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Achim D Gruber - One of the best experts on this subject based on the ideXlab platform.
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Accipiter hawks ( Accipitridae ) confirmed as definitive hosts of Sarcocystis turdusi , Sarcocystis cornixi and Sarcocystis sp. ex Phalacrocorax carbo
Parasitology research, 2016Co-Authors: Sylvia L. Mayr, Achim D Gruber, Kristina Maier, Jana Müller, Dirk Enderlein, Michael LierzAbstract:Sarcocystis is a large genus of protozoan parasites with complex heteroxenous life cycles. For many species, either the intermediate or the definitive host is still unknown. In this study, 116 Accipiter hawks (Eurasian sparrowhawks and northern goshawks) were investigated for the presence of Sarcocystis spp. in their intestinal tract or their faeces. To gain a wide distribution, samples were collected throughout Germany within 2 years. It was possible to detect Sarcocystis-like oocysts in 65 samples. Sequencing of the ITS region or species-specific PCR identified 33 samples as Sarcocystis turdusi/Sarcocystis sp. ex A. nisus (18), Sarcocystis calchasi (6), Sarcocystis columbae (3), Sarcocystis cornixi (3) and Sarcocystis sp. ex Phalacrocorax carbo (3). Besides the known infestation with S. columbae, S. sp. ex A. nisus and S. calchasi the Accipiter hawks were thereby confirmed as definitive host of S. turdusi, S. cornixi and S. sp. ex Phalacrocorax carbo for the first time.
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high prevalence of sarcocystis calchasi sporocysts in european Accipiter hawks
Veterinary Parasitology, 2011Co-Authors: Philipp Olias, Lena Olias, Michael Lierz, Jurgen Krucken, Achim D GruberAbstract:The emerging Sarcocystis calchasi induces a severe and lethal central nervous disease in its intermediate host, the domestic pigeon (Columba livia f. domestica). Experimental studies have identified the Northern goshawk (Accipiter g. gentilis) as final host. Phylogenetically closely related European sparrowhawks (Accipiter n. nisus) and wood pigeons (Columba palumbus) have been found to harbor genetically closely related Sarcocystis spp. However, data on the prevalence and potential interspecies occurrence of these parasites are lacking. Here, we report that European Accipiter hawks (Accipitrinae) are highly infected with S. calchasi, S. columbae and Sarcocystis sp. ex A. nisus in their small intestine. Thirty-one of 50 (62%) Northern goshawks necropsied during 1997-2008 were positive for S. calchasi in a newly established species-specific semi-nested PCR assay based on the first internal transcribed spacer region. Unexpectedly, 14 of 20 (71.4%) European sparrowhawks tested also positive. In addition, birds of both species were found to be infested with S. columbae and an, as yet, unnamed Sarcocystis sp. recently isolated from European sparrowhawks. These findings raise new questions about the host specificity of S. calchasi and its high virulence in domestic pigeons, since sparrowhawks only rarely prey on pigeons. Notably, isolated sporocysts from both infected Accipiter spp. measured 8 μm × 11.9 μm, precluding a preliminary identification of S. calchasi in feces of Accipiter hawks based on morphology alone. Importantly, three of four Northern goshawks used in falconry tested positive for S. calchasi. In conclusion, the results indicate that both European Accipter spp. in Germany serve as natural final hosts of S. calchasi and suggest that falconry and pigeon sport may serve as risk factors for the spread of this pathogen in domestic pigeons.
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sarcocystis calchasi is distinct to sarcocystis columbae sp nov from the wood pigeon columba palumbus and sarcocystis sp from the sparrowhawk Accipiter nisus
Veterinary Parasitology, 2010Co-Authors: Philipp Olias, Lena Olias, Michael Lierz, Heinz Mehlhorn, Achim D GruberAbstract:Abstract Sarcocystis calchasi has been identified as causative agent of a newly discovered central nervous disease in domestic pigeons ( Columba livia f. domestica ) observed for the first time in Germany in 2006. Initial studies have indicated that this parasite is highly pathogenic for domestic pigeons after ingestion of low doses of sporocysts shed by the Northern goshawk ( Accipiter gentilis ). Here we tested whether phylogenetically related birds might regularly harbor Sarcocystis species. Five wood pigeons ( Columba palumbus ) and five sparrowhawks ( Accipiter nisus ) from Northern Germany were examined. All birds were PCR negative for S. calchasi by universal primers. Instead, both avian species harbored two as yet undescribed Sarcocystis species. Light and transmission electron microscopy identified cysts in the skeletal muscle of wood pigeons of 56–156 μm in width. The cysts had a smooth surface without protrusions. Sporocysts derived from the small intestine of the sparrowhawks measured 11.88 μm × 8.34 μm. Polymerase chain reaction amplification and sequencing of the first internal transcribed spacer region (ITS-1), the 18S rRNA and the 28S rRNA gene comprising the variabel D2 and D3 domains further characterized them as two novel Sarcocystis species. S. calchasi displays a pairwise distance value of the ITS-1 region ranging between 0.165 and 0.195 with the Sarcocystis spp. from the wood pigeon and the sparrowhawk, respectively. A phylogenetic analysis further supported the existence of two new species.
