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Gediminas Valkiūnas - One of the best experts on this subject based on the ideXlab platform.
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Patterns of Haemoproteus majoris (Haemosporida, Haemoproteidae) megalomeront development.
Acta tropica, 2020Co-Authors: Mélanie Duc, Mikas Ilgūnas, Gediminas ValkiūnasAbstract:Abstract Blood parasites of the genus Haemoproteus (Haemosporida, Haemoproteidae) are cosmopolitan and prevalent in birds. Numerous species and lineages of these pathogens have been identified. Some of the infections are lethal in avian hosts mainly due to damage of organs by tissue stages, which remain insufficiently investigated. Several closely related lineages of Haemoproteus majoris, a common parasite of passeriform birds, have been identified. One recent study described megalomeronts of unique morphology in the lineages hPHYBOR04 and hPARUS1 of H. majoris and suggested that the similar tissues stages might also be features in other phylogenetically closely related lineages of the same parasite species. This study aimed to test if (i) megalomeronts are present during the development of the lineage hPHSIB1 of H. majoris and if (ii) they are similar to the other investigated lineages of this species in regard of their morphology and location in organs. One adult wood warbler Phylloscopus sibilatrix, an Afrotropical migrant, naturally infected with H. majoris lineage hPHSIB1 was wild-caught after seasonal spring migration and screened using microscopic examination of blood films and histological sections of organs as well as using PCR-based testing. Bayesian phylogenetic analysis placed the lineages hPHSIB1, hPHYBOR04 and hPARUS1 in one, well-supported clade. Parasitaemia was high (6.5%) in the examined wood warbler, numerous megalomeronts were found in kidneys, and a few in the intestine. Megalomeronts of the lineage hPHSIB1 were morphologically hardly distinguishable from those of lineages hPHYBOR04 and hPARUS1; only negligible differences in the maturation stage of the cytomeres were seen. The kidneys were the main location site of the megalomeronts in all three lineages of this parasite species. This study shows that closely related lineages of H. majoris produce megalomeronts of similar morphology and predominant location in kidneys, while the normal function of this organ may be affected by the presence of numerous large megalomeronts. Megalomeronts of different avian Haemoproteus species are markedly variable in morphology and location, but phylogenetically closely related lineages possess cryptic megalomeronts. This finding suggests that phylogenies based on partial cytb gene could provide information for prediction of patterns of exo-erythrocytic development of closely related Haemoproteus parasites and are worthy of attention in planning haemosporidian parasite tissue stage research.
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Description of Haemoproteus ciconiae sp. nov. (Haemoproteidae, Haemosporida) from the white stork Ciconia ciconia, with remarks on insensitivity of established polymerase chain reaction assays to detect this infection
Parasitology Research, 2016Co-Authors: Gediminas Valkiūnas, Mikas Ilgūnas, Dovilė Bukauskaitė, Tatjana A. IezhovaAbstract:Haemoproteus ciconiae sp. nov. (Haemosporida, Haemoproteidae) was found in the white stork Ciconia ciconia (Ciconiiformes, Ciconiidae) after spring migration in Lithuania. This organism is illustrated and described based on the morphology of its blood stages. The new species can be readily distinguished from all other haemoproteids parasitizing ciconiiform birds due to the presence of large number (approximately 20 on average) small (
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Recent advances in vector studies of avian haemosporidian parasites
Ekologija, 2015Co-Authors: Rita Žiegytė, Gediminas ValkiūnasAbstract:Many recent studies addressed morphological and molecular characterization, distribution, genetic diversity and evolutionary relationships of avian haemosporidian parasites (Haemosporida). However, the information about relationships between bird haemosporidians and their vectors remains fragmentary and scarce. Experimental studies on this subject are few. Recent advances in vector research of avian haemosporidians (Haemosporida) have been briefly reviewed in regard to the experimental studies, which have been carried out at the Nature Research Centre, Vilnius, during the last five years, with particular attention to widespread species of Plasmodium and Haemoproteus parasites. New information about vectors of avian malaria parasites and haemoproteids is provided and discussed. We point out high virulence of widespread Haemoproteus species for bloodsucking insects of the Culicidae and Ceratopogonidae, and call for additional studies on this subject. Due to widespread abortive sporogonic development in bloodsucking insects, Polymerase Chain Reaction (PCR)-based diagnostics should be carefully used in vector research of haemosporidians because it detects parasites in blood-sucking insects for several weeks after initial infection, but does not distinguish abortive parasite development. That questions vector studies, which are based solely on PCR-based tools. Demonstration of infective sporozoites in insects is essential for definitively demonstrating the insects are vectors. Because of the complicated life cycles of haemosporidians, microscopic approaches and experimental research remain essential and should be applied in parallel with PCRbased detection tools in vector studies, particularly in wildlife.
