The Experts below are selected from a list of 3123 Experts worldwide ranked by ideXlab platform
Johan Höglund - One of the best experts on this subject based on the ideXlab platform.
-
An assessment of the use of cox1 and cox3 mitochondrial genetic markers for the identification of Dictyocaulus spp. (Nematoda: Trichostrongyloidea) in wild ruminants
Parasitology research, 2018Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Johan HöglundAbstract:Lungworms of the genus Dictyocaulus Railliet and Henry, 1907 (Nematoda: Trichostrongyloidea) are the causative agents of parasitic bronchitis (dictyocaulosis, husk) of various ungulate hosts, including domestic and wild ruminants. Correct diagnosis of lungworm species and a better understanding of the transmission patterns of Dictyocaulus spp. are crucial in minimising the risk of its cross transmission between wildlife and livestock, and for the control of dictyocaulosis. The study was conducted on large lungworms collected from European bison, roe deer and red deer. The study resulted in 14 sequences of the partial cox1 region of Dictyocaulus spp. and 10 novel DNA sequences of partial cox3 region, including the first available mt cox3 sequence, of the roe deer lungworm (D. capreolus). The European bison was infected with bison genotype of D. viviparus, whereas red deer and roe deer were infected with D. cervi and D. capreolus respectively. The current study revealed that the cox3 nucleotide sequences of D. capreolus and D. viviparus were 100% homologous to each other. Our findings indicate that the mt cox3 gene does not serve as an efficient mt marker for systematic, population genetic or molecular epidemiological studies of Dictyocaulus lungworms.
-
Interrelationships of Dictyocaulus spp. in Wild Ruminants with Morphological Description of Dictyocaulus cervi n. sp. (Nematoda: Trichostrongyloidea) from Red Deer, Cervus elaphus
The Journal of parasitology, 2017Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Aleksander W. Demiaszkiewicz, Johan HöglundAbstract:Lungworms from the genus Dictyocaulus cause parasitic bronchitis (dictyocaulosis) characterized by coughing and severe lung pathology in both domestic and wild ruminants. In this study we investigated the interrelationships of Dictyocaulus spp. from European bison (Bison bonasus L.), roe deer (Capreolus capreolus), and red deer (Cervus elaphus) by nucleotide sequence analysis spanning the 18S RNA gene (small subunit [SSU]) and internal transcribed spacer 2 (ITS2) regions of the ribosomal gene array as well as the mitochondrial cytochrome c oxidase subunit 1 (cox1). Molecular analyses of sequence data obtained partly with novel primers from between 10 and 50 specimens from each host were carried out. Bayesian inference analysis revealed that each host species was infected with different genotypes. Analysis of cox1 sequence data showed a diverse genetic background and high evolutionary potential of Dictyocaulus taxa. Data from lungworms of European bison revealed a distinct genotype of Dictyocaulus viviparus, whereas Dictyocaulus capreolus was only found in roe deer. In contrast, red deer were infected with a taxon with unique SSU, ITS2, and cox1 sequences. These results indicate the occurrence of a novel genotype from red deer, which differs significantly from the National Center for Biotechnology Information reference sequence of Dictyocaulus eckerti. The molecular evidence was consistent with a morphological study with description and imaging of Dictyocaulus cervi n. sp. recovered from red deer. Dictyocaulus cervi n. sp. can be distinguished from D. eckerti on the basis of the absence of cervical papillae, the occurrence of a single ring of 4 symmetrical submedian cephalic papillae, length of the tail in females, morphometry of the female reproductive system, and measurements of gubernacula in males. In conclusion, our findings further strengthen the idea that the genetic complexity and diversity among Dictyocaulus lungworms infecting wildlife ruminants is larger than previously believed and warrants further investigation.
-
Development of a multiplex PCR for identification of Dictyocaulus lungworms in domestic and wild ruminants.
