylogenetic tree to assess relatedness. The 16S rRNA gene sequences of the strains were aligned and the similarity amongst the Brachyspira species was recorded. Multilocus sequence typing (MLST) using five loci was conducted on Z12 and results compared with those for other Brachyspira isolates. Assembly of the Z12 sequences revealed a 2,629,108 bp genome with an average G + C content of 31.3%. The GGD, ANI, 16S rRNA gene sequence comparisons and the MLST results all indicated that Z12 represents a distinct species within the genus Brachyspira, with its nearest neighbour being B. aalborgi. Spirochaete strain Z12T was assigned as the type strain of a new species, Brachyspira catarrhinii sp. nov. The diagnostic PCR currently in use to detect B. aalborgi cross-reacts with Z12, but RFLP analysis of PCR product can be used to distinguish the two species. Previous reports of non-human primates being colonised by B. aalborgi based on PCR results may have been incorrect. The development of an improved diagnostic method will allow future studies on the distribution and possible clinical significance of these two anaerobic spirochaete species.
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antimicrobial resistance in Brachyspira an increasing problem for disease control
Veterinary Microbiology, 2019Co-Authors: D J Hampson, Darren J. Trott, Nyree D. Phillips, Kittitat Lugsomya, Sam AbrahamAbstract:Across all bacterial species the continuing reduction in susceptibility to antimicrobial agents is a critical and increasing threat for disease control. This mini-review outlines the extent of this problem amongst anaerobic intestinal spirochaetes of the genus Brachyspira, of which there are currently nine officially recognised species. These include some important pathogens that may cause colitis with diarrhoea and/or dysentery in various mammalian and avian species, but most notably in pigs and in adult chickens. The most economically significant pathogen is Brachyspira hyodysenteriae, the spirochaete which causes swine dysentery in countries throughout the world. Control of infections with Brachyspira species has long relied on the prophylactic or therapeutic use of antimicrobials, but increasingly strains with reduced susceptibility and sometimes multidrug resistance to previously effective antimicrobial agents are being encountered. In this mini-review we outline these problems and explain the extent and molecular basis of the emerging resistance. Future control will rely on developing and applying standardised methods for measuring antimicrobial susceptibility; improving surveillance of resistance using traditional phenotypic as well as genomic analysis of known resistance determinants; improving understanding of the molecular basis of resistance to different drug classes; improving farmer and veterinarian education about prudent antimicrobial use so as to reduce selective pressure on the emergence of resistance; and developing alternatives to antimicrobials as a means to control these infections.
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characterization and recognition of Brachyspira hampsonii sp nov a novel intestinal spirochete that is pathogenic to pigs
Journal of Clinical Microbiology, 2016Co-Authors: Nandita S Mirajkar, D J Hampson, Nyree D. Phillips, Connie J GebhartAbstract:Swine dysentery (SD) is a mucohemorrhagic colitis of swine classically caused by infection with the intestinal spirochete Brachyspira hyodysenteriae Since around 2007, cases of SD have occurred in North America associated with a different strongly beta-hemolytic spirochete that has been molecularly and phenotypically characterized and provisionally named "Brachyspira hampsonii." Despite increasing international interest, B. hampsonii is currently not recognized as a valid species. To support its recognition, we sequenced the genomes of strains NSH-16T, NSH-24, and P280/1, representing B. hampsonii genetic groups I, II, and III, respectively, and compared them with genomes of other valid Brachyspira species. The draft genome of strain NSH-16T has a DNA G+C content of 27.4% and an approximate size of 3.2 Mb. Genomic indices, including digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI), and average amino acid identity (AAI), clearly differentiated B. hampsonii from other recognized Brachyspira species. Although discriminated genotypically, the three genetic groups are phenotypically similar. By electron microscopy, cells of different strains of B. hampsonii measure 5 to 10 μm by 0.28 to 0.34 μm, with one or two flat curves, and have 10 to 14 periplasmic flagella inserted at each cell end. Using a comprehensive evaluation of genotypic (gene comparisons and multilocus sequence typing and analysis), genomic (dDDH, ANI, and AAI) and phenotypic (hemolysis, biochemical profiles, protein spectra, antibiogram, and pathogenicity) properties, we classify Brachyspira hampsonii sp. nov. as a unique species with genetically diverse yet phenotypically similar genomovars (I, II, and III). We designate the type strain NSH-16 (= ATCC BAA-2463 = NCTC 13792).
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Brachyspira hyodysenteriae isolated from apparently healthy pig herds following an evaluation of a prototype commercial serological elisa
Veterinary Microbiology, 2016Co-Authors: D J Hampson, Nyree D. Phillips, Patricia K HolyoakeAbstract:Swine dysentery (SD) is a disease mainly of grower/finisher pigs characterised by severe mucohaemorrhagic colitis. The classical aetiological agent is the anaerobic intestinal spirochaete Brachyspira hyodysenteriae, although “Brachyspira hampsonii” and Brachyspira suanatina also cause SD. This study reports on the unexpected isolation of B. hyodysenteriae from pigs in apparently healthy herds that gave positive reactions when tested with a prototype commercial serological ELISA for detecting herds infected with B. hyodysenteriae (Priocheck® Brachyspira porcine Ab ELISA). The ELISA was tested with sera collected at abattoirs from 1770 slaughtered pigs from 30 Australian herds, including 12 with a history of SD and18 that were considered by their consulting veterinarians to be healthy. The latter herds had no history of SD and did not routinely use antimicrobials that may have masked the disease. Based on the recommended ELISA cut-off value, 25 herds were recorded as showing evidence of infection, including 11 of 12 herds that were considered infected by the submitters and 14 of the 18 “healthy” herds. When faecal or colonic wall samples from 11 of the 14 “false positive” herds subsequently were culturing 6–24 months after the original ELISA testing was completed, different strains of B. hyodysenteriae were isolated from six herds, including a high-health status breeding herd. The existence of apparently healthy herds that are colonised by B. hyodysenteriae has major implications for the control of SD. Had the ELISA not been trialled it is unlikely that colonic samples from these herds would have been cultured and the colonisation identified.
