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J P Dubey - One of the best experts on this subject based on the ideXlab platform.
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confirmation of sarcocystis jamaicensis Sarcocysts in ifn γ gene knockout mice orally inoculated with sporocysts from a red tailed hawk buteo jamaicensis
Journal of Parasitology, 2019Co-Authors: J P Dubey, Joseph Mowery, Rosypal A Von Dohlen, D Scott, Camila K Cerqueiracezar, F H A Murata, David S LindsayAbstract:Here, we report confirmation of Sarcocysts of Sarcocystis jamaicensis in an experimental intermediate host, IFN-γ gene knockout (KO) mice orally inoculated sporocysts from its natural definitive host, a red-tailed hawk ( Buteo jamaicensis) (RTH). A RTH submitted to the Carolina Raptor Center, Huntersville, North Carolina, was euthanized because it could not be rehabilitated and released. Fully sporulated sporocysts from intestinal scrapings of the RTH were orally fed to 2 laboratory-reared outbred Swiss Webster mice (SW; Mus musculus) and to 2 KO mice. The sporocysts were infective for KO mice but not to SW mice. Both SW mice remained asymptomatic, and neither schizonts nor Sarcocysts were found in their tissues when euthanized on day 54 post-inoculation (PI). The KO mice developed neurological signs and were necropsied 38-54 days PI. Schizonts/merozoites were found in both KO mice euthanized and they were confined to the brain. The predominant lesion was meningoencephalitis. Microscopic Sarcocysts were found in muscles of both KO mice. When viewed with light microscopy, the sarcocyst wall appeared thin (<1 μm thick) and smooth. Ultrastructural details of Sarcocysts are described.
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prevalence of Sarcocysts in the muscles of raptors from a rehabilitation center in north carolina
Journal of Parasitology, 2019Co-Authors: Alexa Rosypal Von Dohlen, D Scott, J P DubeyAbstract:The life cycle of Sarcocystis species is heteroxenous (2-host), with carnivores being the definitive host and herbivores serving as intermediate hosts in predator-prey relationships. Raptors (eagles, hawks, falcons, and owls) are apex predators and are not consumed routinely by other carnivores, making the occurrence of Sarcocysts in their muscles unusual. Recent reports of Sarcocysts in eagles and owls with Sarcocystis encephalitis suggests that this condition may be becoming more frequent, and Sarcocystis falcatula has been implicated as the agent of encephalitis in golden ( Aquila chrysaetos) and bald eagles ( Haliaeetus leucocephalus) as well as great horned owls ( Bubo virginianus). The present study was done to determine the prevalence of Sarcocysts of Sarcocystis species in the muscles of raptors from the southeastern United States. Pectoral and heart muscle from 204 raptor patients from the Carolina Raptor Center, Huntersville, North Carolina were tested for the presence of Sarcocystis species using histology. Only a few Sarcocysts were seen in sections of pectoral muscle from 39 of 204 raptors (19.1%) and heart muscle from 9 that also had Sarcocysts in their pectoral muscle. Two structural types of Sarcocysts, thin-walled (1 μm; 62%) or thick-walled (>2 μm, 38%), were seen. Statistical analysis of raptor age and gender was done by Fisher's exact test on samples from raptors with 20 or more samples per group. The prevalence of Sarcocysts by age (2 yr or more) was significant for red-shouldered hawks ( Buteo lineatus) ( P = 0.022) and Cooper's hawks ( Accipiter cooperii) ( P = 0.028). Sarcocyst prevalence in male raptors from these groups evaluated statistically were always less than in females. Prevalence in female red-tailed hawks ( Buteo jamaicensis) (42.1%) was significantly greater than in males (6.7%) using Fisher's exact test ( P = 0.047). Examination of case histories from the 39 sarcocyst-positive raptors did not reveal an association with Sarcocysts in raptor pectoral or heart muscle and in a diagnosis of encephalitis. Additional studies are needed to determine the epidemiology and relationships of Sarcocystis spp. that use raptors as intermediate hosts and the importance of Sarcocystis spp. in the overall wellbeing of raptors in their natural environments.
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sarcocystis strixi n sp from a barred owl strix varia definitive host and interferon gamma gene knockout mice as experimental intermediate host
Journal of Parasitology, 2017Co-Authors: Shiv K. Verma, Joseph Mowery, Benjamin M Rosenthal, J P Dubey, Rosypal A Von Dohlen, D Scott, Camila K Cerqueiracezar, David S LindsayAbstract:Abstract Here we report a new species of Sarcocystis with a barred owl (Strix varia) as the natural definitive host and interferon gamma gene knockout (KO) mice as an experimental intermediate host. A barred owl submitted to the Carolina Raptor Center, Huntersville, North Carolina, was euthanized because of paralysis. Fully sporulated 12.5 × 9.9 μm sporocysts were found in intestinal scrapings from the owl. Sporocysts from the barred owl were orally fed to 4 laboratory-reared outbred Swiss Webster (SW) (Mus musculus) and 8 KO mice. All mice remained asymptomatic. Microscopic Sarcocysts were found in all 5 KO mice euthanized on day 32, 59, 120, 154, and 206 post-inoculation (PI), not in KO mice euthanized on day 4, 8, and 14 PI. Sarcocysts were not found in any SW mice euthanized on day 72, 120, 206, and 210 PI. Sarcocysts were microscopic, up to 70 μm wide. By light microscopy, the sarcocyst wall < 2 μm thick had undulating, flat to conical, protrusions of varying dimensions. Numerous Sarcocysts were seen...
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identification of macroscopic Sarcocysts of sarcocystis cameli from one humped camel camelus dromedarius in iraq
Journal of Parasitology, 2017Co-Authors: J P Dubey, Joseph Mowery, N N Aaji, Rafael CalerobernalAbstract:Abstract There is considerable confusion concerning the identity of macroscopic Sarcocystis species in camels. Currently 2 species, Sarcocystis cameli and Sarcocystis ippeni, are recognized from 1-humped camel (Camelus dromedarius), and Sarcocysts of both species are microscopic. Here, we report the identity of macroscopic Sarcocysts from the C. dromedarius in Iraq as S. cameli. Five Sarcocysts from the muscle of 2 adult camels collected in 1999 and stored in 10% formalin were studied by transmission electron microscopy (TEM). Sarcocysts were 1.5–5.0 mm long and 200–400 μm wide. By TEM, all 5 Sarcocysts had thin sarcocyst walls. Ultrastructurally, the sarcocyst wall had “type 9j” villar protrusions similar to those of S. cameli. This is the first confirmation of macroscopic Sarcocysts from 1-humped camel as S. cameli.