Parasitology research, 2015Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Johan HöglundAbstract:Dictyocaulus lungworms are the causative agents of parasitic bronchitis (dictyocaulosis) characterised by coughing and severe lung pathology in domestic and wild ruminants. The objective of this study was to design a simple molecular test that could detect of lungworm DNA from both adult and larval lungworms and could distinguish between the most common Dictyocaulus species found in cattle and in some species of wild ruminants. A multiplex PCR test with four novel primers targeting species-specific regions of the second internal transcribed spacer (ITS2) was designed based on our own sequence data as well as on available sequence information in GenBank. After PCR amplification of lungworms from European bison (Bison bonasus), cattle (Bos taurus), moose (Alces alces), red deer (Cervus elaphus) and roe deer (Capreolus capreolus), products were analysed with gel electrophoresis. This resulted in three specific bands of different size depending on the species analysed. Dictyocaulus viviparus collected from cattle or European bison resulted in a ca. 560 bp band, D. capreolus collected from roe deer produced a band ca. 400 bp and the longest DNA band (ca. 660 bp) was obtained with DNA from Dictyocaulus sp. collected from red deer and moose. Dictyocaulus eckerti bands with expected size of 714 bp were not observed in our study. The multiplex method produced consistent results with samples from both Sweden and Poland and overcame the limitations of traditional techniques based on differences in morphological features of parasites at different life stages.
-
Assessment of the genetic relationship between Dictyocaulus species from Bos taurus and Cervus elaphus using complete mitochondrial genomic datasets.
Parasites & vectors, 2012Co-Authors: Robin B Gasser, Abdul Jabbar, Namitha Mohandas, Johan Höglund, Ross S. Hall, D. Timothy J. Littlewood, Aaron R. JexAbstract:Background Dictyocaulus species are strongylid nematodes of major veterinary significance in ruminants, such as cattle and cervids, and cause serious bronchitis or pneumonia (dictyocaulosis or “husk”). There has been ongoing controversy surrounding the validity of some Dictyocaulus species and their host specificity. Here, we sequenced and characterized the mitochondrial (mt) genomes of Dictyocaulus viviparus (from Bos taurus) with Dictyocaulus sp. cf. eckerti from red deer (Cervus elaphus), used mt datasets to assess the genetic relationship between these and related parasites, and predicted markers for future population genetic or molecular epidemiological studies.
-
Assessment of the genetic relationship between Dictyocaulus species from Bos taurus and Cervus elaphus using complete mitochondrial genomic datasets
Parasites & Vectors, 2012Co-Authors: Robin B Gasser, Abdul Jabbar, Namitha Mohandas, Johan Höglund, Ross S. Hall, D. Timothy J. Littlewood, Aaron R. JexAbstract:Background Dictyocaulus species are strongylid nematodes of major veterinary significance in ruminants, such as cattle and cervids, and cause serious bronchitis or pneumonia (dictyocaulosis or “husk”). There has been ongoing controversy surrounding the validity of some Dictyocaulus species and their host specificity. Here, we sequenced and characterized the mitochondrial (mt) genomes of Dictyocaulus viviparus (from Bos taurus ) with Dictyocaulus sp. cf. eckerti from red deer ( Cervus elaphus ), used mt datasets to assess the genetic relationship between these and related parasites, and predicted markers for future population genetic or molecular epidemiological studies. Methods The mt genomes were amplified from single adult males of D. viviparus and Dictyocaulus sp. cf. eckerti (from red deer) by long-PCR, sequenced using 454-technology and annotated using bioinformatic tools. Amino acid sequences inferred from individual genes of each of the two mt genomes were compared, concatenated and subjected to phylogenetic analysis using Bayesian inference (BI), also employing data for other strongylids for comparative purposes. Results The circular mt genomes were 13,310 bp ( D. viviparus ) and 13,296 bp ( Dictyocaulus sp. cf. eckerti ) in size, and each contained 12 protein-encoding, 22 transfer RNA and 2 ribosomal RNA genes, consistent with other strongylid nematodes sequenced to date. Sliding window analysis identified genes with high or low levels of nucleotide diversity between the mt genomes. At the predicted mt proteomic level, there was an overall sequence difference of 34.5% between D. viviparus and Dictyocaulus sp. cf. eckerti , and amino acid sequence variation within each species was usually much lower than differences between species. Phylogenetic analysis of the concatenated amino acid sequence data for all 12 mt proteins showed that both D. viviparus and Dictyocaulus sp. cf. eckerti were closely related, and grouped to the exclusion of selected members of the superfamilies Metastrongyloidea, Trichostrongyloidea, Ancylostomatoidea and Strongyloidea. Conclusions Consistent with previous findings for nuclear ribosomal DNA sequence data, the present analyses indicate that Dictyocaulus sp. cf. eckerti (red deer) and D. viviparus are separate species. Barcodes in the two mt genomes and proteomes should serve as markers for future studies of the population genetics and/or epidemiology of these and related species of Dictyocaulus .