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intestinal spirochaetes Brachyspira spp colonizing flocks of layer and breeder chickens in malaysia
Avian Pathology, 2014Co-Authors: Maswati Mat Amin, Nyree D. Phillips, I D Robertson, D J HampsonAbstract:Avian intestinal spirochaetosis causes problems including delayed onset of lay and wet litter in adult chickens, and results from colonization of the caecae/rectum with pathogenic intestinal spirochaetes (genus Brachyspira). Because avian intestinal spirochaetosis has not previously been studied in South East Asia, this investigation was undertaken in Malaysia. Faecal samples were collected from 25 farms and a questionnaire was administered. Brachyspira species were detected by polymerase chain reaction in 198 of 500 (39%) faecal samples from 20 (80%) farms, including 16 (94%) layer and four (50%) breeder farms. Pathogenic Brachyspira pilosicoli was identified in five (29%) layer and two (25%) breeder farms whilst pathogenic Brachyspira intermedia was detected in nine (53%) layer and one (12.5%) of the breeder farms. Twelve (80%) layer farms had egg production problems and 11 (92%) were positive for Brachyspira: three (25%) for B. pilosicoli and six (50%) for B. intermedia. Of three breeder farms with egg production problems, one was colonized with B. pilosicoli. Three of ten layer farms with wet litter were positive for B. pilosicoli and six for B. intermedia. Of four breeder farms with wet litter, one was colonized with B. pilosicoli and one with B. intermedia. No significant associations were found between colonization and reduced egg production or wet litter, perhaps because so many flocks were colonized. A significant association (P = 0.041) occurred between a high prevalence of colonization and faecal staining of eggs. There were significant positive associations between open-sided housing (P = 0.006), and flocks aged >40 weeks (P < 0.001) and colonization by pathogenic species.
Desiree S Jansson - One of the best experts on this subject based on the ideXlab platform.
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intestinal spirochaetes genus Brachyspira colonise wild birds in the southern atlantic region and antarctica
Infection ecology & epidemiology, 2015Co-Authors: Desiree S Jansson, Memoona Mushtaq, Karlerik Johansson, Jonas Bonnedahl, Jonas Waldenstrom, Dan I Andersson, Tina Broman, Charlotte Berg, Bjorn R OlsenAbstract:Introduction : The genus Brachyspira contains well-known enteric pathogens of veterinary significance, suggested agents of colonic disease in humans, and one potentially zoonotic agent. There are recent studies showing that Brachyspira are more widespread in the wildlife community than previously thought. There are no records of this genus in wildlife from the southern Atlantic region and Antarctica. Our aim was therefore, to determine whether intestinal spirochaetes of genus Brachyspira colonise marine and coastal birds in this region. Method : Faecal samples were collected from marine and coastal birds in the southern Atlantic region, including sub-Antarctic islands and Antarctica, in 2002, 2009, and 2012, with the aim to isolate and characterise zoonotic agents. In total, 205 samples from 11 bird species were selectively cultured for intestinal spirochaetes of genus Brachyspira . To identify isolates to species level, they were subjected to phenotyping, species-specific polymerase chain reactions, sequencing of partial 16S rRNA, NADH oxidase ( nox ), and tly A genes, and phylogenetic analysis. Antimicrobial susceptibility tests were performed. Results : Fourteen unique strains were obtained from 10 birds of three species: four snowy sheathbills ( Chionis albus ), three kelp geese ( Chloephaga hybrida subsp. malvinarum ), and three brown skua ( Stercorarius antarcticus subsp. lonnbergi ) sampled on the Falkland Islands, Tierra del Fuego in Argentina, South Georgia, South Shetland Islands, and the Antarctic Peninsula. Five Brachyspira strains were closely related to potentially enteropathogenic Brachyspira sp. of chickens: B . intermedia ( n= 2, from snowy sheathbills), and B . alvinipulli ( n= 3, from a kelp goose and two snowy sheathbills). Three strains from kelp geese were most similar to the presumed non-pathogenic species ‘ B. pulli ’ and B . murdochii , whereas the remaining six strains could not be attributed to currently known species. No isolates related to human strains were found. None of the tested strains showed decreased susceptibility to tiamulin, valnemulin, doxycycline, tylvalosin, lincomycin, or tylosin. Conclusions : This is the first report of intestinal spirochaetes from this region. Despite limitations of current diagnostic methods, our results, together with earlier studies, show that Brachyspira spp., including potentially pathogenic strains, occur globally among free-living avian hosts, and that this genus encompasses a higher degree of biodiversity than previously recognised. Keywords: Antarctica; antimicrobial susceptibility; Brachyspira; brown skua; kelp goose; intestinal spirochaete; phylogeny; snowy sheathbill; southern Atlantic region; sub-Antarctic islands (Published: 18 November 2015) Citation: Infection Ecology and Epidemiology 2015, 5: 29296 - http://dx.doi.org/10.3402/iee.v5.29296
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Brachyspira suanatina sp nov an enteropathogenic intestinal spirochaete isolated from pigs and mallards genomic and phenotypic characteristics