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sarcocystis arctica apicomplexa sarcocystidae ultrastructural description and its new host record the alaskan wolf canis lupus
Parasitology Research, 2016Co-Authors: Rafael Calerobernal, Joseph Mowery, Camila K Cerqueiracezar, Shiv Kumar Verma, Kimberlee B. Beckmen, David Carmena, J P DubeyAbstract:Sarcocystis Sarcocysts are common in muscles of herbivores but are rare in muscles of carnivores. Here, we report Sarcocysts in the muscles of a gray wolf (Canis lupus) from Alaska, USA, for the first time. Sarcocysts extracted from the tongue of the wolf were up to 900 μm long and slender and appeared to have a relatively thin wall by light microscope. By transmission electron microscopy, the sarcocyst wall most closely resembled "type 9c," and had a wavy parasitophorous vacuolar membrane folded as pleomorphic villar protrusions (vp), with anastomoses of tips. The vp and the ground substance (gs) layer were smooth without tubules or granules. The gs was up to 2.0 μm thick. The total width of the wall including vp and the gs was 3.5 μm. The vp were up to 1.5 μm long. Mature Sarcocysts contained numerous bradyzoites and few metrocytes. The bradyzoites were 9.5 μm long and 1.5 μm wide, and contained all organelles found in Sarcocystis bradyzoites with at least two rhoptries. Molecular characterization showed the highest identity for 18S rRNA, 28S rRNA, ITS-1, and cox1 sequences of Sarcocystis arctica of the Arctic fox (Vulpes lagopus) from Norway. The ultrastructure of S. arctica from the fox is unknown. Here, we provide ultrastructure of S. arctica from the Alaskan wolf for the first time. The definitive host of S. arctica remains unknown.
Bjørn Gjerde - One of the best experts on this subject based on the ideXlab platform.
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Morphological and molecular characteristics of six Sarcocystis spp. from red deer (Cervus elaphus) in Spain, including Sarcocystis cervicanis and three new species
Parasitology Research, 2017Co-Authors: Bjørn Gjerde, José María Alunda, Mónica Luzón, Concepción FuenteAbstract:Samples of muscle tissue from the diaphragm, oesophagus and/or heart of eight adult red deer ( Cervus elaphus hispanicus ) from the Quintos de Mora Park in Toledo, Central Spain, were screened for Sarcocysts by means of the compression method. From positive samples, individual Sarcocysts were excised and examined in wet mounts under a light microscope (LM) in order to study their basic morphology before being preserved for molecular studies. In all red deer examined, only microscopic Sarcocysts were found. Those in the diaphragm and oesophagus were spindle-shaped and about 1 × 0.1 mm in size, while those in cardiac muscle were sac-like and 500–800 × 80–180 μm. By LM, the Sarcocysts either had densely packed, about 8-μm-long, hair-like protrusions (type 1), sparsely distributed indistinct projections (fuzzy outline; type 2) or no visible protrusions (smooth surface; type 3). In cardiac muscle, only Sarcocysts without visible protrusions were found. One of the latter Sarcocysts was examined by scanning electron microscopy (SEM) and found to possess thin ribbon-like protrusions. Forty-eight Sarcocysts isolated from the diaphragm, oesophagus and heart of one red deer, as well as 55 Sarcocysts from the heart of three other red deer, 103 Sarcocysts in total, were characterized molecularly through PCR amplification and sequencing of the partial cytochrome c oxidase subunit I gene ( cox1 ) of the mitochondrial genome, revealing the presence of six major cox1 sequence types. Each type comprised either a single sequence (three types) or a collection of several identical or nearly identical sequences. From selected isolates possessing each of these cox1 sequence types, the complete 18S ribosomal RNA (rRNA) gene was amplified and sequenced directly and/or after cloning of the 5′ end half. Supported by the sequence data from the latter gene, as well as the morphology of the Sarcocysts from which the sequences originated, the six cox1 sequence types were considered to represent six separate Sarcocystis spp. Two cox1 sequence types were identified as belonging to the previously characterized species Sarcocystis hjorti (one sequence/sarcocyst) and Sarcocystis linearis (38 sequences/Sarcocysts), respectively, whereas four sequence types were new. One of the latter types was assigned to the previously named species Sarcocystis cervicanis from red deer, since this sequence type was obtained from 52 Sarcocysts from cardiac muscle, which matched the original morphological description (smooth surface) and habitat of this species. The remaining three sequence types were assigned to the three new species Sarcocystis iberica (one sequence/sarcocyst) Sarcocystis venatoria (10 sequences/Sarcocysts) and Sarcocystis morae (one sequence/sarcocyst), respectively. The two species S. iberica and S. venatoria shared the same sarcocyst morphology (type 1) and habitat (diaphragm) and had virtually identical 18S rRNA gene sequences, but differed by 4% at cox1 , which was considered sufficient to regard them as separate species. The single sarcocyst of S. morae (from the oesophagus) examined by LM had a smooth wall and this species was therefore believed to have the same type of ribbon-like protrusions (ultrastructurally) as Sarcocysts of S. cervicanis and S. linearis , which were also the species most closely related to S. morae at cox1 . Thus, there seems to be three species with similar ribbon-like cyst wall protrusions in red deer ( S. cervicanis , S. linearis , S. morae ), as well as three species with similar hair-like protrusions ( S. hjorti , S. iberica , S. venatoria ). Sarcocysts of S. cervicanis were only identified in cardiac muscle, whereas Sarcocysts of S. linearis were found mainly in the diaphragm and oesophagus and rarely in the heart. The relative number of cox1 haplotypes was greater among sequences/isolates of S. linearis (17/38) than among isolates of S. cervicanis (7/52). Four of the species examined ( S. cervicanis , S. linearis , S. iberica , S. venatoria ) possessed considerable intra-isolate (intra-genomic) sequence variation (insertions/deletions, substitutions) in the 18S rRNA gene.
