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Michael S. Duffy - One of the best experts on this subject based on the ideXlab platform.
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protein glycosylation in Parelaphostrongylus tenuis first description of the galα1 3gal sequence in a nematode
Glycobiology, 2006Co-Authors: Michael S. Duffy, Howard R. Morris, Anne Dell, Judith A. Appleton, Stuart M. HaslamAbstract:The white-tailed deer is the definitive host of the parasitic nematode Parelaphostrongylus tenuis. This parasite also infects a wide variety of domesticated livestock, causing a debilitating neurologic disease. Glycoconjugates are becoming increasingly implicated in nematode strategies to maintain persistent infections in immunologically competent hosts. In this study, we have carried out detailed mass spectrometric analysis together with classical biochemical techniques, including western blotting and immunohistochemical staining with anticarbohydrate monoclonal antibodies and have shown that P. tenuis contains complex-type N-glycans with the antennae capped with Galalpha1-3Galbeta1-4GlcNAc sequence. By mimicking a vertebrate glycan, Galalpha1-3Gal may aid the parasite in evading immunological detection by the host. This is the first report of the Galalpha1-3Gal sequence in a nematode.
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Cathepsin B homologue at the interface between a parasitic nematode and its intermediate host.
Infection and immunity, 2006Co-Authors: Michael S. Duffy, Deanne K. Cevasco, Dante S. Zarlenga, Woraporn Sukhumavasi, Judith A. AppletonAbstract:Parelaphostrongylus tenuis is a parasitic nematode that causes a debilitating neurologic disease in many North American cervids and domestic livestock species. We produced a PCR-based cDNA library from infective larvae (L3) in order to identify molecules that mediate parasitism. A dominant 1,250-bp amplicon encoded a homologue of cathepsin B cysteine proteases. The sequence incorporated a C29G substitution in the putative active site. Antibodies generated against a recombinant form detected the native protein (PtCPR-1) in Western blot assays of L3, but not adult worm, extracts. Immunohistochemical methods revealed that PtCPR-1 synthesis was restricted to larval stages within the snail intermediate host (Triodopsis sp.), beginning as early as 2 days postinfection (dpi) of snails. The protein was present in the intestine and luminal contents and was lost from larvae over time. Concurrent studies showed that larvae induced an immune response in snails beginning at 1 dpi. Layers of hemocytes encapsulated larvae immediately after infection, and granuloma-like structures formed around parasites in chronic infections. Loss of PtCPR-1 from L3 and its accumulation in host tissues coincided with degeneration of granuloma architecture 90 to 105 dpi. Fully developed L3 emerged from the snail at this time. Our data implicate PtCPR-1 in larval development and possibly in the emergence of P. tenuis from the intermediate host. Emerged L3 survived desiccation and cold stress, suggesting that they could remain infectious in the environment. Molecules promoting emergence would facilitate dispersal of L3 and increase the likelihood of transmission to definitive hosts.
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Application of monoclonal antibodies in functional and comparative investigations of heavy-chain immunoglobulins in new world camelids.
Clinical and diagnostic laboratory immunology, 2005Co-Authors: L. P. Daley, Michael S. Duffy, Mary C. Smith, Lucille F. Gagliardo, Judith A. AppletonAbstract:Of the three immunoglobulin G (IgG) isotypes described to occur in camelids, IgG2 and IgG3 are distinct in that they do not incorporate light chains. These heavy-chain antibodies (HCAbs) constitute approximately 50% of the IgG in llama serum and as much as 75% of the IgG in camel serum. We have produced isotype-specific mouse monoclonal antibodies (MAbs) in order to investigate the roles of HCAbs in camelid immunity. Seventeen stable hybridomas were cloned, and three MAbs that were specific for epitopes on the gamma chains of llama IgG1, IgG2, or IgG3 were characterized in detail. Affinity chromatography revealed that each MAb bound its isotype in solution in llama serum. The antibodies bound to the corresponding alpaca IgGs, to guanaco IgG1 and IgG2, and to camel IgG1. Interestingly, anti-IgG2 MAbs bound three heavy-chain species in llama serum, confirming the presence of three IgG2 subisotypes. Two IgG2 subisotypes were detected in alpaca and guanaco sera. The MAbs detected llama serum IgGs when they were bound to antigen in enzyme-linked immunosorbent assays and were used to discern among isotypes induced during infection with a parasitic nematode. Diseased animals, infected with Parelaphostrongylus tenuis, did not produce antigen-specific HCAbs; rather, they produced the conventional isotype, IgG1, exclusively. Our data document the utility of these MAbs in functional and physiologic investigations of the immune systems of New World camelids.