BMC Microbiology, 2015Co-Authors: Mamoona Mushtaq, T Råsbäck, Desiree S Jansson, Saima Zubair, Erik BongcamrudloffAbstract:The genus Brachyspira currently encompasses seven valid species that colonize the intestines of mammals and birds. In a previous study a group of strongly haemolytic isolates from pigs and mallards was provisionally described as a new species within genus Brachyspira, “B. suanatina”, and enteropathogenic properties were demonstrated in a porcine challenge model. In the current study characterization of B. suanatina was performed on the basis of cell morphology, growth characteristics, enzyme profiles, DNA-DNA hybridization (DDH) and whole genome comparisons. The draft genome sequence of B. suanatina strain AN4859/03 was determined and compared with the available genomes of all valid species of Brachyspira. According to morphological traits, growth characteristics and enzymatic profiles, B. suanatina was similar to the type strain of B. hyodysenteriae, but using the recommended threshold value of 70 % similarity by DDH it did not belong to any of the recognized Brachyspira species (range 16–64 % similarity). This was further supported by average nucleotide identity values. Phylogenetic analysis performed using housekeeping genes and core genomes of all valid Brachyspira sp. and “B. hampsonii” revealed that B. suanatina and B. intermedia formed a clade distinct from B. hyodysenteriae. By comparing the genomes of the three closely related species B. intermedia, B. hyodysenteriae and B. suanatina similar profiles of general genomic features and distribution of genes in different functional categories were obtained. However, the genome size of B. hyodysenteriae was smallest among the species, suggesting the possibility of reductive evolution in the divergence of this species. A bacteriophage region and a putative plasmid sequence were also found in the genome of B. suanatina strain AN4859/03. The results of our study suggest that despite being similar to B. hyodysenteriae phenotypically, B. suanatina should be regarded as a separate species based on its genetic characteristics. Based on characteristics presented in this report we propose that strains AN4859/03, AN1681:1/04, AN2384/04 and Dk12570-2 from pigs in Sweden and Denmark, and strains AN3949:2/02 and AN1418:2/01 isolated from mallards in Sweden, represent a unique species within genus Brachyspira. For this new species we propose the name B. suanatina for which the type strain is AN4859/03T (=ATCC® BAA-2592™ = DSM 100974T).
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phenotypic and genetic diversity among intestinal spirochaetes genus Brachyspira in free living wild mallards anas platyrhynchos sampled in southern sweden
Systematic and Applied Microbiology, 2011Co-Authors: Desiree S Jansson, Karlerik Johansson, M Persson, Ulla ZimmermanAbstract:Abstract Brachyspira spp. are anaerobic intestinal spirochaetes that colonize vertebrates. Some species cause enteric diseases in pigs, chickens and possibly in humans, whereas others display a commensual relationship with their hosts. The aims were to investigate the prevalence among colonized free-living wild mallards ( Anas platyrhynchos ) of three enteropathogenic Brachyspira spp., and to describe the biodiversity of Brachyspira spp. isolates. Isolates from 150 birds were screened by PCR for 3 pathogenic Brachyspira spp., and 35 isolates from 20 mallards, 4 pigs and 1 chicken were subjected to phenotypic tests, 9 diagnostic PCRs, sequencing of the 16S rRNA and NADH oxidase ( nox ) genes, phylogenetic analysis and nox gene restriction enzyme analysis in silico . Of the 150 birds, 47%, 33% and 11% were positive by PCR for Brachyspira pilosicoli , Brachyspira intermedia and Brachyspira hyodysenteriae , respectively. Thirty-one characterized isolates were provisionally identified as B . intermedia , Brachyspira alvinipulli , “ Brachyspira pulli ”, or B. pilosicoli , whereas 4 were of indeterminate species affiliation. Many isolates were phylogenetically related to isolates from livestock. Isolates identified by PCR as B . pilosicoli displayed particularly high biodiversity. Up to five different Brachyspira genotypes were found from the same bird. Sequencing of amplicons from isolates that displayed ambiguous results as judged from PCR and phenotyping showed that several diagnostic PCRs were non-specific. Nox gene restriction enzyme analysis in silico correctly identified 2 of 34 characterized isolates. A culture technique based on filtration that produced uncontaminated spirochaete isolates was described. The results show that mallard intestines support a high degree of biodiversity among Brachyspira spp.
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typing of Brachyspira spp from rodents pigs and chickens on swedish farms
Veterinary Microbiology, 2011Co-Authors: Annette Backhans, Desiree S Jansson, Anna Aspan, Claes FellströmAbstract:The aim of the current study was to look for evidence of possible cross-species transmission of Brachyspira species between rodents and farm animals. To do this, previously collected and characterised Brachyspira isolates from rodents, pigs and chickens on the same farms were analysed by random amplified polymorphic DNA (RAPD). Isolates with similar RAPD banding patterns were further typed by pulsed-field gel electrophoresis (PFGE). Identical isolates of Brachyspira pilosicoli, Brachyspira intermedia, Brachyspira murdochii and Brachyspira innocens from pigs and rodents and of B. murdochii from laying hens and rodents were found, indicating cross-species transmission at farm level. PFGE data from rodent isolates of Brachyspira hyodysenteriae were compared with PFGE data from previously typed field isolates of B. hyodysenteriae from pigs with swine dysentery and isolates from mallards (Anas platyrhynchos). Three of four isolates of B. hyodysenteriae from rodents were similar to porcine field isolates by PFGE. PCR analyses of the plasmid-encoded and potential virulence determinants rfb genes B, A, D and C showed that they were present in isolates of B. hyodysenteriae of porcine, mallard and rodent origin.