Anna M. Pyziel - One of the best experts on this subject based on the ideXlab platform.
-
First report of a newly-described lungworm, Dictyocaulus cervi (Nematoda: Trichostrongyloidea), in moose (Alces alces) in central Europe
International journal for parasitology. Parasites and wildlife, 2020Co-Authors: Katarzyna Filip-hutsch, Aleksander W. Demiaszkiewicz, Anita Chęcińska, Tomasz Hutsch, Michał Czopowicz, Anna M. PyzielAbstract:Abstract Lungworms from the genus Dictyocaulus are the causative agents of verminous pneumonia in domestic and wild ungulates. Recently, in 2017, a new species was isolated from red deer and described as Dictyocaulus cervi; however, little is known about its epidemiology and pathogenicity in other cervids. The aim of our study was to determine the extent of infection with Dictyocaulus nematodes in the moose population in Poland. Parasitological necropsies were performed in 18 moose and 249 faecal samples were analysed. A combination of multiplex PCR and analysis of the partial SSU, cox1 and cyt B regions revealed the presence of D. cervi infection in two of the necropsied moose. Histopathological examinations revealed changes, including multiple cross sections of larvae of nematodes in alveoli, massive pulmonary fibrosis, mononuclear cell infiltration and diffuse alveolar damage in the lungs of four animals. The lesions were more pronounced when adult Dictyocaulus nematodes were present in the bronchi and bronchioles. Some of the observed pathological changes could be attributed to co-infection by nematodes of the Protostrongylidae, whose larvae were found in all four animals with lung pathologies. In the faeces, Dictyocaulus sp. larvae only occurred together with Protostrongylidae larvae; in addition, higher numbers of Protostrongylidae larvae were excreted in the faeces of animals with dictyocaulosis. The present study is the first report of the presence of D. cervi in moose, and demonstrates the value of multiplex PCR in the identification of Dictyocaulus nematodes. Our findings indicate that co-infections with multiple species of lung nematodes in moose may be commonplace, and this should be considered as a factor aggravating the course of parasitosis.
-
Pathological lesions in the lungs of red deer Cervus elaphus (L.) induced by a newly-described Dictyocaulus cervi (Nematoda: Trichostrongyloidea).
Veterinary parasitology, 2018Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Aleksander W. Demiaszkiewicz, Izabella Dolka, Joanna Werszko, Żaneta Steiner-bogdaszewska, Jan Wiśniewski, Krzysztof AnuszAbstract:The large lungworms of the genus Dictyocaulus are causative agents of parasitic bronchitis in various ungulate hosts, including red deer. Recently, the red deer-derived lungworm D. cervi was described and separated from D. eckerti. Little is known of the transmission patterns, epidemiology, geographical distribution and pathogenicity of D. cervi. Histological examinations were performed on 22 formalin-fixed lung tissue samples of hunted red deer. Exclusively, D. cervi adults were derived from 15 red deer and confirmed molecularly (GenBank accession: MH183394). Dictyocaulus cervi infection was associated with various degrees of lung pathology, including interstitial pneumonia, bronchitis and bronchiolitis with an influx of eosinophils, lymphocytes, plasma cells and macrophages; massive hyperplasia of lymphoid follicles within bronchiolar tissue, and hyperplasia of the bronchial and bronchiolar epithelium. Furthermore, emphysema, atelectasis and lung tissue congestion were noted. Interestingly, interstitial and subpleural fibrosis was seen in adult Dictyocaulus-negative samples, suggesting either a prepatent phase of Dictyocaulus infection or infection/coinfection with protostrongylid nematodes.