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establishment of adult Parelaphostrongylus tenuis patent infections and acquired immunity after experimental infection of white tailed deer odocoileus virginianus and red deer cervus elaphus elaphus
Journal of Parasitology, 2004Co-Authors: Michael S. Duffy, Trent A Greaves, Michael D. B. BurtAbstract:Experimental Parelaphostrongylus tenuis infections were established in white-tailed deer (Odocoileus virginianus) and an atypical host, red deer (Cervus elaphus elaphus). Groups of deer were fed 10, 25, or 100 third-stage larvae (L3) of P. tenuis and received a single equivalent challenge exposure at varying intervals. Infections were monitored up to 6 yr in white- tailed deer and up to 2.8 yr in red deer. The prepatent period in white-tailed deer varied from 91 to 1,072 days (381 ± 374) and in red deer from 105 to 358 days (167 ± 77). Adult worms lived for up to 6 yr in white-tailed deer. Although most had patent infections until necropsy, latent periods were observed regardless of season. Adult worms lived for up to 2.8 yr in red deer, and patent infections persisted for 20–363 days (152 ± 106). Patent infections were correlated with the presence of adult worms in blood vessels and sinuses of both deer species. Worms were restricted to the subdural space in all deer with latent and occult infections. Ad...
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IDENTIFICATION OF ANTIGENS WITH POTENTIAL FOR IMMUNODIAGNOSIS OF Parelaphostrongylus TENUIS AND ELAPHOSTRONGYLUS CERVI INFECTIONS IN RED DEER (CERVUS ELAPHUS ELAPHUS)
The Journal of parasitology, 2002Co-Authors: Michael S. Duffy, Michael D. B. BurtAbstract:Red deer (Cervus elaphus elaphus) were infected experimentally with Parelaphostrongylus tenuis in New Brunswick, Canada, and with Elaphostrongylus cervi in New Zealand. Excretory–secretory (E–S) antigens from adult P. tenuis were evaluated for their serodiagnostic potential in identifying P. tenuis and heterologous E. cervi infections in a Western blot. The antigen recognition profile of sera from animals infected with P. tenuis varied between individuals and with duration of infections, whereas that of pooled sera from animals infected with E. cervi showed less variation. A single molecule of 42–43 kDa was recognized consistently by sera from all animals infected with either P. tenuis or E. cervi. Sera from unexposed control deer and from those with other heterologous nematode infections did not consistently identify this antigen. Serorecognition of the 42–43-kDa antigen by deer infected with P. tenuis resulted in a sensitivity of 99% and a specificity of 85% (≥1 mo postinfection). Although antibody to t...
Polley L. - One of the best experts on this subject based on the ideXlab platform.
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Protostrongylid Parasites and Pneumonia in Captive and Wild Thinhorn Sheep (\u3ci\u3eOvis dalli\u3c/i\u3e)
DigitalCommons@University of Nebraska - Lincoln, 2007Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz, Susan J., Veitch A. M., Elkin B. T., Bollinger T. K., Chirino-trejo J. M., West K. H., Polley L.Abstract:We describe health significance of protostrongylid parasites (Parelaphostrongylus odocoilei and Protostrongylus stilesi) and other respiratory pathogens in more than 50 naturally infected Dall’s sheep (Ovis dalli dalli) from the Mackenzie Mountains, Northwest Territories (1998–2002) as well as in three Stone’s sheep (O. d. stonei) experimentally infected with P. odocoilei (2000–2002). Histological lesions in the brain and distribution of P. odocoilei in the muscles of experimentally and naturally infected sheep were consistent with a previously hypothesized ‘‘central nervous system to muscle’’ pattern of migration for P. odocoilei. Dimensions of granulomas associated with eggs of P. odocoilei and density of protostrongylid eggs and larvae in the cranial lung correlated with intensity of larvae in feces, and all varied with season of collection. Prevalence of P. stilesi based on the presence of larvae in feces underestimated true prevalence (based on examination of lungs) in wild Dall’s sheep collected in summer and fall. Similarly, counts of both types of protostrongylid larvae in feces were unreliable indicators of parasitic infection in wild Dall’s sheep with concomitant bacterial pneumonia associated with Arcanobacterium pyogenes, Pasteurella sp., and Mannheimia sp. Diffuse, interstitial pneumonia due to P. odocoilei led to fatal pulmonary hemorrhage and edema after exertion in one experimentally infected Stone’s sheep and one naturally infected Dall’s sheep. Bacterial and verminous pneumonia associated with pathogens endemic in wild Dall’s sheep in the Mackenzie Mountains caused sporadic mortalities. There was no evidence of respiratory viruses or bacterial strains associated with domestic ruminants, from which this population of wild sheep has been historically isolated
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Bionomics of Larvae of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Nematoda: Protostrongylidae) in Experimentally Infected Gastropod Intermediate Hosts