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complete genome sequence of Brachyspira intermedia reveals unique genomic features in Brachyspira species and phage mediated horizontal gene transfer
BMC Genomics, 2011Co-Authors: Therese Hafstrom, Desiree S Jansson, Bo SegermanAbstract:Brachyspira spp. colonize the intestines of some mammalian and avian species and show different degrees of enteropathogenicity. Brachyspira intermedia can cause production losses in chickens and strain PWS/AT now becomes the fourth genome to be completed in the genus Brachyspira. 15 classes of unique and shared genes were analyzed in B. intermedia, B. murdochii, B. hyodysenteriae and B. pilosicoli. The largest number of unique genes was found in B. intermedia and B. murdochii. This indicates the presence of larger pan-genomes. In general, hypothetical protein annotations are overrepresented among the unique genes. A 3.2 kb plasmid was found in B. intermedia strain PWS/AT. The plasmid was also present in the B. murdochii strain but not in nine other Brachyspira isolates. Within the Brachyspira genomes, genes had been translocated and also frequently switched between leading and lagging strands, a process that can be followed by different AT-skews in the third positions of synonymous codons. We also found evidence that bacteriophages were being remodeled and genes incorporated into them. The accessory gene pool shapes species-specific traits. It is also influenced by reductive genome evolution and horizontal gene transfer. Gene-transfer events can cross both species and genus boundaries and bacteriophages appear to play an important role in this process. A mechanism for horizontal gene transfer appears to be gene translocations leading to remodeling of bacteriophages in combination with broad tropism.
Karlerik Johansson - One of the best experts on this subject based on the ideXlab platform.
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intestinal spirochaetes genus Brachyspira colonise wild birds in the southern atlantic region and antarctica
Infection ecology & epidemiology, 2015Co-Authors: Desiree S Jansson, Memoona Mushtaq, Karlerik Johansson, Jonas Bonnedahl, Jonas Waldenstrom, Dan I Andersson, Tina Broman, Charlotte Berg, Bjorn R OlsenAbstract:Introduction : The genus Brachyspira contains well-known enteric pathogens of veterinary significance, suggested agents of colonic disease in humans, and one potentially zoonotic agent. There are recent studies showing that Brachyspira are more widespread in the wildlife community than previously thought. There are no records of this genus in wildlife from the southern Atlantic region and Antarctica. Our aim was therefore, to determine whether intestinal spirochaetes of genus Brachyspira colonise marine and coastal birds in this region. Method : Faecal samples were collected from marine and coastal birds in the southern Atlantic region, including sub-Antarctic islands and Antarctica, in 2002, 2009, and 2012, with the aim to isolate and characterise zoonotic agents. In total, 205 samples from 11 bird species were selectively cultured for intestinal spirochaetes of genus Brachyspira . To identify isolates to species level, they were subjected to phenotyping, species-specific polymerase chain reactions, sequencing of partial 16S rRNA, NADH oxidase ( nox ), and tly A genes, and phylogenetic analysis. Antimicrobial susceptibility tests were performed. Results : Fourteen unique strains were obtained from 10 birds of three species: four snowy sheathbills ( Chionis albus ), three kelp geese ( Chloephaga hybrida subsp. malvinarum ), and three brown skua ( Stercorarius antarcticus subsp. lonnbergi ) sampled on the Falkland Islands, Tierra del Fuego in Argentina, South Georgia, South Shetland Islands, and the Antarctic Peninsula. Five Brachyspira strains were closely related to potentially enteropathogenic Brachyspira sp. of chickens: B . intermedia ( n= 2, from snowy sheathbills), and B . alvinipulli ( n= 3, from a kelp goose and two snowy sheathbills). Three strains from kelp geese were most similar to the presumed non-pathogenic species ‘ B. pulli ’ and B . murdochii , whereas the remaining six strains could not be attributed to currently known species. No isolates related to human strains were found. None of the tested strains showed decreased susceptibility to tiamulin, valnemulin, doxycycline, tylvalosin, lincomycin, or tylosin. Conclusions : This is the first report of intestinal spirochaetes from this region. Despite limitations of current diagnostic methods, our results, together with earlier studies, show that Brachyspira spp., including potentially pathogenic strains, occur globally among free-living avian hosts, and that this genus encompasses a higher degree of biodiversity than previously recognised. Keywords: Antarctica; antimicrobial susceptibility; Brachyspira; brown skua; kelp goose; intestinal spirochaete; phylogeny; snowy sheathbill; southern Atlantic region; sub-Antarctic islands (Published: 18 November 2015) Citation: Infection Ecology and Epidemiology 2015, 5: 29296 - http://dx.doi.org/10.3402/iee.v5.29296
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phenotypic and genetic diversity among intestinal spirochaetes genus Brachyspira in free living wild mallards anas platyrhynchos sampled in southern sweden
Systematic and Applied Microbiology, 2011Co-Authors: Desiree S Jansson, Karlerik Johansson, M Persson, Ulla ZimmermanAbstract:Abstract Brachyspira spp. are anaerobic intestinal spirochaetes that colonize vertebrates. Some species cause enteric diseases in pigs, chickens and possibly in humans, whereas others display a commensual relationship with their hosts. The aims were to investigate the prevalence among colonized free-living wild mallards ( Anas platyrhynchos ) of three enteropathogenic Brachyspira spp., and to describe the biodiversity of Brachyspira spp. isolates. Isolates from 150 birds were screened by PCR for 3 pathogenic Brachyspira spp., and 35 isolates from 20 mallards, 4 pigs and 1 chicken were subjected to phenotypic tests, 9 diagnostic PCRs, sequencing of the 16S rRNA and NADH oxidase ( nox ) genes, phylogenetic analysis and nox gene restriction enzyme analysis in silico . Of the 150 birds, 47%, 33% and 11% were positive by PCR for Brachyspira pilosicoli , Brachyspira intermedia and Brachyspira hyodysenteriae , respectively. Thirty-one characterized isolates were provisionally identified as B . intermedia , Brachyspira alvinipulli , “ Brachyspira pulli ”, or B. pilosicoli , whereas 4 were of indeterminate species affiliation. Many isolates were phylogenetically related to isolates from livestock. Isolates identified by PCR as B . pilosicoli displayed particularly high biodiversity. Up to five different Brachyspira genotypes were found from the same bird. Sequencing of amplicons from isolates that displayed ambiguous results as judged from PCR and phenotyping showed that several diagnostic PCRs were non-specific. Nox gene restriction enzyme analysis in silico correctly identified 2 of 34 characterized isolates. A culture technique based on filtration that produced uncontaminated spirochaete isolates was described. The results show that mallard intestines support a high degree of biodiversity among Brachyspira spp.