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morphological and molecular characterization of four sarcocystis spp including sarcocystis linearis n sp from roe deer capreolus capreolus in italy
Parasitology Research, 2017Co-Authors: Bjørn Gjerde, Stefano Giacomelli, Alessandro Bianchi, I Bertoletti, Hajime Mondani, Lucia Rita GibelliAbstract:Fresh (frozen/thawed) muscle samples from four 2-12-year-old roe deer (Capreolus capreolus) from the Sondrio province in north-eastern Italy were examined under a dissecting microscope, and about 180 Sarcocysts were isolated and identified to morphological type in wet mounts by light microscopy (LM). Seventy-seven of these Sarcocysts were subsequently examined by molecular methods, comprising polymerase chain reaction (PCR) amplification and sequencing of the partial cytochrome c oxidase subunit I gene (cox1) of all isolates, as well as PCR amplification, cloning and sequencing of the complete18S ribosomal RNA (rRNA) gene of two isolates of each species found. By LM, three major sarcocyst types were recognised: spindle-shaped Sarcocysts, 0.5-3 mm long, either with no clearly recognisable protrusions (thin-walled) or with finger-like protrusions (thick-walled); and slender, thread-like Sarcocysts, 2-3 mm long, with hair-like protrusions. Sequencing of cox1 revealed that the Sarcocysts belonged to four different species. Those with no visible protrusions either belonged to Sarcocystis gracilis (n = 24) or to a Sarcocystis taeniata-like species (n = 19), whereas those with finger- and hair-like protrusions belonged to Sarcocystis silva (n = 27) and Sarcocystis capreolicanis (n = 7), respectively. The 19 cox1 sequences of the S. taeniata-like species, comprising five haplotypes, differed from each other at 0-16 of 1038 nucleotide positions (98.5-100% identity). They differed from 25 previous cox1 sequences of S. taeniata from moose and sika deer (with 98.0-100% intraspecific identity), at 33-43 nucleotide positions (95.9-96.8% interspecific identity), and there were 20 fixed nucleotide differences between the two populations. In the phylogenetic analysis based on cox1 sequences, the two populations formed two separate monophyletic clusters. The S. taeniata-like species in roe deer was therefore considered to represent a separate species, which was named Sarcocystis linearis n. sp. At the 18S rRNA gene, however, the two species could not be clearly separated from each other. Thus, there was considerable intraspecific sequence variation in the 18S rRNA gene of S. linearis (98.1-99.9% identity between 24 sequences), which was similar both in magnitude and nature to the variation previously found in this gene of S. taeniata. The new 18S rRNA gene sequences of S. linearis shared an identity of 97.9-99.6% with those of S. taeniata (overlap between intra- and interspecific identity), and in the phylogenetic tree, sequences of the two species were interspersed. By scanning electron microscopy (SEM), the Sarcocysts of S. linearis were found to possess regularly spaced, thin and narrow ribbon-like cyst wall protrusions (about 2.8-3.2 μm long, 0.3-0.4 μm wide and about 0.02-0.03 μm thick), terminating in a plate-like structure of the same thickness but with an elliptic outline (about 0.3-0.4 μm wide and 0.7-0.9 μm long). The terminal plates were connected in the middle with the band-like portion of the protrusions like the board of a seesaw (tilting board). The terminal plates of adjacent protrusions were neatly arranged in a hexagonal pattern resembling tiles on a roof. Together, they formed an outer roof-like layer facing the surrounding cytoplasm of the host cell and completely covering the band-like proximal portion of the protrusions, which overlapped and were stacked in three to four layers close to the cyst surface. The sarcocyst morphology of S. linearis was consistent with that of an unnamed Sarcocystis sp. in roe deer previously found by transmission electron microscopy in several countries, including Italy. A few Sarcocysts of S. gracilis and S. silva were also examined by SEM, confirming the presence of regularly distributed, short knob-like protrusions in S. gracilis (as seen in previous SEM studies) and revealing tightly packed, erect 6-7-μm-long villus-like protrusions having regularly distributed round depressions on their surface in S. silva. The sequencing of cox1 of 7, 24 and 27 new isolates of S. capreolicanis, S. gracilis and S. silva, respectively, recovered 7, 11 and 10 new haplotypes from each of the three species and expanded our knowledge on the intraspecific sequence variation at this marker. Similarly, the study revealed a more extensive intragenomic sequence variation at the 18S rRNA gene of S. capreolicanis and S. silva than known from previous studies and confirmed a near absence of such variation in the 18S rRNA gene of S. gracilis.
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molecular characterisation of sarcocystis bovifelis sarcocystis bovini n sp sarcocystis hirsuta and sarcocystis cruzi from cattle bos taurus and sarcocystis sinensis from water buffaloes bubalus bubalis
Parasitology Research, 2016Co-Authors: Bjørn GjerdeAbstract:About 200 individual Sarcocysts were excised from 12 samples of cattle beef from five countries (Argentina, Brazil, Germany, New Zealand, Uruguay) and tentatively identified to species or cyst type on the basis of their size and shape and cyst wall morphology. Genomic DNA was extracted from 147 of these Sarcocysts and used initially for PCR amplification and sequencing of the partial mitochondrial cytochrome c oxidase subunit I gene (cox1) in order to identify the Sarcocysts to species and/or sequence type. In addition, seven Sarcocystis sinensis-like Sarcocysts collected from the oesophagus of water buffaloes in Egypt were examined at cox1 for comparative purposes. Based on the results from the cox1 marker, selected sarcocyst isolates from both hosts were further characterised at one to three regions of the nuclear ribosomal (r) DNA unit, i.e. the complete 18S rRNA gene, the complete internal transcribed spacer 1 (ITS1) region and the partial 28S rRNA gene. This was done in order to compare the results with previous molecular identifications based on 18S rRNA gene sequences and to evaluate the utility of these regions for species delimitations and phylogenetic inferences. On the basis of sarcocyst morphology and molecular data, primarily the cox1 sequences, four Sarcocystis spp. were identified in the samples of cattle beef. Twenty-two microscopic Sarcocysts (1 × 0.1 mm) with hair-like protrusions were assigned to Sarcocystis cruzi, 56 macroscopic Sarcocysts (3–8 × 0.5 mm) with finger-like protrusions were assigned to Sarcocystis hirsuta and 45 and 24 microscopic Sarcocysts (1–3 × 0.1–0.2 mm) with finger-like protrusions were assigned to Sarcocystis bovifelis and Sarcocystis bovini n. sp., respectively. Sarcocysts of S. cruzi were identified in samples of beef from Argentina and Uruguay; Sarcocysts of S. hirsuta in samples from Argentina, Brazil, Germany and New Zealand; Sarcocysts of S. bovifelis in samples from Argentina and Germany; and Sarcocysts of S. bovini in samples from Argentina and New Zealand. The microscopic