DigitalCommons@University of Nebraska - Lincoln, 2006Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz S. J., Polley L.Abstract:Parelaphostrongylus odocoilei is a protostrongylid parasite that has recently been recognized at several locations in sub-Arctic, but not Arctic, North America. We investigated factors that may determine the distribution of P. odocoilei, including suitable gastropod intermediate hosts, temperature requirements for larval development in gastropods, and larval emergence facilitating overwinter transmission. We collected and experimentally infected gastropods from a site in the sub- Arctic where P. odocoilei is at the northern limit of its distribution. Deroceras laeve, Catinella sp., and Euconulus cf. fulvus, but not members of the Pupillidae, were suitable intermediate hosts. We describe bionomics of larvae of P. odocoilei in D. laeve and Catinella sp. Infective larvae emerged from all slugs (D. laeve) and 60% of Catinella sp. snails, and emergence from D. laeve was intensity dependent. Emerged infective larvae survived up to 6 months under conditions approximating that of the subnivean environment. In D. laeve, there was a direct relationship between temperature and development rate of larvae of P. odocoilei. Larvae of P. odocoilei did not develop to infective stage below the theoretical threshold (8.5°C), and required a minimum of 163 degree days to complete development. These developmental parameters can be incorporated into a model to predict larval development in the field. Knowledge of the factors influencing larval bionomics provides the foundation for predicting temporal and spatial patterns of parasite distribution, abundance, and transmission
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Development and Pathogenesis of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Nematoda: Protostrongylidae) in Experimentally Infected Thinhorn Sheep (\u3ci\u3eOvis dalli\u3c/i\u3e)
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Polley L.Abstract:Recently, the protostrongylid nematode Parelaphostrongylus odocoilei has been reported in a new host species, thinhorn sheep (Ovis dalli). For the first time, we completed the life cycle of P. odocoilei in three Stone’s sheep (O. dalli stonei) and two thinhorn hybrids (O. dalli stonei × O. dalli dalli), each infected with 200 third-stage larvae from slugs (Deroceras laeve). The prepatent period ranged from 68 days to 74 days, and shedding of first-stage larvae (L1) peaked at \u3e10,000 L1 per gram of feces between 90 and 110 days postinfection. A total of 75, 27, and 14 adult P. odocoilei were recovered from skeletal muscles of three Stone’s sheep. Starting in the prepatent period, all infected sheep lost weight and developed peripheral eosinophilia. At two weeks before patency, two thinhorn hybrids developed neurologic signs (hind end ataxia, loss of conscious proprioception, and hyperesthesia) that resolved at patency. Eosinophilic pleocytosis and antibody to Parelaphostrongylus spp. were detected in the cerebrospinal fluid of the affected sheep, suggesting that the migration route of the muscleworm P. odocoilei may involve the central nervous system. Twenty days after treatment with ivermectin, neurologic signs recurred and larval shedding ceased in one infected thinhorn hybrid, whereas multiple treatments transiently suppressed but did not eliminate larval shedding in the other. During patency, two Stone’s sheep with numerous eggs and larvae of P. odocoilei in the lungs died of respiratory failure following anesthesia or exertion. Parelaphostrongylus odocoilei has widespread geographic distribution, high prevalence, the possibility of causing neurologic and respiratory disease, resistance to treatment, and may constitute a significant emerging disease risk for thinhorn sheep
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New Host and Geographic Records for Two Protostrongylids in Dall\u27s Sheep
DigitalCommons@University of Nebraska - Lincoln, 2001Co-Authors: Kutz, Susan J., Hoberg, Eric P., Veitch A. M., Elkin B. T., Jenkins, Emily J., Polley L.Abstract:Biodiversity survey and inventory have resulted in new information on the distribution of Protostrongylidae in Dall’s sheep (Ovis dalli dalli) from the Northwest Territories (Northwest Territories, Canada) and from Alaska (Alaska, USA). In 1998, Parelaphostrongylus odocoilei adults were found for the first time in the skeletal muscles of Dall’s sheep in the Mackenzie Mountains (Northwest Territories). Adult P. odocoilei were associated with petechial and ecchymotic hemorrhages and localized myositis; eggs and larvae in the lungs were associated with diffuse granulomatous pneumonia. Experimental infections of the slugs Deroceras laeve and Deroceras reticulatum with dorsal-spined first-stage larvae assumed to be P. odocoilei, from ground-collected feces from Dall’s sheep in the Mackenzie Mountains, yielded third-stage larvae by at least 28 (in D. laeve) and 48 (in D. reticulatum) days post-infection. Third-stage larvae emerged from D. laeve between days 19 and 46 post-infection and emergence occurred both at room temperature and at 10 to 12 °C. Protostrongylus stilesi were definitively identified from the lungs of Dall’s sheep collected in the Mackenzie Mountains, Northwest Territories in 1998. Specimens collected from sheep in the Mackenzie Mountains, Northwest Territories in 1971–72, and the Alaska Range, Alaska in 1972 were also confirmed as P. stilesi. Lung pathology associated with adults, eggs, and larvae of P. stilesi was similar to that described in bighorn sheep (Ovis canadensis). Concurrent infections with P. odocoilei and P. stilesi in a single host have not been previously reported
Hoberg, Eric P. - One of the best experts on this subject based on the ideXlab platform.