-
An assessment of the use of cox1 and cox3 mitochondrial genetic markers for the identification of Dictyocaulus spp. (Nematoda: Trichostrongyloidea) in wild ruminants
Parasitology research, 2018Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Johan HöglundAbstract:Lungworms of the genus Dictyocaulus Railliet and Henry, 1907 (Nematoda: Trichostrongyloidea) are the causative agents of parasitic bronchitis (dictyocaulosis, husk) of various ungulate hosts, including domestic and wild ruminants. Correct diagnosis of lungworm species and a better understanding of the transmission patterns of Dictyocaulus spp. are crucial in minimising the risk of its cross transmission between wildlife and livestock, and for the control of dictyocaulosis. The study was conducted on large lungworms collected from European bison, roe deer and red deer. The study resulted in 14 sequences of the partial cox1 region of Dictyocaulus spp. and 10 novel DNA sequences of partial cox3 region, including the first available mt cox3 sequence, of the roe deer lungworm (D. capreolus). The European bison was infected with bison genotype of D. viviparus, whereas red deer and roe deer were infected with D. cervi and D. capreolus respectively. The current study revealed that the cox3 nucleotide sequences of D. capreolus and D. viviparus were 100% homologous to each other. Our findings indicate that the mt cox3 gene does not serve as an efficient mt marker for systematic, population genetic or molecular epidemiological studies of Dictyocaulus lungworms.
-
Interrelationships of Dictyocaulus spp. in Wild Ruminants with Morphological Description of Dictyocaulus cervi n. sp. (Nematoda: Trichostrongyloidea) from Red Deer, Cervus elaphus
The Journal of parasitology, 2017Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Aleksander W. Demiaszkiewicz, Johan HöglundAbstract:Lungworms from the genus Dictyocaulus cause parasitic bronchitis (dictyocaulosis) characterized by coughing and severe lung pathology in both domestic and wild ruminants. In this study we investigated the interrelationships of Dictyocaulus spp. from European bison (Bison bonasus L.), roe deer (Capreolus capreolus), and red deer (Cervus elaphus) by nucleotide sequence analysis spanning the 18S RNA gene (small subunit [SSU]) and internal transcribed spacer 2 (ITS2) regions of the ribosomal gene array as well as the mitochondrial cytochrome c oxidase subunit 1 (cox1). Molecular analyses of sequence data obtained partly with novel primers from between 10 and 50 specimens from each host were carried out. Bayesian inference analysis revealed that each host species was infected with different genotypes. Analysis of cox1 sequence data showed a diverse genetic background and high evolutionary potential of Dictyocaulus taxa. Data from lungworms of European bison revealed a distinct genotype of Dictyocaulus viviparus, whereas Dictyocaulus capreolus was only found in roe deer. In contrast, red deer were infected with a taxon with unique SSU, ITS2, and cox1 sequences. These results indicate the occurrence of a novel genotype from red deer, which differs significantly from the National Center for Biotechnology Information reference sequence of Dictyocaulus eckerti. The molecular evidence was consistent with a morphological study with description and imaging of Dictyocaulus cervi n. sp. recovered from red deer. Dictyocaulus cervi n. sp. can be distinguished from D. eckerti on the basis of the absence of cervical papillae, the occurrence of a single ring of 4 symmetrical submedian cephalic papillae, length of the tail in females, morphometry of the female reproductive system, and measurements of gubernacula in males. In conclusion, our findings further strengthen the idea that the genetic complexity and diversity among Dictyocaulus lungworms infecting wildlife ruminants is larger than previously believed and warrants further investigation.
-
Development of a multiplex PCR for identification of Dictyocaulus lungworms in domestic and wild ruminants.