Sarcocysts from water buffaloes were confirmed to belong to S. sinensis. The cox1 sequences of S. bovifelis and S. bovini, respectively, shared an identity of 93–94 % with each other, and these sequences shared an identity of 89–90 % with cox1 of S. sinensis. In contrast, the intraspecific sequence identity was 98.4–100 % (n = 45), 99.3–100 % (n = 24) and 99.5–100 % (n = 7) for sequences of S. bovifelis, S. bovini and S. sinensis, respectively. In each of the latter three species, an aberrant type of cox1 sequences was also identified, which was only 91–92 % identical with the predominant cox1 type of the same species and about 98 % identical with the aberrant types of the two other species. These aberrant cox1 sequences are believed to represent non-functional nuclear copies of the mitochondrial genes (numts or pseudogenes). They might be used as additional markers to separate the three species from each other. Sequencing of a considerable number of clones of S. bovifelis, S. bovini and S. sinensis from each of the three regions of the rDNA unit revealed intraspecific sequence variation in all loci in all species and particularly in the ITS1 locus (78–100 % identity). As regards the 18S rRNA gene, it was possible to separate the three species from each other on the basis of a few consistent nucleotide differences in the less variable 3′ end half of the gene. A comparison of the new sequences with GenBank sequences obtained from S. sinensis-like Sarcocysts in cattle in other studies indicated that previous sequences derived from cattle in Germany and Austria belonged to S. bovifelis, whereas those derived from cattle in China belonged to S. bovini. On the basis of the new 28S rRNA sequences, it was possible to separate S. sinensis from S. bovifelis and S. bovini, whereas the latter two species could not be separated from each other. Based on ITS1 sequences, the three species were indistinguishable. Phylogenetic analysis using maximum parsimony placed with fairly high support cox1 sequences of S. bovifelis, S. bovini and S. sinensis, respectively, into three monophyletic clusters, with S. bovifelis and S. bovini being a sister group to S. sinensis. In contrast, phylogenies based on each of the three regions of the rDNA unit did not separate sequences of the three species completely from each other. Characterisation of cox1 of 56 isolates of S. hirsuta from four countries revealed only 13 haplotypes and an intraspecific sequence identity of 99.3–100 %. In the three regions of the rDNA unit, there was more extensive sequence variation, particularly in the ITS1 region. The 22 cox1 sequences of S. cruzi displayed a moderate intraspecific variation (98.6–100 %), whereas there was no variation at the 18S rRNA gene among 10 sequenced isolates. Sequencing of 16 clones of the partial 28S rRNA gene of S. cruzi yielded two markedly different sequence types, having an overall sequence identity of 95–100 %.
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The resurrection of a species: Sarcocystis bovifelis Heydorn et al., 1975 is distinct from the current Sarcocystis hirsuta in cattle and morphologically indistinguishable from Sarcocystis sinensis in water buffaloes
Parasitology Research, 2016Co-Authors: Bjørn GjerdeAbstract:In the mid-1970s, it was established through transmission experiments and ultrastructural studies of Sarcocysts by transmission electron microscopy (TEM) that cattle was the intermediate host of three Sarcocystis spp. using dogs, cats and humans, respectively, as definitive hosts. The cat-transmitted species with microscopic Sarcocysts was initially named Sarcocystis bovifelis , but it was soon renamed Sarcocystis hirsuta , since it was considered to be identical with a previously named species. In recent years, an apparently new species has been detected in cattle in several countries by molecular methods and TEM and found by both methods to be indistinguishable from Sarcocystis sinensis in water buffaloes. This species was recently named Sarcocystis rommeli . Beginning in August 2014, a thorough review of papers comprising TEM micrographs of thick-walled Sarcocysts in cattle was made in order to determine whether S. sinensis -like Sarcocysts had been reported previously under other designations. Surprisingly, the review showed that the species S. bovifelis Heydorn et al., 1975 as described from cattle in Germany was S. sinensis -like and that indistinguishable Sarcocysts had also been found in cattle in New Zealand and Canada in the 1980s. However, in the New Zealand study, these small Sarcocysts were erroneously thought to represent developmental stages of a species with ultrastructurally similar but macroscopic Sarcocysts, since the macroscopic cysts were found to be infective for cats. Thus, in the late 1980s, the cat-transmitted S. bovifelis , after having been renamed S. hirsuta , was erroneously synonymised with a second cat-transmitted species in cattle and then slid into obscurity until recently being rediscovered as a S. sinensis -like species in cattle and then named S. rommeli . Following the erroneous synonymisation, the name S. hirsuta has consistently been used for a taxon with macroscopic Sarcocysts, and this usage should be continued. The name S. bovifelis should again be used not only for the species originally described from cattle in Germany but also for morphologically indistinguishable taxa recently reported from cattle under the names S. sinensis and S. rommeli . Because of the morphological similarity between S. bovifelis and S. sinensis , it is likely that cats also act as definitive hosts for S. sinensis . The present paper also gives a thorough review of all research in the 1970s pertaining to S. bovifelis , including its development in cats and cattle; a review of reports of S. bovifelis -like Sarcocysts in cattle, water buffaloes and other hosts; and a review of reports of the taxon currently named S. hirsuta in cattle. The usage of the name S. sinensis versus Sarcocystis dubeyi for the S. bovifelis -like taxon in water buffaloes is discussed, and the latter name is found to represent a nomen dubium since the original description concerned a mixture of a S. sinensis - and a Sarcocystis hominis -like species. Based on available transmission (TEM) and scanning electron microscopy (SEM) images, the three-dimensional configuration of the cyst wall protrusions of S. bovifelis / S. sinensis and the current S. hirsuta has been inferred and is described. The protrusions of S. bovifelis / S. sinensis are shaped like soft plastic tubes, having a cylindrical basal portion and a flattened distal portion, making them prone to fold over. The protrusions of the current S. hirsuta are thin, flattened and flexible rectangular structures (like a soft cover note book), which are attached to the cyst surface with a narrow stalk. The appearance of both types of protrusions in ultrathin sections viewed by TEM is highly dependent on how the Sarcocysts and the protrusions themselves have been sectioned.
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Morphological and molecular characteristics of four Sarcocystis spp. in Canadian moose (Alces alces), including Sarcocystis taeniata n. sp.