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Muscleworms, \u3ci\u3eParelaphostrongylus andersoni\u3c/i\u3e (Nematoda: Protostrongylidae), Discovered in Columbia White-Tailed Deer from Oregon and Washington: Implications for Biogeography and Host Associations
DigitalCommons@University of Nebraska - Lincoln, 2008Co-Authors: Asmundsson, Ingrid M., Mortenson, Jack A., Hoberg, Eric P.Abstract:Parelaphostrongylus andersoni is considered a characteristic nematode infecting white-tailed deer (Odocoileus virginianus). Host and geographic distribution for this parasite, however, remain poorly defined in the region of western North America. Fecal samples collected from Columbia white-tailed deer (O. v. leucurus) in a restricted range endemic to Oregon and Washington, USA, were examined for dorsal-spined larvae characteristic of many protostrongylid nematodes. Multilocus DNA sequence data (internal transcribed spacer 2 and cytochrome c oxidase subunit 1) established the identity and a new record for P. andersoni in a subspecies of white-tailed deer previously unrecognized as hosts. Populations of P. andersoni are now recognized along the basin of the lower Columbia River in Oregon and Washington and from south-central Oregon on the North Umpqua River. Current data indicate a potentially broad zone of sympatry for P. andersoni and Parelaphostrongylus odocoilei in the western region of North America, although these elaphostrongylines seem to be segregated, respectively, in white-tailed deer or in black-tailed and mule deer (Odocoileus hemionus) at temperate latitudes. The geographic range for P. andersoni in white-tailed deer is extended substantially to the west of the currently defined limit in North America, and we confirm an apparently extensive range for this elpahostrongyline. These observations are explored in the broader context of host and geographic associations for P. andersoni and related elaphostrongylines in North American cervids
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Protostrongylid Parasites and Pneumonia in Captive and Wild Thinhorn Sheep (\u3ci\u3eOvis dalli\u3c/i\u3e)
DigitalCommons@University of Nebraska - Lincoln, 2007Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz, Susan J., Veitch A. M., Elkin B. T., Bollinger T. K., Chirino-trejo J. M., West K. H., Polley L.Abstract:We describe health significance of protostrongylid parasites (Parelaphostrongylus odocoilei and Protostrongylus stilesi) and other respiratory pathogens in more than 50 naturally infected Dall’s sheep (Ovis dalli dalli) from the Mackenzie Mountains, Northwest Territories (1998–2002) as well as in three Stone’s sheep (O. d. stonei) experimentally infected with P. odocoilei (2000–2002). Histological lesions in the brain and distribution of P. odocoilei in the muscles of experimentally and naturally infected sheep were consistent with a previously hypothesized ‘‘central nervous system to muscle’’ pattern of migration for P. odocoilei. Dimensions of granulomas associated with eggs of P. odocoilei and density of protostrongylid eggs and larvae in the cranial lung correlated with intensity of larvae in feces, and all varied with season of collection. Prevalence of P. stilesi based on the presence of larvae in feces underestimated true prevalence (based on examination of lungs) in wild Dall’s sheep collected in summer and fall. Similarly, counts of both types of protostrongylid larvae in feces were unreliable indicators of parasitic infection in wild Dall’s sheep with concomitant bacterial pneumonia associated with Arcanobacterium pyogenes, Pasteurella sp., and Mannheimia sp. Diffuse, interstitial pneumonia due to P. odocoilei led to fatal pulmonary hemorrhage and edema after exertion in one experimentally infected Stone’s sheep and one naturally infected Dall’s sheep. Bacterial and verminous pneumonia associated with pathogens endemic in wild Dall’s sheep in the Mackenzie Mountains caused sporadic mortalities. There was no evidence of respiratory viruses or bacterial strains associated with domestic ruminants, from which this population of wild sheep has been historically isolated
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\u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e in Columbia Black-Tailed Deer from Oregon
DigitalCommons@University of Nebraska - Lincoln, 2006Co-Authors: Mortenson, Jack A., Hoberg, Eric P., Rosenthal, Benjamin M., Abrams Arthur, Dunams Detiger, Bildfell, Robert J., Green, Richard L.Abstract:Documenting the occurrence of Parelaphostrongylus odocoilei has historically relied on the morphological examination of adult worms collected from the skeletal muscle of definitive hosts, including deer. Recent advances in the knowledge of protostrongylid genetic sequences now permit larvae to be identified. Dorsal-spined larvae (DSLs) collected in 2003–2004 from the lung and feces of six Columbian black-tailed deer (Odocoileus hemionus columbianus) from Oregon were characterized genetically. The sequences from unknown DSLs were compared to those from morphologically validated adults and larvae of P. odocoilei at both the second internal transcribed spacer (ITS-2) of ribosomal DNA and the mitochondrial cytochrome oxidase II gene. We provide the first unequivocal identification of P. odocoilei in Columbian black-tailed deer from Oregon. The broader geographic distribution, prevalence, and pathology of P. odocoilei are not known in populations of Oregon deer
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Bionomics of Larvae of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Nematoda: Protostrongylidae) in Experimentally Infected Gastropod Intermediate Hosts