Michael Lierz - One of the best experts on this subject based on the ideXlab platform.
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Accipiter hawks ( Accipitridae ) confirmed as definitive hosts of Sarcocystis turdusi , Sarcocystis cornixi and Sarcocystis sp. ex Phalacrocorax carbo
Parasitology research, 2016Co-Authors: Sylvia L. Mayr, Achim D Gruber, Kristina Maier, Jana Müller, Dirk Enderlein, Michael LierzAbstract:Sarcocystis is a large genus of protozoan parasites with complex heteroxenous life cycles. For many species, either the intermediate or the definitive host is still unknown. In this study, 116 Accipiter hawks (Eurasian sparrowhawks and northern goshawks) were investigated for the presence of Sarcocystis spp. in their intestinal tract or their faeces. To gain a wide distribution, samples were collected throughout Germany within 2 years. It was possible to detect Sarcocystis-like oocysts in 65 samples. Sequencing of the ITS region or species-specific PCR identified 33 samples as Sarcocystis turdusi/Sarcocystis sp. ex A. nisus (18), Sarcocystis calchasi (6), Sarcocystis columbae (3), Sarcocystis cornixi (3) and Sarcocystis sp. ex Phalacrocorax carbo (3). Besides the known infestation with S. columbae, S. sp. ex A. nisus and S. calchasi the Accipiter hawks were thereby confirmed as definitive host of S. turdusi, S. cornixi and S. sp. ex Phalacrocorax carbo for the first time.
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high prevalence of sarcocystis calchasi sporocysts in european Accipiter hawks
Veterinary Parasitology, 2011Co-Authors: Philipp Olias, Lena Olias, Michael Lierz, Jurgen Krucken, Achim D GruberAbstract:The emerging Sarcocystis calchasi induces a severe and lethal central nervous disease in its intermediate host, the domestic pigeon (Columba livia f. domestica). Experimental studies have identified the Northern goshawk (Accipiter g. gentilis) as final host. Phylogenetically closely related European sparrowhawks (Accipiter n. nisus) and wood pigeons (Columba palumbus) have been found to harbor genetically closely related Sarcocystis spp. However, data on the prevalence and potential interspecies occurrence of these parasites are lacking. Here, we report that European Accipiter hawks (Accipitrinae) are highly infected with S. calchasi, S. columbae and Sarcocystis sp. ex A. nisus in their small intestine. Thirty-one of 50 (62%) Northern goshawks necropsied during 1997-2008 were positive for S. calchasi in a newly established species-specific semi-nested PCR assay based on the first internal transcribed spacer region. Unexpectedly, 14 of 20 (71.4%) European sparrowhawks tested also positive. In addition, birds of both species were found to be infested with S. columbae and an, as yet, unnamed Sarcocystis sp. recently isolated from European sparrowhawks. These findings raise new questions about the host specificity of S. calchasi and its high virulence in domestic pigeons, since sparrowhawks only rarely prey on pigeons. Notably, isolated sporocysts from both infected Accipiter spp. measured 8 μm × 11.9 μm, precluding a preliminary identification of S. calchasi in feces of Accipiter hawks based on morphology alone. Importantly, three of four Northern goshawks used in falconry tested positive for S. calchasi. In conclusion, the results indicate that both European Accipter spp. in Germany serve as natural final hosts of S. calchasi and suggest that falconry and pigeon sport may serve as risk factors for the spread of this pathogen in domestic pigeons.