Parasitology Research, 2014Co-Authors: Bjørn GjerdeAbstract:Individual Sarcocysts were isolated from fresh or alcohol-fixed muscle samples of two moose from Alberta, Canada, and examined by light (LM) and scanning electron microscopy (SEM) and molecular methods, comprising polymerase chain reaction (PCR) amplification and sequencing of the complete18S rRNA gene and the partial cytochrome c oxidase subunit I gene ( cox1 ). By LM, four sarcocyst types were recognized, and the sequencing results showed that each type represented a distinct species, i.e. Sarcocystis alces , Sarcocystis alceslatrans , Sarcocystis ovalis and Sarcocystis taeniata n. sp. The finding of S. alceslatrans and S. ovalis has been reported briefly previously, but further details are provided here, including the ultrastructure of sarcoysts of S. alceslatrans as seen by SEM. The species S. alces was found for the first time in Canadian moose, whereas the finding of S. taeniata is the first record of this species in any host. The Sarcocysts of S. taeniata were sac-like and about 1,000–1,100 × 60–80 μm in size. By LM, the cysts had a thin and smooth wall with no visible protrusions, whereas SEM revealed that the cyst surface had sparsely but regularly distributed, thin ribbon-like protrusions, about 2 μm long and 0.2 μm wide, lying flat against the surface and leaving most of the cyst surface naked. Similar protrusions have previously been reported from Sarcocystis grueneri in reindeer, which was found by sequence comparisons and phylogenetic analyses to be the species most closely related to S. taeniata . The phylogenetic analyses further suggested that S. taeniata , like S. alces and S. alceslatrans , use canids as definitive hosts, whereas corvid birds are known definitive hosts for S. ovalis . In contrast to the three other species found, S. taeniata displayed considerable intra-specific and intra-isolate sequence variation (substitutions, insertions/deletions) in certain regions of the 18S rRNA gene.
Benjamin M Rosenthal - One of the best experts on this subject based on the ideXlab platform.
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sarcocystis strixi n sp from a barred owl strix varia definitive host and interferon gamma gene knockout mice as experimental intermediate host
Journal of Parasitology, 2017Co-Authors: Shiv K. Verma, Joseph Mowery, Benjamin M Rosenthal, J P Dubey, Rosypal A Von Dohlen, D Scott, Camila K Cerqueiracezar, David S LindsayAbstract:Abstract Here we report a new species of Sarcocystis with a barred owl (Strix varia) as the natural definitive host and interferon gamma gene knockout (KO) mice as an experimental intermediate host. A barred owl submitted to the Carolina Raptor Center, Huntersville, North Carolina, was euthanized because of paralysis. Fully sporulated 12.5 × 9.9 μm sporocysts were found in intestinal scrapings from the owl. Sporocysts from the barred owl were orally fed to 4 laboratory-reared outbred Swiss Webster (SW) (Mus musculus) and 8 KO mice. All mice remained asymptomatic. Microscopic Sarcocysts were found in all 5 KO mice euthanized on day 32, 59, 120, 154, and 206 post-inoculation (PI), not in KO mice euthanized on day 4, 8, and 14 PI. Sarcocysts were not found in any SW mice euthanized on day 72, 120, 206, and 210 PI. Sarcocysts were microscopic, up to 70 μm wide. By light microscopy, the sarcocyst wall < 2 μm thick had undulating, flat to conical, protrusions of varying dimensions. Numerous Sarcocysts were seen...
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sarcocystis pantherophisi n sp from eastern rat snakes pantherophis alleghaniensis as definitive hosts and interferon gamma gene knockout mice as experimental intermediate hosts
Journal of Parasitology, 2017Co-Authors: Shiv K. Verma, Joseph Mowery, David S Lindsay, Benjamin M RosenthalAbstract:Abstract Here, we report a new species, Sarcocystis pantherophisi n. sp., with the Eastern rat snake (Pantherophis alleghaniensis) as natural definitive host and the interferon gamma gene knockout (KO) mouse as the experimental intermediate host. Sporocysts (n = 15) from intestinal contents of the snake were 10.8 × 8.9 μm. Sporocysts were orally infective to KO mice but not to laboratory-raised albino outbred house mice (Mus musculus). The interferon gamma KO mice developed schizont-associated neurological signs, and schizonts were cultivated in vitro from the brain. Mature Sarcocysts were found in skeletal muscles of KO mice examined 41 days postinoculation (PI). Sarcocysts were slender, up to 70 μm wide and up to 3.5 mm long. By light microscopy, Sarcocysts appeared thin-walled (<1 μm) without projections. By transmission electron microscopy, the sarcocyst wall was a variant of “type 1” (type 1i, new designation). The parasitophorous vacuolar membrane (pvm) had approximately 100-nm-wide × 100-nm-long bl...
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Morphological and molecular characterization of Sarcocystis arctica-like Sarcocysts from the Arctic fox (Vulpes lagopus) from Alaska, USA
Parasitology Research, 2017Co-Authors: Camila K. Cerqueira-cézar, Joseph Mowery, Rafael Calero-bernal, David R. Sinnett, Shiv Kumar Verma, Peter C. Thompson, Fernando H. Antunes Murata, Caroline Van Hemert, Benjamin M RosenthalAbstract:The muscles of herbivores commonly harbor Sarcocysts of parasites belonging to species in the genus Sarcocystis, but such muscle parasites are rare in carnivores. Here, we report Sarcocystis arctica -like Sarcocysts in muscles of Arctic foxes ( Vulpes lagopus ) from Alaska, USA, for the first time. The tongues of 56 foxes were examined for Sarcocystis infection using several methods. Sarcocystis bradyzoites were detected in pepsin digests of 13 (23.2%), and Sarcocysts were found in histological sections stained with hematoxylin and eosin (HE) of 9 (16.0%). By light microscopy, Sarcocysts were up to 4 mm long and up to 245 μm wide. In HE-stained sections, the sarcocyst wall appeared smooth and up to 1.5 μm thick without visible protrusions. By transmission electron microscopy, the sarcocyst wall had a wavy parasitophorous vacuolar membrane (pvm) folded as pleomorphic villar protrusions (vp), sometimes with anastomoses of villar tips. The vp and the ground substance (gs) layer were smooth and without microtubules. The gs was up to 2.0 μm thick. The total width of the wall including vp and the gs was up to 4.0 μm. The vp were up to 3.0 μm long and most closely resembled “type 9c.” All Sarcocysts were mature and contained numerous 8.1 × 2.1 μm sized bradyzoites. Molecular characterization (at 18S rDNA , 28S rDNA, ITS-1, and cox1) showed the highest affinity for S. arctica of the Arctic fox ( V. lagopus ) from Norway. In the present investigation, we provide evidence that Sarcocysts are common in tongues of Alaskan Arctic foxes suggesting that these carnivores are serving as intermediate hosts, and we also provide ultrastructure of S. arctica from the Arctic fox for the first time.