DigitalCommons@University of Nebraska - Lincoln, 2006Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz S. J., Polley L.Abstract:Parelaphostrongylus odocoilei is a protostrongylid parasite that has recently been recognized at several locations in sub-Arctic, but not Arctic, North America. We investigated factors that may determine the distribution of P. odocoilei, including suitable gastropod intermediate hosts, temperature requirements for larval development in gastropods, and larval emergence facilitating overwinter transmission. We collected and experimentally infected gastropods from a site in the sub- Arctic where P. odocoilei is at the northern limit of its distribution. Deroceras laeve, Catinella sp., and Euconulus cf. fulvus, but not members of the Pupillidae, were suitable intermediate hosts. We describe bionomics of larvae of P. odocoilei in D. laeve and Catinella sp. Infective larvae emerged from all slugs (D. laeve) and 60% of Catinella sp. snails, and emergence from D. laeve was intensity dependent. Emerged infective larvae survived up to 6 months under conditions approximating that of the subnivean environment. In D. laeve, there was a direct relationship between temperature and development rate of larvae of P. odocoilei. Larvae of P. odocoilei did not develop to infective stage below the theoretical threshold (8.5°C), and required a minimum of 163 degree days to complete development. These developmental parameters can be incorporated into a model to predict larval development in the field. Knowledge of the factors influencing larval bionomics provides the foundation for predicting temporal and spatial patterns of parasite distribution, abundance, and transmission
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Caudal Polymorphism and Cephalic Morphology among First-Stage Larvae of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Protostrongylidae: Elaphostrongylinae) in Dall’s Sheep from the Mackenzie Mountains, Canada
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Hoberg, Eric P., Kutz, Susan J., Jenkins, Emily J., Rosenthal Benjamin, Wong Mayee, Erbe, Eric F., Polley LyddenAbstract:We demonstrate polymorphism in the structure of the tail among first-stage larvae of Parelaphostrongylus odocoilei (Protostrongylidae). Two distinct larvae, both with a characteristic dorsal spine, include (1) a morphotype with a kinked conical tail marked by three distinct transverse folds or joints and a symmetrical terminal tail spike and (2) a morphotype with a digitate terminal region lacking folds or joints and with an asymmetrical, subterminal tail spike. These divergent larval forms had been postulated as perhaps representing distinct species of elaphostrongyline nematodes. Application of a multilocus approach using ITS-2 sequences from the nuclear genome and COX-II sequences from the mitochondrial genome confirmed the identity of these larvae as P. odocoilei. Additionally, based on scanning electron microscopy (low-temperature field emission), the cephalic region of these larvae consisted of a cuticular triradiate stoma surrounded by six single circumoral papillae of the inner circle, ten papillae of the outer circle (four paired and two single), and two lateral amphids. Ours is the first demonstration of structural polymorphism among larval conspecifics in the Metastrongyloidea and Strongylida. The basis for this polymorphism remains undetermined, but such phenomena, if discovered to be more widespread, may contribute to continued confusion in discriminating among first-stage larvae for species, genera, and subfamilies within Protostrongylidae
Jenkins, Emily J. - One of the best experts on this subject based on the ideXlab platform.
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Protostrongylid Parasites and Pneumonia in Captive and Wild Thinhorn Sheep (\u3ci\u3eOvis dalli\u3c/i\u3e)
DigitalCommons@University of Nebraska - Lincoln, 2007Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz, Susan J., Veitch A. M., Elkin B. T., Bollinger T. K., Chirino-trejo J. M., West K. H., Polley L.Abstract:We describe health significance of protostrongylid parasites (Parelaphostrongylus odocoilei and Protostrongylus stilesi) and other respiratory pathogens in more than 50 naturally infected Dall’s sheep (Ovis dalli dalli) from the Mackenzie Mountains, Northwest Territories (1998–2002) as well as in three Stone’s sheep (O. d. stonei) experimentally infected with P. odocoilei (2000–2002). Histological lesions in the brain and distribution of P. odocoilei in the muscles of experimentally and naturally infected sheep were consistent with a previously hypothesized ‘‘central nervous system to muscle’’ pattern of migration for P. odocoilei. Dimensions of granulomas associated with eggs of P. odocoilei and density of protostrongylid eggs and larvae in the cranial lung correlated with intensity of larvae in feces, and all varied with season of collection. Prevalence of P. stilesi based on the presence of larvae in feces underestimated true prevalence (based on examination of lungs) in wild Dall’s sheep collected in summer and fall. Similarly, counts of both types of protostrongylid larvae in feces were unreliable indicators of parasitic infection in wild Dall’s sheep with concomitant bacterial pneumonia associated with Arcanobacterium pyogenes, Pasteurella sp., and Mannheimia sp. Diffuse, interstitial pneumonia due to P. odocoilei led to fatal pulmonary hemorrhage and edema after exertion in one experimentally infected Stone’s sheep and one naturally infected Dall’s sheep. Bacterial and verminous pneumonia associated with pathogens endemic in wild Dall’s sheep in the Mackenzie Mountains caused sporadic mortalities. There was no evidence of respiratory viruses or bacterial strains associated with domestic ruminants, from which this population of wild sheep has been historically isolated