Parasitology research, 2015Co-Authors: Anna M. Pyziel, Zdzisław Laskowski, Johan HöglundAbstract:Dictyocaulus lungworms are the causative agents of parasitic bronchitis (dictyocaulosis) characterised by coughing and severe lung pathology in domestic and wild ruminants. The objective of this study was to design a simple molecular test that could detect of lungworm DNA from both adult and larval lungworms and could distinguish between the most common Dictyocaulus species found in cattle and in some species of wild ruminants. A multiplex PCR test with four novel primers targeting species-specific regions of the second internal transcribed spacer (ITS2) was designed based on our own sequence data as well as on available sequence information in GenBank. After PCR amplification of lungworms from European bison (Bison bonasus), cattle (Bos taurus), moose (Alces alces), red deer (Cervus elaphus) and roe deer (Capreolus capreolus), products were analysed with gel electrophoresis. This resulted in three specific bands of different size depending on the species analysed. Dictyocaulus viviparus collected from cattle or European bison resulted in a ca. 560 bp band, D. capreolus collected from roe deer produced a band ca. 400 bp and the longest DNA band (ca. 660 bp) was obtained with DNA from Dictyocaulus sp. collected from red deer and moose. Dictyocaulus eckerti bands with expected size of 714 bp were not observed in our study. The multiplex method produced consistent results with samples from both Sweden and Poland and overcame the limitations of traditional techniques based on differences in morphological features of parasites at different life stages.
Jens G. Mattsson - One of the best experts on this subject based on the ideXlab platform.
-
Limited sequence variation in the major sperm protein 1 (MSP) gene within populations and species of the genus Dictyocaulus (Nematoda)
Parasitology Research, 2008Co-Authors: Johan Höglund, Annie Engström, David A. Morrison, Anna Mineur, Jens G. MattssonAbstract:Populations of the bovine lungworm, Dictyocaulus viviparus , are genetically structured based on variation in mtDNA and AFLP data. Our aim was to investigate if this genetic variability also is reflected in a protein recognized by the host immune system. We focused on the major sperm protein (MSP), a small and abundant protein used in diagnostic immunoassays, which has been shown to be variable in some nematodes but not others. MSP was sequenced using worm DNA from eight adult worms from each of nine populations whose genetic structure previously had been quantified. For comparison, we also analyzed MSP sequences of the closely related Dictyocaulus eckerti and Dictyocaulus capreolus and from nematodes with sequences deposited in GenBank. In contrast to previous results, this study shows that the MSP of D. viviparus is similar to that of other nematodes. Almost no sequence variation, and thus no antigenic diversity, was detected in MSP between worms from different sub-populations or in the other Dictyocaulus species investigated. A functional test of a recombinant variant of the MSP showed that the expressed protein was recognized by antibodies in sera from infected cattle. This has practical implications for the development of species-specific markers, recombinant vaccines, and immunodiagnostics.
-
Phylogeny of Dictyocaulus (lungworms) from eight species of ruminants based on analyses of ribosomal RNA data.
Parasitology, 2003Co-Authors: Johan Höglund, Elisabeth Wilhelmsson, D. A. Morrison, Billy P. Divina, Jens G. MattssonAbstract:SUMMARY In this study, we conducted phylogenetic analyses of nematode parasites within the genus Dictyocaulus (superfamily Trichostrongyloidea). Lungworms from cattle (Bos taurus), domestic sheep (Ovis aries), European fallow deer (Dama dama), moose (Alces alces), musk ox (Ovibos moschatus), red deer (Cervus elaphus), reindeer (Rangifer tarandus) and roe deer (Capreolus capreolus) were obtained and their small subunit ribosomal RNA (SSU) and internal transcribed spacer 2 (ITS2) sequences analysed. In the hosts examined we identified D. capreolus, D. eckerti, D. filaria and D. viviparus. However, in fallow deer we detected a taxon with unique SSU and ITS2 sequences. The phylogenetic position of this taxon based on the SSU sequences shows that it is a separate evolutionary lineage from the other recognized species of Dictyocaulus. Furthermore, the analysis of the ITS2 sequence data indicates that it is as genetically distinct as are the named species of Dictyocaulus. Therefore, either this taxon needs to be recognized as a new species, or D. capreolus, D. eckerti and D. viviparus need to be combined into a single species. Traditionally, the genus Dictyocaulus has been placed as a separate family within the superfamily Trichostrongyloidea. The present molecular phylogenetic analyses support the placement as a separate family, but the current data do not support the placement of the Dictyocaulidae within the Trichostrongyloidea without a reassessment of the placement of the superfamily Strongyloidea. While D. eckerti has been regarded as the one and only lungworm species of cervids, this study showed that 4 host species including 3 members of Cervidae (moose, reindeer, red deer) and 1 Bovidae (musk ox) were infected with this parasite. Host ranges of D. viviparus (cattle), D. filaria (sheep) and D. capreolus (moose and roe deer) were more restricted. No clear pattern of co-evolution between the dictyocaulid taxa and their bovid and cervid hosts could be determined.