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molecular characterization and development of sarcocystis speeri Sarcocysts in gamma interferon gene knockout mice
Parasitology, 2015Co-Authors: J P Dubey, Rafael Calerobernal, S K Verma, Detiger Dunams, Benjamin M RosenthalAbstract:The North American opossum (Didelphis virginiana) is the definitive host for at least three named species of Sarcocystis: Sarcocystis falcatula, Sarcocystis neurona and Sarcocystis speeri. The South American opossums (Didelphis albiventris, Didelphis marsupialis and Didelphis aurita) are definitive hosts for S. falcatula and S. lindsayi. The sporocysts of these Sarcocystis species are similar morphologically. They are also not easily distinguished genetically because of the difficulties of DNA extraction from sporocysts and availability of distinguishing genetic markers. Some of these species can be distinguished by bioassay; S. neurona and S. speeri are infective to gamma interferon gene knockout (KO) mice, but not to budgerigars (Melopsittacus undulatus); whereas S. falcatula and S. lindsayi are infective to budgerigars but not to KO mice. The natural intermediate host of S. speeri is unknown. In the present study, development of Sarcocysts of S. speeri in the KO mice is described. Sarcocysts were first seen at 12 days post-inoculation (p.i.), and they became macroscopic (up to 4 mm long) by 25 days p.i. The structure of the sarcocyst wall did not change from the time bradyzoites had formed at 50-220 days p.i. Sarcocysts contained unique villar protrusions, 'type 38'. The polymerase chain reaction amplifications and sequences analysis of three nuclear loci (18S rRNA, 28S rRNA and ITS1) and two mitochondrial loci (cox1 and cytb) of S. speeri isolate from an Argentinean opossum (D. albiventris) confirmed its membership among species of Sarcocystis and indicated an especially close relationship to another parasite in this genus that employs opossums as its definitive host, S. neurona. These results should be useful in finding natural intermediate host of S. speeri.
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experimental transmission of sarcocystis muris apicomplexa sarcocystidae sporocysts from a naturally infected cat felis catus to immunocompetent and immunocompromised mice
Journal of Parasitology, 2013Co-Authors: Yara Alkappany, Benjamin M Rosenthal, M. Hilali, Salah Abuelwafa, D B Dunams, J P DubeyAbstract:Abstract: Cats serve as definitive hosts for zoonotic Toxoplasma gondii, a protozoan that threatens human reproductive health, but they also excrete sporocysts of related protozoan that pose no known human health risk. Here we provide the first definitive evidence for natural infection with the enzootic parasite Sarcocystis muris, one such enzootic parasite. Sporulated Sarcocystis sp. sporocysts were found in rectal contents of an adult feral cat (Felis catus) in Giza, Egypt. After these sporocysts were orally inoculated into 2 Swiss Webster mice, Sarcocysts were found to have developed in skeletal muscles 114 days later. As observed through transmission electron microscopy, the cyst wall corresponded to Type 1, and the parasitophorous vacuolar membrane had tiny outpocketing of blebs (<200 nm thick) that were not invaginated into the interior of the cyst; these structures were identical to the sarcocyst wall described for a Costa Rican isolate of S. muris that has served as an experimental model for near...
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Molecular and morphological description of Sarcocystis kutkienae sp. nov. from the common raven (Corvus corax)
Parasitology Research, 2020Co-Authors: Petras Prakas, Dalius Butkauskas, Evelina Juozaitytė-nguguAbstract:Until now, two Sarcocystis species, S . cornixi and S . corvusi, were known to employ members of the family Corvidae as intermediate hosts. Between 2013 and 2019, having examined leg muscles of 23 common ravens in Lithuania, Sarcocysts were detected in 18 birds (78.3%). Using light microscopy, transmission electron microscopy (TEM), and molecular analysis (three genetic loci, 18S rDNA, 28S rDNA, and ITS1), Sarcocysts found in the common raven were described as a new species S . kutkienae . Under a light microscope, the observed Sarcocysts were ribbon-shaped (1500–8147 × 53–79 μm) and had a wavy striated cyst wall that reached up to 1.5 μm. Lancet-shaped bradyzoites were 7.7 × 2.2 μm (6.1–9.0 × 1.2–3.0 μm) in size. Ultrastructurally, the sarcocyst wall was 1.5–1.8 μm in thickness and had conical-like protrusions with minute invaginations of a parasitophorous vacuolar membrane. The cyst wall was type 1e-like. Limited genetic variability was observed between the 18S rDNA and 28S rDNA sequences of S . kutkienae and other Sarcocystis spp. using birds as intermediate hosts. In contrast, S . kutkienae could be clearly identified by comparing sequences. At this locus, sequences of S . kutkienae shared the highest similarity (89.5–89.7%) with those of S . cornixi . Phylogenetic analysis showed that S. kutkienae was most closely related to Sarcocystis spp. that employs birds as intermediate and definitive hosts. The issue relating to which species might serve as definitive hosts of S . kutkienae in Lithuania is addressed.
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Molecular identification of four Sarcocystis species in the herring gull, Larus argentatus, from Lithuania
Parasites & Vectors, 2020Co-Authors: Petras Prakas, Dalius Butkauskas, Evelina Juozaitytė-nguguAbstract:Background Birds of the family Laridae have not been intensively examined for infections with Sarcocystis spp. To date, Sarcocysts of two species, S . lari and S . wobeseri , have been identified in the muscles of gulls. The aim of the present study was to evaluate the species richness of Sarcocystis in the herring gull, Larus argentatus , from Lithuania. Methods In the period between 2013 and 2019, leg muscles of 35 herring gulls were examined for Sarcocysts of Sarcocystis spp. Sarcocystis spp. were characterised morphologically based on a light microscopy study. Four Sarcocysts isolated from the muscles of each infected bird were subjected to further molecular examination. Sarcocystis species were identified by means of ITS1 sequence analysis. Results Sarcocysts were detected in 9/35 herring gulls (25.7%). Using light microscopy, one morphological type of Sarcocysts was observed. Sarcocysts were microscopic, thread-like, had a smooth and thin (about 1 µm) cyst wall and were filled with banana-shaped bradyzoites. On the basis of ITS1 sequences, four Sarcocystis species, S . columbae , S . halieti , S . lari and S . wobeseri , were identified. Furthermore, it was demonstrated that a single infected herring gull could host two Sarcocystis species indistinguishable under light microscopy. Conclusions Larus argentatus is the first bird species found to act as intermediate host of four Sarcocystis spp. According to current knowledge, five species, S . falcatula , S . calchasi , S . wobeseri , S . columbae and S . halieti can use birds belonging to different orders as intermediate hosts.