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Bionomics of Larvae of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Nematoda: Protostrongylidae) in Experimentally Infected Gastropod Intermediate Hosts
DigitalCommons@University of Nebraska - Lincoln, 2006Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz S. J., Polley L.Abstract:Parelaphostrongylus odocoilei is a protostrongylid parasite that has recently been recognized at several locations in sub-Arctic, but not Arctic, North America. We investigated factors that may determine the distribution of P. odocoilei, including suitable gastropod intermediate hosts, temperature requirements for larval development in gastropods, and larval emergence facilitating overwinter transmission. We collected and experimentally infected gastropods from a site in the sub- Arctic where P. odocoilei is at the northern limit of its distribution. Deroceras laeve, Catinella sp., and Euconulus cf. fulvus, but not members of the Pupillidae, were suitable intermediate hosts. We describe bionomics of larvae of P. odocoilei in D. laeve and Catinella sp. Infective larvae emerged from all slugs (D. laeve) and 60% of Catinella sp. snails, and emergence from D. laeve was intensity dependent. Emerged infective larvae survived up to 6 months under conditions approximating that of the subnivean environment. In D. laeve, there was a direct relationship between temperature and development rate of larvae of P. odocoilei. Larvae of P. odocoilei did not develop to infective stage below the theoretical threshold (8.5°C), and required a minimum of 163 degree days to complete development. These developmental parameters can be incorporated into a model to predict larval development in the field. Knowledge of the factors influencing larval bionomics provides the foundation for predicting temporal and spatial patterns of parasite distribution, abundance, and transmission
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Caudal Polymorphism and Cephalic Morphology among First-Stage Larvae of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Protostrongylidae: Elaphostrongylinae) in Dall’s Sheep from the Mackenzie Mountains, Canada
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Hoberg, Eric P., Kutz, Susan J., Jenkins, Emily J., Rosenthal Benjamin, Wong Mayee, Erbe, Eric F., Polley LyddenAbstract:We demonstrate polymorphism in the structure of the tail among first-stage larvae of Parelaphostrongylus odocoilei (Protostrongylidae). Two distinct larvae, both with a characteristic dorsal spine, include (1) a morphotype with a kinked conical tail marked by three distinct transverse folds or joints and a symmetrical terminal tail spike and (2) a morphotype with a digitate terminal region lacking folds or joints and with an asymmetrical, subterminal tail spike. These divergent larval forms had been postulated as perhaps representing distinct species of elaphostrongyline nematodes. Application of a multilocus approach using ITS-2 sequences from the nuclear genome and COX-II sequences from the mitochondrial genome confirmed the identity of these larvae as P. odocoilei. Additionally, based on scanning electron microscopy (low-temperature field emission), the cephalic region of these larvae consisted of a cuticular triradiate stoma surrounded by six single circumoral papillae of the inner circle, ten papillae of the outer circle (four paired and two single), and two lateral amphids. Ours is the first demonstration of structural polymorphism among larval conspecifics in the Metastrongyloidea and Strongylida. The basis for this polymorphism remains undetermined, but such phenomena, if discovered to be more widespread, may contribute to continued confusion in discriminating among first-stage larvae for species, genera, and subfamilies within Protostrongylidae
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Geographic Distribution of the Muscle-Dwelling Nematode \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e in North America, Using Molecular Identification of First-Stage Larvae
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Kutz, Susan J., Appleyard, Greg D., Rosenthal, Benjamin M., Veitch, Alasdair M., Schwantje, Helen M., Elkin, Brett T., Polley LyddenAbstract:Molecular identification of dorsal-spined larvae (DSL) from fecal samples indicates that the protostrongylid parasite Parelaphostrongylus odocoilei occupies a broader geographic range in western North America than has been previously reported. We analyzed 2,124 fecal samples at 29 locations from thinhorn sheep (Ovis dalli dalli and O. d. stonei), bighorn sheep (Ovis canadensis canadensis and O. c. californiana), mountain goats (Oreamnos americanus), woodland caribou (Rangifer tarandus caribou), mule deer (Odocoileus hemionus hemionus), and black-tailed deer (O. h. columbianus). The DSL were recovered from populations of thinhorn sheep south, but not north, of the Arctic Circle, and they were not recovered from any of the bighorn sheep populations that we examined. In total, DSL were recovered from 20 locations in the United States and Canada (Alaska, Yukon Territory, Northwest Territories, British Columbia, Alberta, and California). The DSL were identified as P. odocoilei by comparing sequences of the second internal transcribed spacer (ITS2) region of ribosomal RNA among 9 protostrongylid species validated by adult comparative morphology. The ITS2 sequences were markedly different between Parelaphostrongylus and other protostrongylid genera. Smaller fixed differences served as diagnostic markers for the three species of Parelaphostrongylus. The ITS2 sequences (n = 60) of P. odocoilei were strongly conserved across its broad geographic range from California to Alaska. Polymorphism at 5 nucleotide positions was consistent with multiple copies of the ITS2 within individual specimens of P. odocoilei. This work combines extensive fecal surveys, comparative morphology, and molecular diagnostic techniques to describe comprehensively the host associations and geographic distribution of a parasitic helminth