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phenotypic and molecular characterization of Brachyspira spp isolated from laying hens in different housing systems
Veterinary Microbiology, 2008Co-Authors: Desiree S Jansson, T Råsbäck, Claes Fellström, Karlerik Johansson, Ivar Vagsholm, A Gunnarsson, F IngermaaAbstract:Abstract Several species of intestinal spirochaetes, Brachyspira (B.) alvinipulli, B. intermedia and B. pilosicoli, may cause reduced egg production and faecal staining of eggshells in chickens. The aim of this study was to characterize potentially pathogenic and presumably non-pathogenic Brachyspira spp. from commercial laying hens. Selective culture, phenotyping, PCR and 16S rRNA gene sequencing were used and clinical data were collected. Phenotypic profiles were obtained for 489 isolates and 351 isolates obtained after subculture, and 30 isolates were selected for molecular characterization. Seven isolates were positive by a B. intermedia-specific PCR based on the nox gene, and two were positive in a B. hyodysenteriae-specific 23S rRNA gene based PCR. By comparative phylogenetic analysis in combination with PCR and phenotyping, seven isolates were identified as B. intermedia, eight isolates as B. innocens, five as B. murdochii, and three isolates each as B. alvinipulli and “B. pulli”. The remaining four isolates could not be assigned to any presently recognized species. Co-infection with several species or genetic variants of Brachyspira spp. were detected in some flocks and samples, suggesting a high level of diversity. Organic flocks with access to outdoor areas were at higher risk (RR = 2.3; 95% CI 1.5–3.6) for being colonized than chickens in other housing systems. No significant differences between colonized and non-colonized flocks were found regarding clinical parameters, i.e. mortality, egg production, faecally contaminated eggshells, and wet litter. Our results show that a combination of traditional laboratory diagnostics, molecular tests and phylogeny is needed for identification of Brachyspira sp. from chickens.
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development of a multilocus sequence typing scheme for intestinal spirochaetes within the genus Brachyspira
Microbiology, 2007Co-Authors: T Råsbäck, Claes Fellström, Desiree S Jansson, Karlerik Johansson, Mohammad Yousef Alikhani, David S Dunn, D J HampsonAbstract:The purpose of this study was to evaluate a multilocus sequence typing (MLST) scheme for intestinal spirochaetes of the genus Brachyspira. Eight loci mainly coding for enzymes previously used in multilocus enzyme electrophoresis analysis of Brachyspira species were examined in 66 Brachyspira field isolates and type/reference strains. The isolates and strains were recovered from pigs, birds, dogs and a mouse and originated from seven European countries, the USA and Canada. Forty-six isolates represented recognized Brachyspira species and 20 represented provisionally designated species or isolates that have not been classified. Only two loci gave PCR products for all 66 strains and isolates, but amplicons for seven loci were obtained for 44 of the isolates. Sequences for each locus had a DNA allelic variation of 30-47 and an amino acid allelic variation of 14-47 that gave rise to the same number of sequence and amino acid types (58) for the strains and isolates studied. A population snapshot based on sequence and amino acid types showed a close phylogenetic relationship amongst the porcine isolates from the same geographical regions, and indicated a close evolutionary relationship between isolates recovered from pigs and mallards. A general concordance was obtained between the MLST groupings and classifications based on culture and biochemical tests, 16S rDNA sequence analysis and random amplified polymorphic DNA analysis. This is a first step towards establishing an MLST system for use in identifying Brachyspira species and determining relationships between individual strains and species in the genus.
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a novel enteropathogenic strongly haemolytic spirochaete isolated from pig and mallard provisionally designated Brachyspira suanatina sp nov
Environmental Microbiology, 2007Co-Authors: T Råsbäck, Desiree S Jansson, Karlerik Johansson, Claes FellströmAbstract:Summary Atypical, strongly haemolytic porcine isolates of intestinal spirochaetes differing genetically from Brachyspira hyodysenteriae were identified and characterized. The isolates were subjected to culture and biochemical tests, antimicrobial susceptibility testing and molecular analyses. None of four species-specific polymerase chain reaction systems targeting genes of B. hyodysenteriae gave a positive reaction. All the atypical porcine isolates were identical in their partial 16S rRNA and nox gene sequences with a previously described isolate from a mallard (Anas platyrhynchos), and differed only slightly from another mallard isolate. All these isolates were distinctly different from all currently recognized Brachyspira species. A challenge study was carried out using recently weaned pigs. Clinical signs and macroscopic changes consistent with swine dysentery were seen both in pigs given the atypical porcine isolate and in control pigs given the reference strain of B. hyodysenteriae (B204R). Pigs given the genetically similar isolate from a mallard became colonized and diarrhoea was observed. This is the first study indicating that Brachyspira isolates from mallard can infect pigs and induce diarrhoea. We propose that this atypical spirochaete genotype should be regarded as a new species within the genus Brachyspira, and be provisionally designated ‘Brachyspira suanatina’ sp. nov.