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Sarcocystis species identification in the moose (Alces alces) from the Baltic States.
Parasitology research, 2019Co-Authors: Petras Prakas, Eglė Rudaitytė-lukošienė, Rafael Calero-bernal, Viktorija Kirillova, Muza Kirjušina, Miguel A. Habela, Inese Gavarāne, Dalius ButkauskasAbstract:Various muscle tissue samples from 60 moose (Alces alces) in the Baltic region were examined for Sarcocystis species. Sarcocysts were detected in 49 out of 60 (81.7%) moose investigated. Six species, Sarcocystis alces, Sarcocystis hjorti, Sarcocystis linearis, Sarcocystis silva, Sarcocystis ovalis, and Sarcocystis sp., were identified using light microscopy (LM), and DNA sequence analysis (cox1 and 18S rDNA). Sarcocysts of S. alces, S. ovalis, and S. hjorti were studied using transmission electron microscopy (TEM); sarcocyst walls of S. alces, S. ovalis, and S. hjorti were type 25, type 24, and type 7a, respectively. Sarcocystis linearis previously found in roe deer and red deer was also shown to use moose as an intermediate host for the first time. The unknown Sarcocystis sp. was rare and might employ another main intermediate host. Phylogenetic results demonstrated that Sarcocystis sp. was most closely related to Sarcocystis tarandivulpes, using canids as definitive hosts.
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morphologic and genetic identification of sarcocystis fulicae n sp apicomplexa sarcocystidae from the eurasian coot fulica atra
Journal of Wildlife Diseases, 2018Co-Authors: Petras Prakas, Dalius Butkauskas, Saulius Švažas, Evelina Juozaitytėngugu, Vitas StanevičiusAbstract:Abstract One morphologic type of sarcocyst was found in 26% (7/27) of Eurasian Coots (Fulica atra) and was described as Sarcocystis fulicae n. sp. using morphologic, 18S ribosomal (r)DNA, 28S rDNA, and internal transcribed spacer 1 (ITS1) analysis. By light microscope, cysts were ribbon-shaped and measured 7.3 mm in length by 116 μm wide. Histologically, the cyst wall reached up to 1.2 μm in thickness and seemed smooth. The detected Sarcocysts were packed with relatively small banana-shaped bradyzoites that were 6.7×2.0 μm in size. Ultrastructurally, the cyst wall amounted to 1 μm and had many conical protrusions but seemed almost smooth in some places. The parasitophorous vacuolar membrane appeared undulating, with knob-like blebs and invaginations. The cyst wall belonged to type 1d. Morphologically, cysts of S. fulicae differed considerably from cysts of Sarcocystis atraii previously described in the same host but were indistinguishable from those of Sarcocystis corvusi, Sarcocystis lari, and Sarcocysti...
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Morphological and molecular identification of Sarcocystis spp. from the sika deer (Cervus nippon), including two new species Sarcocystis frondea and Sarcocystis nipponi
Parasitology Research, 2018Co-Authors: Eglė Rudaitytė-lukošienė, Liuda Kutkienė, Petras Prakas, Dalius Butkauskas, Iglė Vepštaitė-monstavičė, Elena ServienėAbstract:Diaphragm muscles of 25 sika deer ( Cervus nippon ) farmed in Lithuania were examined for Sarcocysts of Sarcocystis species. Two new Sarcocystis species, Sarcocystis frondea and Sarcocystis nipponi , were observed using light microscopy (LM) and transmission electron microscopy (TEM) and characterized by 18S ribosomal DNA (rDNA) and subunit I of cytochrome c oxidase ( cox1 ) sequence analyses. By LM, Sarcocysts of S . frondea and S . nipponi were ribbon-shaped and had finger-like sarcocyst wall protrusions, respectively. Under TEM, protrusions of S . frondea were about 9 × 1–1.5 μm, filled with clearly visible electron-dense substance and microtubules, type 39-like. Whereas, protrusions (about 9 × 0.2 μm) of S . nipponi arose from dome-shaped bases were filled with microtubules extending to the ground substance layer, type 9o-like. Moreover, three known Sarcocystis spp., Sarcocystis entzerothi , Sarcocystis ovalis , and Sarcocystis truncata previously described in other cervids as intermediate hosts, were characterized in sika deer. The cox1 was more suitable than 18S rDNA delimitating closely related Sarcocystis species from cervids. The phylogenetic results suggest that scavenger birds could be definitive hosts of S . frondea . According to the summarized morphological data on Sarcocystis found in the sika deer, such host should harbor at least nine different Sarcocystis species.
Stina S. Dahlgren - One of the best experts on this subject based on the ideXlab platform.
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molecular characterization of five sarcocystis species in red deer cervus elaphus including sarcocystis hjorti n sp reveals that these species are not intermediate host specific
Parasitology, 2010Co-Authors: Stina S. Dahlgren, Bjørn GjerdeAbstract:Muscle tissue from 37 red deer from Norway was examined for Sarcocysts. Sarcocysts from 2 reindeer were obtained for comparative studies. Cysts were excised and morphologically classified by light microscopy, scanning electron microscopy, and DNA sequence analysis. Five Sarcocystis species, Sarcocystis hjorti n. sp., Sarcocystis hardangeri, Sarcocystis ovalis, Sarcocystis rangiferi, and Sarcocystis tarandi, were found. All 5 species have previously been identified from either reindeer or moose by their sarcocyst morphology and/or ssu rRNA gene sequence. S. hjorti was the most prevalent species. Multiple variants of the ssu rRNA gene and the first internal transcribed spacer were found in S. rangiferi and S. tarandi from both red deer and reindeer. Phylogenetic analyses indicated that S. tarandi occurs in both red deer and reindeer, but it could not be clearly demonstrated whether the sequence variation within S. rangiferi between hosts was due to different paralogues or/and different species. DNA sequencing was necessary for definitive species identification, since the hair-like protrusions on the cysts of S. hjorti were not always recognizable by light microscopy and since different cervids harbour Sarcocystis species with highly similar cyst morphology of which at least some are not intermediate host specific.