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Development and Pathogenesis of \u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e (Nematoda: Protostrongylidae) in Experimentally Infected Thinhorn Sheep (\u3ci\u3eOvis dalli\u3c/i\u3e)
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Jenkins, Emily J., Hoberg, Eric P., Polley L.Abstract:Recently, the protostrongylid nematode Parelaphostrongylus odocoilei has been reported in a new host species, thinhorn sheep (Ovis dalli). For the first time, we completed the life cycle of P. odocoilei in three Stone’s sheep (O. dalli stonei) and two thinhorn hybrids (O. dalli stonei × O. dalli dalli), each infected with 200 third-stage larvae from slugs (Deroceras laeve). The prepatent period ranged from 68 days to 74 days, and shedding of first-stage larvae (L1) peaked at \u3e10,000 L1 per gram of feces between 90 and 110 days postinfection. A total of 75, 27, and 14 adult P. odocoilei were recovered from skeletal muscles of three Stone’s sheep. Starting in the prepatent period, all infected sheep lost weight and developed peripheral eosinophilia. At two weeks before patency, two thinhorn hybrids developed neurologic signs (hind end ataxia, loss of conscious proprioception, and hyperesthesia) that resolved at patency. Eosinophilic pleocytosis and antibody to Parelaphostrongylus spp. were detected in the cerebrospinal fluid of the affected sheep, suggesting that the migration route of the muscleworm P. odocoilei may involve the central nervous system. Twenty days after treatment with ivermectin, neurologic signs recurred and larval shedding ceased in one infected thinhorn hybrid, whereas multiple treatments transiently suppressed but did not eliminate larval shedding in the other. During patency, two Stone’s sheep with numerous eggs and larvae of P. odocoilei in the lungs died of respiratory failure following anesthesia or exertion. Parelaphostrongylus odocoilei has widespread geographic distribution, high prevalence, the possibility of causing neurologic and respiratory disease, resistance to treatment, and may constitute a significant emerging disease risk for thinhorn sheep
Eric P. Hoberg - One of the best experts on this subject based on the ideXlab platform.
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the biogeography of the caribou lungworm varestrongylus eleguneniensis nematoda protostrongylidae across northern north america
International journal for parasitology. Parasites and wildlife, 2020Co-Authors: Eric P. Hoberg, Guilherme G Verocai, Manon Simard, Kimberlee B Beckmen, Marco Musiani, Samuel K Wasser, Christine Cuyler, Micheline Manseau, Umer ChaudhryAbstract:Varestrongylus eleguneniensis (Nematoda; Protostrongylidae) is a recently described species of lungworm that infects caribou (Rangifer tarandus), muskoxen (Ovibos moschatus) and moose (Alces americanus) across northern North America. Herein we explore the geographic distribution of V. eleguneniensis through geographically extensive sampling and discuss the biogeography of this multi-host parasite. We analyzed fecal samples of three caribou subspecies (n = 1485), two muskox subspecies (n = 159), and two moose subspecies (n = 264) from across northern North America. Protostrongylid dorsal-spined larvae (DSL) were found in 23.8%, 73.6%, and 4.2% of these ungulates, respectively. A portion of recovered DSL were identified by genetic analyses of the ITS-2 region of the nuclear rDNA or the cytochrome oxidase c subunit I (COI) region of the mtDNA. We found V. eleguneniensis widely distributed among caribou and muskox populations across most of their geographic prange in North America but it was rare in moose. Parelaphostrongylus andersoni was present in caribou and moose and we provide new geographic records for this species. This study provides a substantial expansion of the knowledge defining the current distribution and biogeography of protostrongylid nematodes in northern ungulates. Insights about the host and geographic range of V. eleguneniensis can serve as a geographically extensive baseline for monitoring current distribution and in anticipating future biogeographic scenarios under a regime of accelerating climate and anthropogenic perturbation.
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Surgical extraction of an intraocular infection of Parelaphostrongylus tenuis in a horse
Journal of the American Veterinary Medical Association, 2010Co-Authors: Shelby L. Reinstein, Araceli Lucio-forster, Dwight D. Bowman, Mark L. Eberhard, Eric P. Hoberg, Simon A. Pot, Paul E. MillerAbstract:Case Description—A 4-year-old Hanoverian gelding was evaluated because of a mobile worm-like structure in the right eye. Clinical Findings—Ophthalmologic examination of the right eye revealed a white, thin, coiled, mobile parasite, which was presumed to be a nematode, located in the ventral portion of the anterior chamber of the eye; there also were vitreal strands located temporally and inferiorly near the margin of the pupil. Results of ophthalmologic examination of the left eye were unremarkable. Treatment and Outcome—The horse was treated with a neomycin-polymyxin B-dexamethasone ophthalmic solution applied topically (1 drop, q 8 h) to the right eye and penicillin V potassium (22,000 U/kg [10,000 U/lb], IV, q 6 h). The horse was anesthetized. A stab incision was made in the cornea, and a viscoelastic agent was infused around the parasite. The parasite was extracted via the incision by use of an iris hook and tying forceps. The horse had an uncomplicated recovery from the procedure and retained vision ...