Claes Fellström - One of the best experts on this subject based on the ideXlab platform.
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typing of Brachyspira spp from rodents pigs and chickens on swedish farms
Veterinary Microbiology, 2011Co-Authors: Annette Backhans, Desiree S Jansson, Anna Aspan, Claes FellströmAbstract:The aim of the current study was to look for evidence of possible cross-species transmission of Brachyspira species between rodents and farm animals. To do this, previously collected and characterised Brachyspira isolates from rodents, pigs and chickens on the same farms were analysed by random amplified polymorphic DNA (RAPD). Isolates with similar RAPD banding patterns were further typed by pulsed-field gel electrophoresis (PFGE). Identical isolates of Brachyspira pilosicoli, Brachyspira intermedia, Brachyspira murdochii and Brachyspira innocens from pigs and rodents and of B. murdochii from laying hens and rodents were found, indicating cross-species transmission at farm level. PFGE data from rodent isolates of Brachyspira hyodysenteriae were compared with PFGE data from previously typed field isolates of B. hyodysenteriae from pigs with swine dysentery and isolates from mallards (Anas platyrhynchos). Three of four isolates of B. hyodysenteriae from rodents were similar to porcine field isolates by PFGE. PCR analyses of the plasmid-encoded and potential virulence determinants rfb genes B, A, D and C showed that they were present in isolates of B. hyodysenteriae of porcine, mallard and rodent origin.
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phenotypic and molecular characterization of Brachyspira spp isolated from laying hens in different housing systems
Veterinary Microbiology, 2008Co-Authors: Desiree S Jansson, T Råsbäck, Claes Fellström, Karlerik Johansson, Ivar Vagsholm, A Gunnarsson, F IngermaaAbstract:Abstract Several species of intestinal spirochaetes, Brachyspira (B.) alvinipulli, B. intermedia and B. pilosicoli, may cause reduced egg production and faecal staining of eggshells in chickens. The aim of this study was to characterize potentially pathogenic and presumably non-pathogenic Brachyspira spp. from commercial laying hens. Selective culture, phenotyping, PCR and 16S rRNA gene sequencing were used and clinical data were collected. Phenotypic profiles were obtained for 489 isolates and 351 isolates obtained after subculture, and 30 isolates were selected for molecular characterization. Seven isolates were positive by a B. intermedia-specific PCR based on the nox gene, and two were positive in a B. hyodysenteriae-specific 23S rRNA gene based PCR. By comparative phylogenetic analysis in combination with PCR and phenotyping, seven isolates were identified as B. intermedia, eight isolates as B. innocens, five as B. murdochii, and three isolates each as B. alvinipulli and “B. pulli”. The remaining four isolates could not be assigned to any presently recognized species. Co-infection with several species or genetic variants of Brachyspira spp. were detected in some flocks and samples, suggesting a high level of diversity. Organic flocks with access to outdoor areas were at higher risk (RR = 2.3; 95% CI 1.5–3.6) for being colonized than chickens in other housing systems. No significant differences between colonized and non-colonized flocks were found regarding clinical parameters, i.e. mortality, egg production, faecally contaminated eggshells, and wet litter. Our results show that a combination of traditional laboratory diagnostics, molecular tests and phylogeny is needed for identification of Brachyspira sp. from chickens.
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development of a multilocus sequence typing scheme for intestinal spirochaetes within the genus Brachyspira
Microbiology, 2007Co-Authors: T Råsbäck, Claes Fellström, Desiree S Jansson, Karlerik Johansson, Mohammad Yousef Alikhani, David S Dunn, D J HampsonAbstract:The purpose of this study was to evaluate a multilocus sequence typing (MLST) scheme for intestinal spirochaetes of the genus Brachyspira. Eight loci mainly coding for enzymes previously used in multilocus enzyme electrophoresis analysis of Brachyspira species were examined in 66 Brachyspira field isolates and type/reference strains. The isolates and strains were recovered from pigs, birds, dogs and a mouse and originated from seven European countries, the USA and Canada. Forty-six isolates represented recognized Brachyspira species and 20 represented provisionally designated species or isolates that have not been classified. Only two loci gave PCR products for all 66 strains and isolates, but amplicons for seven loci were obtained for 44 of the isolates. Sequences for each locus had a DNA allelic variation of 30-47 and an amino acid allelic variation of 14-47 that gave rise to the same number of sequence and amino acid types (58) for the strains and isolates studied. A population snapshot based on sequence and amino acid types showed a close phylogenetic relationship amongst the porcine isolates from the same geographical regions, and indicated a close evolutionary relationship between isolates recovered from pigs and mallards. A general concordance was obtained between the MLST groupings and classifications based on culture and biochemical tests, 16S rDNA sequence analysis and random amplified polymorphic DNA analysis. This is a first step towards establishing an MLST system for use in identifying Brachyspira species and determining relationships between individual strains and species in the genus.
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a novel enteropathogenic strongly haemolytic spirochaete isolated from pig and mallard provisionally designated Brachyspira suanatina sp nov
Environmental Microbiology, 2007Co-Authors: T Råsbäck, Desiree S Jansson, Karlerik Johansson, Claes FellströmAbstract:Summary Atypical, strongly haemolytic porcine isolates of intestinal spirochaetes differing genetically from Brachyspira hyodysenteriae were identified and characterized. The isolates were subjected to culture and biochemical tests, antimicrobial susceptibility testing and molecular analyses. None of four species-specific polymerase chain reaction systems targeting genes of B. hyodysenteriae gave a positive reaction. All the atypical porcine isolates were identical in their partial 16S rRNA and nox gene sequences with a previously described isolate from a mallard (Anas platyrhynchos), and differed only slightly from another mallard isolate. All these isolates were distinctly different from all currently recognized Brachyspira species. A challenge study was carried out using recently weaned pigs. Clinical signs and macroscopic changes consistent with swine dysentery were seen both in pigs given the atypical porcine isolate and in control pigs given the reference strain of B. hyodysenteriae (B204R). Pigs given the genetically similar isolate from a mallard became colonized and diarrhoea was observed. This is the first study indicating that Brachyspira isolates from mallard can infect pigs and induce diarrhoea. We propose that this atypical spirochaete genotype should be regarded as a new species within the genus Brachyspira, and be provisionally designated ‘Brachyspira suanatina’ sp. nov.