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sarcocystis calchasi is distinct to sarcocystis columbae sp nov from the wood pigeon columba palumbus and sarcocystis sp from the sparrowhawk Accipiter nisus
Veterinary Parasitology, 2010Co-Authors: Philipp Olias, Lena Olias, Michael Lierz, Heinz Mehlhorn, Achim D GruberAbstract:Abstract Sarcocystis calchasi has been identified as causative agent of a newly discovered central nervous disease in domestic pigeons ( Columba livia f. domestica ) observed for the first time in Germany in 2006. Initial studies have indicated that this parasite is highly pathogenic for domestic pigeons after ingestion of low doses of sporocysts shed by the Northern goshawk ( Accipiter gentilis ). Here we tested whether phylogenetically related birds might regularly harbor Sarcocystis species. Five wood pigeons ( Columba palumbus ) and five sparrowhawks ( Accipiter nisus ) from Northern Germany were examined. All birds were PCR negative for S. calchasi by universal primers. Instead, both avian species harbored two as yet undescribed Sarcocystis species. Light and transmission electron microscopy identified cysts in the skeletal muscle of wood pigeons of 56–156 μm in width. The cysts had a smooth surface without protrusions. Sporocysts derived from the small intestine of the sparrowhawks measured 11.88 μm × 8.34 μm. Polymerase chain reaction amplification and sequencing of the first internal transcribed spacer region (ITS-1), the 18S rRNA and the 28S rRNA gene comprising the variabel D2 and D3 domains further characterized them as two novel Sarcocystis species. S. calchasi displays a pairwise distance value of the ITS-1 region ranging between 0.165 and 0.195 with the Sarcocystis spp. from the wood pigeon and the sparrowhawk, respectively. A phylogenetic analysis further supported the existence of two new species.
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Pathogenicity of Mycoplasma lipofaciens strain ML64, isolated from an egg of a Northern Goshawk (Accipiter gentilis), for chicken embryos
Avian pathology : journal of the W.V.P.A, 2007Co-Authors: Michael Lierz, R. Stark, Sebastian Brokat, Hafez M HafezAbstract:Some Mycoplasma species are well-known avian pathogens and are of importance in poultry breeder flocks due to their pathogenic potential for embryos. Mycoplasmas are regularly detected in birds of prey, and a strain of Mycoplasma lipofaciens that was isolated from an egg of a Northern Goshawk (Accipiter gentilis) was examined for its pathogenicity in specific pathogen free chicken embryos since birds of prey eggs were not available for this purpose. The strain was found to be pathogenic, causing a high mortality as well as dwarfing, curled toes and infiltrations of heterophils in the liver, kidney, intestine and chorioallantoic membrane.
Martin Tomesek - One of the best experts on this subject based on the ideXlab platform.
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mortality of goshawks Accipiter gentilis due to west nile virus lineage 2
Vector-borne and Zoonotic Diseases, 2018Co-Authors: Zdenek Hubalek, Marcel Kosina, Ivo Rudolf, Jan Mendel, Petra Strakova, Martin TomesekAbstract:In 2017, we isolated and identified West Nile virus (WNV) lineage 2 from two dead captive goshawks (Accipiter gentilis), for the first time in the Czech Republic. Goshawk might serve as an early indicator species for the ongoing WNV emergence in several European countries.
Philipp Olias - One of the best experts on this subject based on the ideXlab platform.
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high prevalence of sarcocystis calchasi sporocysts in european Accipiter hawks
Veterinary Parasitology, 2011Co-Authors: Philipp Olias, Lena Olias, Michael Lierz, Jurgen Krucken, Achim D GruberAbstract:The emerging Sarcocystis calchasi induces a severe and lethal central nervous disease in its intermediate host, the domestic pigeon (Columba livia f. domestica). Experimental studies have identified the Northern goshawk (Accipiter g. gentilis) as final host. Phylogenetically closely related European sparrowhawks (Accipiter n. nisus) and wood pigeons (Columba palumbus) have been found to harbor genetically closely related Sarcocystis spp. However, data on the prevalence and potential interspecies occurrence of these parasites are lacking. Here, we report that European Accipiter hawks (Accipitrinae) are highly infected with S. calchasi, S. columbae and Sarcocystis sp. ex A. nisus in their small intestine. Thirty-one of 50 (62%) Northern goshawks necropsied during 1997-2008 were positive for S. calchasi in a newly established species-specific semi-nested PCR assay based on the first internal transcribed spacer region. Unexpectedly, 14 of 20 (71.4%) European sparrowhawks tested also positive. In addition, birds of both species were found to be infested with S. columbae and an, as yet, unnamed Sarcocystis sp. recently isolated from European sparrowhawks. These findings raise new questions about the host specificity of S. calchasi and its high virulence in domestic pigeons, since sparrowhawks only rarely prey on pigeons. Notably, isolated sporocysts from both infected Accipiter spp. measured 8 μm × 11.9 μm, precluding a preliminary identification of S. calchasi in feces of Accipiter hawks based on morphology alone. Importantly, three of four Northern goshawks used in falconry tested positive for S. calchasi. In conclusion, the results indicate that both European Accipter spp. in Germany serve as natural final hosts of S. calchasi and suggest that falconry and pigeon sport may serve as risk factors for the spread of this pathogen in domestic pigeons.