-
molecular identification and prevalence of Dictyocaulus spp trichostrongyloidea dictyocaulidae in swedish semi domestic and free living cervids
Journal of Wildlife Diseases, 2002Co-Authors: Torsten Mörner, Elisabeth Wilhelmsson, Jens G. Mattsson, Billy P. Divina, Johan HöglundAbstract:Lungs of 102 roe deer (Capreolus capreolus), 136 moose (Alces alces), 68 fallow deer (Dama dama), and six red deer (Cervus elaphus) were examined during hunting seasons from 16 September 1997 to 1 March 2000. The aim was to determine the species composition and prevalence of Dictyocaulus lungworms in these hosts in Sweden. Worms were identified following polymerase chain reaction (PCR) amplification of the internal transcribed spacer of ribosomal DNA (ITS2), followed by hybridization with four species-specific oligonucleotides. In addition, 50 lungworms from five reindeer (Rangifer tarandus) from Norway were similarly analyzed. A total of 399 worms were recovered and analyzed representing a range of 29–128 worms per host species. All specimens from roe deer were identified as Dictyocaulus capreolus, whereas those from red deer and reindeer were identical with D. eckerti. From moose, 73 (81.1%) of the worms were identified as D. capreolus whereas 17 (18.9%) were D. eckerti. The ITS2 sequence of fallow deer...
-
ITS2 sequences of Dictyocaulus species from cattle, roe deer and moose in Sweden: molecular evidence for a new species.
International journal for parasitology, 1999Co-Authors: Johan Höglund, Elisabeth Wilhelmsson, Dan Christensson, Torsten Mörner, Peter J. Waller, Jens G. MattssonAbstract:Total DNA was isolated from adult lungworms of the genus Dictyocaulus, collected from cattle, moose (Alces alces) and roe deer (Capreolus capreolus) in Sweden. The second ribosomal internal transcribed spacer was amplified with PCR, and DNA sequences were determined from nine individual worms that all came from different hosts in order to avoid analysis of siblings. The sequence data obtained were aligned and compared with similar data derived from German lungworm isolates from cattle and fallow deer (Cervus dama). These analyses clearly showed that specimens of the cattle lungworm, Dictyocaulus viviparus, were almost identical irrespective of their geographical origin. However, when the second internal transcribed spacer sequence of D. viviparus was compared with that of lungworms from moose and roe deer, major differences were noticed. Although lungworms collected from these cervids had identical second internal transcribed spacer sequences, they proved to be genetically different from Dictyocaulus eckerti of German fallow deer, displaying a 66.5% similarity. In an evolutionary tree, inferred by maximum likelihood analysis, the Dictyocaulus species from cattle and wild cervids clustered as compared with Dictyocaulus filaria from sheep. The study has thus demonstrated that A. alces and C. capreolus in Sweden are parasitised with a Dictyocaulus species that is different from D. viviparus and D. eckerti, indicating that we are dealing with a new species in moose and roe deer.
Robin B Gasser - One of the best experts on this subject based on the ideXlab platform.