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Assessment of diagnostics and antimicrobial susceptibility testing of Brachyspira species using a ring test.
Veterinary microbiology, 2005Co-Authors: T Råsbäck, Claes Fellström, A Cizek, K Collin, Allan Gunnarsson, S M Jensen, A Mars, Bjarne Bergsjo, J. ThomsonAbstract:There is no ring test for quality assessment available in Europe for diagnostics and antimicrobial susceptibility testing of the fastidious, anaerobic bacteria of the genus Brachyspira. Therefore, an international ring test for Brachyspira spp. was performed once a year during 2002-2004. Two sets of coded samples were prepared and distributed on each occasion. One set comprised six swabs dipped in pig faeces spiked with Brachyspira spp. intended for diagnostics. The other set comprised two pure strains intended only for susceptibility testing. All methods used were in-house methods. The species used were Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira innocens, Brachyspira murdochii and Brachyspira intermedia. In most cases, the correct Brachyspira spp. were detected. However, the results showed that Brachyspira spp. could be difficult to identify, especially if two Brachyspira spp. were mixed or if the concentration of Brachyspira in faeces was low. Additionally, some laboratories reported Brachyspira growth in control samples that were not seeded with any spirochaetes. The lowest detection level was 10(2) bacteria/ml faeces for both B. hyodysenteriae and B. pilosicoli. The susceptibility tests performed showed that disc diffusion was not recommendable for Brachyspira spp. Extended antimicrobial dilution series gave most congruent results. The diversity of the results highlights the importance of ring tests for a high quality of diagnostics and antimicrobial susceptibility tests for Brachyspira spp. This is the first ring test described for Brachyspira spp.
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Brachyspira suanatina sp nov an enteropathogenic intestinal spirochaete isolated from pigs and mallards genomic and phenotypic characteristics
BMC Microbiology, 2015Co-Authors: Mamoona Mushtaq, T Råsbäck, Desiree S Jansson, Saima Zubair, Erik BongcamrudloffAbstract:The genus Brachyspira currently encompasses seven valid species that colonize the intestines of mammals and birds. In a previous study a group of strongly haemolytic isolates from pigs and mallards was provisionally described as a new species within genus Brachyspira, “B. suanatina”, and enteropathogenic properties were demonstrated in a porcine challenge model. In the current study characterization of B. suanatina was performed on the basis of cell morphology, growth characteristics, enzyme profiles, DNA-DNA hybridization (DDH) and whole genome comparisons. The draft genome sequence of B. suanatina strain AN4859/03 was determined and compared with the available genomes of all valid species of Brachyspira. According to morphological traits, growth characteristics and enzymatic profiles, B. suanatina was similar to the type strain of B. hyodysenteriae, but using the recommended threshold value of 70 % similarity by DDH it did not belong to any of the recognized Brachyspira species (range 16–64 % similarity). This was further supported by average nucleotide identity values. Phylogenetic analysis performed using housekeeping genes and core genomes of all valid Brachyspira sp. and “B. hampsonii” revealed that B. suanatina and B. intermedia formed a clade distinct from B. hyodysenteriae. By comparing the genomes of the three closely related species B. intermedia, B. hyodysenteriae and B. suanatina similar profiles of general genomic features and distribution of genes in different functional categories were obtained. However, the genome size of B. hyodysenteriae was smallest among the species, suggesting the possibility of reductive evolution in the divergence of this species. A bacteriophage region and a putative plasmid sequence were also found in the genome of B. suanatina strain AN4859/03. The results of our study suggest that despite being similar to B. hyodysenteriae phenotypically, B. suanatina should be regarded as a separate species based on its genetic characteristics. Based on characteristics presented in this report we propose that strains AN4859/03, AN1681:1/04, AN2384/04 and Dk12570-2 from pigs in Sweden and Denmark, and strains AN3949:2/02 and AN1418:2/01 isolated from mallards in Sweden, represent a unique species within genus Brachyspira. For this new species we propose the name B. suanatina for which the type strain is AN4859/03T (=ATCC® BAA-2592™ = DSM 100974T).