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sarcocystis calchasi is distinct to sarcocystis columbae sp nov from the wood pigeon columba palumbus and sarcocystis sp from the sparrowhawk Accipiter nisus
Veterinary Parasitology, 2010Co-Authors: Philipp Olias, Lena Olias, Michael Lierz, Heinz Mehlhorn, Achim D GruberAbstract:Abstract Sarcocystis calchasi has been identified as causative agent of a newly discovered central nervous disease in domestic pigeons ( Columba livia f. domestica ) observed for the first time in Germany in 2006. Initial studies have indicated that this parasite is highly pathogenic for domestic pigeons after ingestion of low doses of sporocysts shed by the Northern goshawk ( Accipiter gentilis ). Here we tested whether phylogenetically related birds might regularly harbor Sarcocystis species. Five wood pigeons ( Columba palumbus ) and five sparrowhawks ( Accipiter nisus ) from Northern Germany were examined. All birds were PCR negative for S. calchasi by universal primers. Instead, both avian species harbored two as yet undescribed Sarcocystis species. Light and transmission electron microscopy identified cysts in the skeletal muscle of wood pigeons of 56–156 μm in width. The cysts had a smooth surface without protrusions. Sporocysts derived from the small intestine of the sparrowhawks measured 11.88 μm × 8.34 μm. Polymerase chain reaction amplification and sequencing of the first internal transcribed spacer region (ITS-1), the 18S rRNA and the 28S rRNA gene comprising the variabel D2 and D3 domains further characterized them as two novel Sarcocystis species. S. calchasi displays a pairwise distance value of the ITS-1 region ranging between 0.165 and 0.195 with the Sarcocystis spp. from the wood pigeon and the sparrowhawk, respectively. A phylogenetic analysis further supported the existence of two new species.
Darren E. Irwin - One of the best experts on this subject based on the ideXlab platform.
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Population genomic analyses reveal a highly differentiated and endangered genetic cluster of northern goshawks (Accipiter gentilis laingi) in Haida Gwaii.
Evolutionary applications, 2019Co-Authors: Armando Geraldes, Frank I. Doyle, William L. Harrower, Kenneth K. Askelson, Ellen Nikelski, Kevin Winker, Darren E. IrwinAbstract:Accurate knowledge of geographic ranges and genetic relationships among populations is important when managing a species or population of conservation concern. Along the western coast of Canada, a subspecies of the northern goshawk (Accipiter gentilis laingi) is legally designated as Threatened. The range and distinctness of this form, in comparison with the broadly distributed North American subspecies (Accipiter gentilis atricapillus), is unclear. Given this morphological uncertainty, we analyzed genomic relationships in thousands of single nucleotide polymorphisms identified using genotyping-by-sequencing of high-quality genetic samples. Results revealed a genetically distinct population of northern goshawks on the archipelago of Haida Gwaii and subtle structuring among other North American sampling regions. We then developed genotyping assays for ten loci that are highly differentiated between the two main genetic clusters, allowing inclusion of hundreds of low-quality samples and confirming that the distinct genetic cluster is restricted to Haida Gwaii. As the laingi form was originally described as being based on Haida Gwaii (where the type specimen is from), further morphological analysis may result in this name being restricted to the Haida Gwaii genetic cluster. Regardless of taxonomic treatment, the distinct Haida Gwaii genetic cluster along with the small and declining population size of the Haida Gwaii population suggests a high risk of extinction of an ecologically and genetically distinct form of northern goshawk. Outside of Haida Gwaii, sampling regions along the coast of BC and southeast Alaska (often considered regions inhabited by laingi) show some subtle differentiation from other North American regions. These results will increase the effectiveness of conservation management of northern goshawks in northwestern North America. More broadly, other conservation-related studies of genetic variation may benefit from the two-step approach we employed that first surveys genomic variation using high-quality samples and then genotypes low-quality samples at particularly informative loci.