-
analysis of the transcriptome of adult Dictyocaulus filaria and comparison with Dictyocaulus viviparus with a focus on molecules involved in host parasite interactions
International Journal for Parasitology, 2014Co-Authors: Stefano Mangiola, Jeanpierre Y Scheerlinck, Pasi K Korhonen, Makedonka Mitreva, Neil D Young, Paul W Sternberg, Andreas Hofmann, Christina Strube, Robin B GasserAbstract:Parasitic nematodes cause diseases of major economic importance in animals. Key representatives are species of Dictyocaulus (=lungworms), which cause bronchitis (=dictyocaulosis, commonly known as “husk”) and have a major adverse impact on the health of livestock. In spite of their economic importance, very little is known about the immunomolecular biology of these parasites. Here, we conducted a comprehensive investigation of the adult transcriptome of Dictyocaulus filaria of small ruminants and compared it with that of Dictyocaulus viviparus of bovids. We then identified a subset of highly transcribed molecules inferred to be linked to host–parasite interactions, including cathepsin B peptidases, fatty-acid and/or retinol-binding proteins, β-galactoside-binding galectins, secreted protein 6 precursors, macrophage migration inhibitory factors, glutathione peroxidases, a transthyretin-like protein and a type 2-like cystatin. We then studied homologues of D. filaria type 2-like cystatin encoded in D. viviparus and 24 other nematodes representing seven distinct taxonomic orders, with a particular focus on their proposed role in immunomodulation and/or metabolism. Taken together, the present study provides new insights into nematode–host interactions. The findings lay the foundation for future experimental studies and could have implications for designing new interventions against lungworms and other parasitic nematodes. The future characterisation of the genomes of Dictyocaulus spp. should underpin these endeavours.
-
Assessment of the genetic relationship between Dictyocaulus species from Bos taurus and Cervus elaphus using complete mitochondrial genomic datasets.
Parasites & vectors, 2012Co-Authors: Robin B Gasser, Abdul Jabbar, Namitha Mohandas, Johan Höglund, Ross S. Hall, D. Timothy J. Littlewood, Aaron R. JexAbstract:Background Dictyocaulus species are strongylid nematodes of major veterinary significance in ruminants, such as cattle and cervids, and cause serious bronchitis or pneumonia (dictyocaulosis or “husk”). There has been ongoing controversy surrounding the validity of some Dictyocaulus species and their host specificity. Here, we sequenced and characterized the mitochondrial (mt) genomes of Dictyocaulus viviparus (from Bos taurus) with Dictyocaulus sp. cf. eckerti from red deer (Cervus elaphus), used mt datasets to assess the genetic relationship between these and related parasites, and predicted markers for future population genetic or molecular epidemiological studies.
-
Assessment of the genetic relationship between Dictyocaulus species from Bos taurus and Cervus elaphus using complete mitochondrial genomic datasets
Parasites & Vectors, 2012Co-Authors: Robin B Gasser, Abdul Jabbar, Namitha Mohandas, Johan Höglund, Ross S. Hall, D. Timothy J. Littlewood, Aaron R. JexAbstract:Background Dictyocaulus species are strongylid nematodes of major veterinary significance in ruminants, such as cattle and cervids, and cause serious bronchitis or pneumonia (dictyocaulosis or “husk”). There has been ongoing controversy surrounding the validity of some Dictyocaulus species and their host specificity. Here, we sequenced and characterized the mitochondrial (mt) genomes of Dictyocaulus viviparus (from Bos taurus ) with Dictyocaulus sp. cf. eckerti from red deer ( Cervus elaphus ), used mt datasets to assess the genetic relationship between these and related parasites, and predicted markers for future population genetic or molecular epidemiological studies. Methods The mt genomes were amplified from single adult males of D. viviparus and Dictyocaulus sp. cf. eckerti (from red deer) by long-PCR, sequenced using 454-technology and annotated using bioinformatic tools. Amino acid sequences inferred from individual genes of each of the two mt genomes were compared, concatenated and subjected to phylogenetic analysis using Bayesian inference (BI), also employing data for other strongylids for comparative purposes. Results The circular mt genomes were 13,310 bp ( D. viviparus ) and 13,296 bp ( Dictyocaulus sp. cf. eckerti ) in size, and each contained 12 protein-encoding, 22 transfer RNA and 2 ribosomal RNA genes, consistent with other strongylid nematodes sequenced to date. Sliding window analysis identified genes with high or low levels of nucleotide diversity between the mt genomes. At the predicted mt proteomic level, there was an overall sequence difference of 34.5% between D. viviparus and Dictyocaulus sp. cf. eckerti , and amino acid sequence variation within each species was usually much lower than differences between species. Phylogenetic analysis of the concatenated amino acid sequence data for all 12 mt proteins showed that both D. viviparus and Dictyocaulus sp. cf. eckerti were closely related, and grouped to the exclusion of selected members of the superfamilies Metastrongyloidea, Trichostrongyloidea, Ancylostomatoidea and Strongyloidea. Conclusions Consistent with previous findings for nuclear ribosomal DNA sequence data, the present analyses indicate that Dictyocaulus sp. cf. eckerti (red deer) and D. viviparus are separate species. Barcodes in the two mt genomes and proteomes should serve as markers for future studies of the population genetics and/or epidemiology of these and related species of Dictyocaulus .