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Sarcocystis in Norwegian roe deer (Capreolus capreolus): molecular and morphological identification of Sarcocystis oviformis n. sp. and Sarcocystis gracilis and their phylogenetic relationship with other Sarcocystis species
Parasitology Research, 2008Co-Authors: Stina S. Dahlgren, Bjørn GjerdeAbstract:Fresh muscle tissue from six roe deer from Southeastern Norway was examined for Sarcocysts. Cysts were excised and morphologically classified by light microscopy, and some cysts were further examined by scanning electron microscopy or DNA amplification and sequencing of the small subunit (ssu) rRNA gene. Two Sarcocystis species, Sarcocystis gracilis and Sarcocystis oviformis n. sp., were found and described by morphological and molecular methods. S. gracilis was found in all animals, whereas S. oviformis was found in only one roe deer. Polymerase chain reaction identification was necessary for definitive species identification, since cysts of S. gracilis varied in surface structure and since cysts of both S. gracilis and S. oviformis were morphologically indistinguishable from Sarcocysts in other cervidae. Phylogenetic analyses based on complete ssu rRNA gene sequences revealed a close relationship between S. gracilis and other canine-transmitted Sarcocystis species, whereas S. oviformis formed a well-supported group with Sarcocystis hardangeri of reindeer and Sarcocystis ovalis of moose.
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Sarcocystis in moose (Alces alces): molecular identification and phylogeny of six Sarcocystis species in moose, and a morphological description of three new species
Parasitology Research, 2008Co-Authors: Stina S. Dahlgren, Bjørn GjerdeAbstract:Muscle tissues from 34 moose from Southeastern Norway and two moose from Canada were examined. Sarcocysts were excised and morphologically classified by light microscopy, and some cysts were further examined by scanning electron microscopy or DNA amplification and sequencing at the small subunit (ssu) rRNA gene. In Norwegian moose, three sarcocyst types were recognized, yet five Sarcocystis species were found by sequence analysis. New names were proposed for three species which could be characterised by both morphological and molecular methods, i.e., Sarcocystis alces , Sarcocystis ovalis , and Sarcocystis scandinavica. S. alces was the most prevalent species, whereas S. scandinavica and the two unnamed species were rare and might either use another principal intermediate host or a rare definitive host. The five species in Norwegian moose were different from Sarcocystis alceslatrans isolated from a Canadian moose. Phylogenetic analyses based on complete ssu rRNA gene sequences revealed a close relationship between the six Sarcocystis species from moose and species from reindeer and Sika deer. We conclude that molecular methods are necessary for unequivocal species identification, as different cervid hosts harbour morphologically indistinguishable Sarcocysts.
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morphological and molecular identification of three species of sarcocystis in reindeer rangifer tarandus tarandus in iceland
Veterinary Parasitology, 2007Co-Authors: Stina S. Dahlgren, Bjørn Gjerde, Karl Skirnisson, Berglind GudmundsdottirAbstract:Six Sarcocystis species have previously been described from reindeer in Norway based on sarcocyst morphology and DNA sequencing. The aim of this study was to determine whether reindeer in Iceland, which descend from reindeer imported from Norway in 1787, also were infected with Sarcocystis, and to identify and genetically characterise any species present. Muscle tissue from the heart, diaphragm and/or oesophagus was collected from 36 reindeer in Iceland. Pieces of all tissue samples were examined histologically. Frozen/thawed samples of cardiac muscle, oesophagus and/or diaphragm from 11 of the 36 reindeer were also examined under a stereoscopic microscope and Sarcocysts present were identified to species either in situ or under a light microscope. Two cysts of each species, originating from two different reindeer were randomly selected for DNA analyses. The complete ssu rRNA gene was amplified by the polymerase chain reaction (PCR) and sequenced. In addition, two Sarcocysts that could not be classified by microscopic examination were selected for partial ssu rRNA gene sequence analysis. By histology, Sarcocysts were found in the diaphragm and/or oesophagus of 8 of 36 (22.2%) animals. By examination of fresh tissue, Sarcocysts of Sarcocystis rangi, S. tarandivulpes and S. hardangeri were found in the oesophagus of seven of nine (77.8%) animals, suggesting a high prevalence of Sarcocystis in the Icelandic reindeer population. Cyst morphology and the ssu rRNA gene sequence of each of the three species were identical to isolates of the same species from Norwegian reindeer. DNA sequencing was useful in order to identify cysts with an ambiguous morphology. This is the first record of these Sarcocystis species in reindeer outside Norway.
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genetic characterisation of six sarcocystis species from reindeer rangifer tarandus tarandus in norway based on the small subunit rrna gene
Veterinary Parasitology, 2007Co-Authors: Stina S. Dahlgren, Bjørn GjerdeAbstract:Six Sarcocystis species, i.e. Sarcocystis grueneri, Sarcocystis rangi, Sarcocystis tarandivulpes, Sarcocystis hardangeri, Sarcocystis rangiferi and Sarcocystis tarandi have previously been described from reindeer based on sarcocyst morphology. In order to validate and expand the species descriptions, the complete small subunit (ssu) rRNA gene was sequenced and used to genetically characterise the six species. The aim was to reveal possible genetic variation in the ssu rRNA gene within each Sarcocystis species, between the species from reindeer, but also between the reindeer species and related Sarcocystis species characterised in other studies. Muscle tissue from the heart and diaphragm was sampled from 18 adult semi-domesticated reindeer at a field abattoir in northern Norway. Sarcocysts were excised from the tissue and classified into one of the six known Sarcocystis species based on their morphology. Two cysts of each of the six species from two different animals were randomly selected for further DNA analyses. The complete ssu rRNA gene was amplified by the polymerase chain reaction (PCR) and subsequently sequenced. The complete ssu rRNA gene sequences were used to compare the six species with each other and with other previously sequenced Sarcocystis species retrieved from GenBank. There was little sequence variation between two isolates of the same species, but the six species differed from each other by insertions, deletions and single nucleotide polymorphisms (SNPs), mainly located in variable regions of the gene. The identity between the six species from reindeer was approximately the same as when other Sarcocystis species using a different intermediate host were compared with each other. This study supported previous findings of reindeer being the intermediate host for at least six Sarcocystis species and the results also indicated the existence of certain nucleotide positions within the ssu rRNA gene that are unique to Sarcocystis species with a canine definitive host.