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phenotypic and molecular characterization of Brachyspira spp isolated from laying hens in different housing systems
Veterinary Microbiology, 2008Co-Authors: Desiree S Jansson, T Råsbäck, Claes Fellström, Karlerik Johansson, Ivar Vagsholm, A Gunnarsson, F IngermaaAbstract:Abstract Several species of intestinal spirochaetes, Brachyspira (B.) alvinipulli, B. intermedia and B. pilosicoli, may cause reduced egg production and faecal staining of eggshells in chickens. The aim of this study was to characterize potentially pathogenic and presumably non-pathogenic Brachyspira spp. from commercial laying hens. Selective culture, phenotyping, PCR and 16S rRNA gene sequencing were used and clinical data were collected. Phenotypic profiles were obtained for 489 isolates and 351 isolates obtained after subculture, and 30 isolates were selected for molecular characterization. Seven isolates were positive by a B. intermedia-specific PCR based on the nox gene, and two were positive in a B. hyodysenteriae-specific 23S rRNA gene based PCR. By comparative phylogenetic analysis in combination with PCR and phenotyping, seven isolates were identified as B. intermedia, eight isolates as B. innocens, five as B. murdochii, and three isolates each as B. alvinipulli and “B. pulli”. The remaining four isolates could not be assigned to any presently recognized species. Co-infection with several species or genetic variants of Brachyspira spp. were detected in some flocks and samples, suggesting a high level of diversity. Organic flocks with access to outdoor areas were at higher risk (RR = 2.3; 95% CI 1.5–3.6) for being colonized than chickens in other housing systems. No significant differences between colonized and non-colonized flocks were found regarding clinical parameters, i.e. mortality, egg production, faecally contaminated eggshells, and wet litter. Our results show that a combination of traditional laboratory diagnostics, molecular tests and phylogeny is needed for identification of Brachyspira sp. from chickens.
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development of a multilocus sequence typing scheme for intestinal spirochaetes within the genus Brachyspira
Microbiology, 2007Co-Authors: T Råsbäck, Claes Fellström, Desiree S Jansson, Karlerik Johansson, Mohammad Yousef Alikhani, David S Dunn, D J HampsonAbstract:The purpose of this study was to evaluate a multilocus sequence typing (MLST) scheme for intestinal spirochaetes of the genus Brachyspira. Eight loci mainly coding for enzymes previously used in multilocus enzyme electrophoresis analysis of Brachyspira species were examined in 66 Brachyspira field isolates and type/reference strains. The isolates and strains were recovered from pigs, birds, dogs and a mouse and originated from seven European countries, the USA and Canada. Forty-six isolates represented recognized Brachyspira species and 20 represented provisionally designated species or isolates that have not been classified. Only two loci gave PCR products for all 66 strains and isolates, but amplicons for seven loci were obtained for 44 of the isolates. Sequences for each locus had a DNA allelic variation of 30-47 and an amino acid allelic variation of 14-47 that gave rise to the same number of sequence and amino acid types (58) for the strains and isolates studied. A population snapshot based on sequence and amino acid types showed a close phylogenetic relationship amongst the porcine isolates from the same geographical regions, and indicated a close evolutionary relationship between isolates recovered from pigs and mallards. A general concordance was obtained between the MLST groupings and classifications based on culture and biochemical tests, 16S rDNA sequence analysis and random amplified polymorphic DNA analysis. This is a first step towards establishing an MLST system for use in identifying Brachyspira species and determining relationships between individual strains and species in the genus.
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a novel enteropathogenic strongly haemolytic spirochaete isolated from pig and mallard provisionally designated Brachyspira suanatina sp nov
Environmental Microbiology, 2007Co-Authors: T Råsbäck, Desiree S Jansson, Karlerik Johansson, Claes FellströmAbstract:Summary Atypical, strongly haemolytic porcine isolates of intestinal spirochaetes differing genetically from Brachyspira hyodysenteriae were identified and characterized. The isolates were subjected to culture and biochemical tests, antimicrobial susceptibility testing and molecular analyses. None of four species-specific polymerase chain reaction systems targeting genes of B. hyodysenteriae gave a positive reaction. All the atypical porcine isolates were identical in their partial 16S rRNA and nox gene sequences with a previously described isolate from a mallard (Anas platyrhynchos), and differed only slightly from another mallard isolate. All these isolates were distinctly different from all currently recognized Brachyspira species. A challenge study was carried out using recently weaned pigs. Clinical signs and macroscopic changes consistent with swine dysentery were seen both in pigs given the atypical porcine isolate and in control pigs given the reference strain of B. hyodysenteriae (B204R). Pigs given the genetically similar isolate from a mallard became colonized and diarrhoea was observed. This is the first study indicating that Brachyspira isolates from mallard can infect pigs and induce diarrhoea. We propose that this atypical spirochaete genotype should be regarded as a new species within the genus Brachyspira, and be provisionally designated ‘Brachyspira suanatina’ sp. nov.
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Assessment of diagnostics and antimicrobial susceptibility testing of Brachyspira species using a ring test.
Veterinary microbiology, 2005Co-Authors: T Råsbäck, Claes Fellström, A Cizek, K Collin, Allan Gunnarsson, S M Jensen, A Mars, Bjarne Bergsjo, J. ThomsonAbstract:There is no ring test for quality assessment available in Europe for diagnostics and antimicrobial susceptibility testing of the fastidious, anaerobic bacteria of the genus Brachyspira. Therefore, an international ring test for Brachyspira spp. was performed once a year during 2002-2004. Two sets of coded samples were prepared and distributed on each occasion. One set comprised six swabs dipped in pig faeces spiked with Brachyspira spp. intended for diagnostics. The other set comprised two pure strains intended only for susceptibility testing. All methods used were in-house methods. The species used were Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira innocens, Brachyspira murdochii and Brachyspira intermedia. In most cases, the correct Brachyspira spp. were detected. However, the results showed that Brachyspira spp. could be difficult to identify, especially if two Brachyspira spp. were mixed or if the concentration of Brachyspira in faeces was low. Additionally, some laboratories reported Brachyspira growth in control samples that were not seeded with any spirochaetes. The lowest detection level was 10(2) bacteria/ml faeces for both B. hyodysenteriae and B. pilosicoli. The susceptibility tests performed showed that disc diffusion was not recommendable for Brachyspira spp. Extended antimicrobial dilution series gave most congruent results. The diversity of the results highlights the importance of ring tests for a high quality of diagnostics and antimicrobial susceptibility tests for Brachyspira spp. This is the first ring test described for Brachyspira spp.