-
A transcriptomic analysis of the adult stage of the bovine lungworm, Dictyocaulus viviparus
BMC genomics, 2007Co-Authors: Shoba Ranganathan, Christina Strube, Shivashankar H. Nagaraj, Thomas Schnieder, Robin B GasserAbstract:Background Lungworms of the genus Dictyocaulus (family Dictyocaulidae) are parasitic nematodes of major economic importance. They cause pathological effects and clinical disease in various ruminant hosts, particularly in young animals. Dictyocaulus viviparus, called the bovine lungworm, is a major pathogen of cattle, with severe infections being fatal. In this study, we provide first insights into the transcriptome of the adult stage of D. viviparus through the analysis of expressed sequence tags (ESTs).
J. Höglund - One of the best experts on this subject based on the ideXlab platform.
-
Dictyocaulus capreolus n. sp. (Nematoda: Trichostrongyloidea) from roe deer, Capreolus capreolus and moose, Alces alces in Sweden
Journal of helminthology, 2002Co-Authors: L.m. Gibbons, J. HöglundAbstract:Dictyocaulus capreolus n. sp. recovered from roe deer, Capreolus capreolus and moose, Alces alces in Sweden is described and figured. Morphological studies revealed the new species to be closest to D. eckerti and D. africanus on the basis of mouth shape, all three species having an elongate mouth opening. The other species of the genus, including D. viviparus, all have a circular to oval mouth opening. Dictyocaulus capreolus n. sp. can be distinguished from D. eckerti and D. africanus on the basis of the morphology of the buccal capsule and the bursa. These morphological studies support earlier evidence of the presence of a new species of Dictyocaulus in roe deer and moose that could be distinguished from D. eckerti and D. viviparus using either a PCR-linked hybridization assay or image analysis software to study the dimensions of the buccal capsule.
-
Identification of Dictyocaulus spp. in ruminants by morphological and molecular analyses.
Parasitology, 2000Co-Authors: B P Divina, E Wilhelmsson, J G Mattsson, P Waller, J. HöglundAbstract:Lungworms of the genus Dictyocaulus from cattle, roe deer, and moose in Sweden were subjected to morphological and molecular analyses. The objectives of the study were to investigate whether mixed or monospecific Dictyocaulus infections occur in Swedish cattle and whether wild cervids may act as reservoirs. The morphological characters examined were thickness and shape of the buccal capsule wall (BCW) and total spicular length (TSL). Morphometry was also done on the total body length, and BCW thickness and length. In the molecular identification, we used a PCR-linked hybridization assay to probe worm DNA with species-specific oligonucleotide probes to the second internal transcribed spacer (1TS2). The results showed that the BCW shape was the most reliable morphological character for identification. Significant differences were observed in this character, but an overlap occurred between lungworms from each of the host species. With the hybridization assay, all lungworms from cattle were identified as D. viviparus, whereas those from roe deer represented a novel Dictyocaulus species demonstrating that each host had a monospecific lungworm infection. In moose, 61 (78.2%) worms belonged to the new species and 17 (21.8%) were D. eckerti. This study shows the usefulness of hybridization assay as an epidemiological tool for the specific identification of lungworms of cattle and wild cervids.