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Serendipitous discovery of a novel protostrongylid (Nematoda: Metastrongyloidea) in caribou, muskoxen, and moose from high latitudes of North America based on DNA sequence comparisons
Canadian Journal of Zoology, 2007Co-Authors: Susan J Kutz, Eric P. Hoberg, Emily J Jenkins, Greg D Appleyard, Ingrid Asmundssoni. Asmundsson, Kimberlee Beckmenk. Beckmen, Marsha Branigan, Lem Butlerl. Butler, Neil B. Chilton, Dorothy CooleyAbstract:Fecal samples are often the only feasible means to assess diversity of parasites in wildlife; however, definitive identification of egg or larval stages in feces by morphology is rarely possible. We determined partial sequences from the second internal transcribed spacer region (ITS-2) of nuclear ribosomal DNA for first-stage, dorsal-spined larvae (DSL) in feces from caribou (Rangifer tarandus tarandus(L., 1758), Rangifer tarandus caribou(Gmelin, 1788), Rangifer tarandus grantii (Allen, 1902)), muskoxen (Ovibos moschatus moschatus(Zimmermann, 1780), Ovibos moschatus wardiLydekker, 1900), moose (Alces alces gigas Miller, 1899 and Alces alces andersoni Peterson, 1952), and from the tissue of one slug (Deroceras laeve (Muller, 1774)) in Arctic-Subarctic North America. A previously uncharacterized, genetically distinct species was recognized based on sequences of 37 DSL from 19 ungulate hosts and the slug. Sequence similarity among in- dividuals of this novel species was 91%-100%. For many individual DSL, paralogues of ITS-2 were detected. ITS-2 se- quences from the novel species were 72%-77% similar to those of Varestrongylus alpenae(Dikmans, 1935) and 51%- 61% similar to those of other protostrongylids known in North American and some Eurasian ungulates. Results indicate a discrete lineage of an undescribed protostrongylid infecting muskoxen, caribou, and moose from Alaska to Labrador. Sym- patric infections with Parelaphostrongylus andersoniPrestwood, 1972 were found in three caribou herds.
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geographic distribution of the muscle dwelling nematode Parelaphostrongylus odocoilei in north america using molecular identification of first stage larvae
Journal of Parasitology, 2005Co-Authors: Emily J Jenkins, Eric P. Hoberg, Greg D Appleyard, Benjamin M Rosenthal, Susan J Kutz, Alasdair Veitch, Helen M Schwantje, Brett Elkin, Lydden PolleyAbstract:Molecular identification of dorsal-spined larvae (DSL) from fecal samples indicates that the protostrongylid parasite Parelaphostrongylus odocoilei occupies a broader geographic range in western North America than has been previously reported. We analyzed 2,124 fecal samples at 29 locations from thinhorn sheep (Ovis dalli dalli and O. d. stonei), bighorn sheep (Ovis canadensis canadensis and O. c. californiana), mountain goats (Oreamnos americanus), woodland caribou (Rangifer tarandus caribou), mule deer (Odocoileus hemionus hemionus), and black-tailed deer (O. h. columbianus). The DSL were recovered from populations of thinhorn sheep south, but not north, of the Arctic Circle, and they were not recovered from any of the bighorn sheep populations that we examined. In total, DSL were recovered from 20 locations in the United States and Canada (Alaska, Yukon Territory, Northwest Territories, British Columbia, Alberta, and California). The DSL were identified as P. odocoilei by comparing sequences of the second internal transcribed spacer (ITS2) region of ribosomal RNA among 9 protostrongylid species validated by adult comparative morphology. The ITS2 sequences were markedly different between Parelaphostrongylus and other protostrongylid genera. Smaller fixed differences served as diagnostic markers for the 3 species of Parelaphostrongylus. The ITS2 sequences (n = 60) of P. odocoilei were strongly conserved across its broad geographic range from California to Alaska. Polymorphism at 5 nucleotide positions was consistent with multiple copies of the ITS2 within individual specimens of P. odocoilei. This work combines extensive fecal surveys, comparative morphology, and molecular diagnostic techniques to describe comprehensively the host associations and geographic distribution of a parasitic helminth.
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Parelaphostrongylus tenuis nematoda protostrongylidae and other parasites of white tailed deer odocoileus virginianus in costa rica
Comparative Parasitology, 2001Co-Authors: Ramon A Carreno, Lance A Durden, Daniel R Brooks, Arthur Abrams, Eric P. HobergAbstract:Parasites were collected from 2 female white-tailed deer (Odocoileus virginianus) in the Area de Conservaci6n Guanacaste, Costa Rica, in early June 1999. Both deer were parasitized by the ticks Amblyomma parvum and Haemaphysalis juxtakochi as well as the hippoboscid fly, Lipoptena mazamae. One deer also hosted the ticks Boophilus microplus, Ixodes affinis, and Anocentor nitens. Both deer were infected by larvae of the nasopharyngeal botfly Cephenemyia jellisoni, and the helminths Eucyathostomum webbi, Gongylonema pulchrum, Parelaphostrongylus tenuis, and Paramphistomum liorchis, whereas Setaria yehi, an undescribed species of Ashworthius, and Onchocerca cervipedis occurred in single hosts. A cysticercus of Taenia omissa was found encapsulated in the lung parenchyma of 1 host. This is the first report of these endoparasites from Central America.