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In vitro development of Haemoproteus parasites: the efficiency of reproductive cells increase during simultaneous sexual process of different lineages.
Parasitology Research, 2014Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Mikas Ilgūnas, Rasa Bernotienė, Tatjana A. IezhovaAbstract:Recent in vitro experimental studies reported the complex patterns of haemosporidian (Haemosporida) between-lineage interactions, which prevent mixing of lineages during simultaneous sexual process. Numerous anomalous ookinetes have been observed; these are not involved in sporogony. Massive development of such ookinetes might influence parasite transmission but is insufficiently investigated. The simultaneous sexual process of several lineages is a common phenomenon in vectors due to high prevalence of haemosporidian co-infections in wildlife. It remains unclear if the number of anomalous ookinetes changes during dual-infection sporogony in comparison with the single-infection process. We calculated proportions of the anomalous and normal ookinetes, which developed during single-infection (control) and dual-infection experiments in vitro conditions. Three mitochondrial cytochrome b lineages belonging to three Haemoproteus spp. (Haemosporida, Haemoproteidae) were isolated from naturally infected passerine birds. Sexual process and ookinete development were initiated in vitro by mixing blood containing mature gametocytes of two different parasites; the following experiments were performed: (1) Haemoproteus tartakovskyi (lineage hSISKIN1) × Haemoproteus lanii (lineage hRBS4) and (2) Haemoproteus belopolskyi (hHIICT3) × H. lanii (hRBS4). Genetic difference between lineages was 5.0–5.9 %. Normal and anomalous ookinetes developed in all control and dual-infection experiments. The number of anomalous ookinetes markedly decreased, and normal ookinetes increased in all dual-infection experiments in comparison with those in controls, except for H. belopolskyi, in which proportion of the anomalous and normal ookinetes did not change. This study shows that simultaneous sexual process of two genetically distant lineages of haemosporidian parasites might increase the efficiency of reproductive cells, resulting in the development of a greater number of normal ookinetes. The marked increase of the number of normal ookinetes, which is involved in sporogony, indicates the success of sporogony in dual infections. Some haemosporidian lineages might benefit from simultaneous sporogony. Widespread avian Haemoproteus spp. are convenient and laboratory-friendly organisms for in vitro experimental research addressing between-lineage interaction in parasites during the sexual process.
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Haemoproteus infections (Haemosporida, Haemoproteidae) kill bird-biting mosquitoes
Parasitology research, 2013Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Rasa Bernotienė, Dovilė Bukauskaitė, Rita Kazlauskienė, Tatjana A. IezhovaAbstract:Haemoproteus parasites (Haemosporida, Haemoproteidae) are widespread; some species cause severe diseases in avian hosts. Heavy Haemoproteus infections are often lethal for biting midges (Ceratopogonidae), which transmit avian haemoproteids, but there is no information regarding detrimental effect on other blood-sucking insects. We examined effects of Haemoproteus tartakovskyi (lineage hSISKIN1), Haemoproteus lanii (lineages hRB1and hRBS2) and Haemoproteus balmorali (lineage hCOLL3) on the survival of Ochlerotatus cantans, a widespread Eurasian mosquito. Wild-caught females were infected by allowing them to feed on naturally infected birds with light (0.01 %) and high (3.0–9.6 %) parasitaemia. Mosquitoes fed on uninfected birds were used as controls. Both experimental and control groups were maintained under the same laboratory conditions until 20 days post-exposure (dpe). Dead insects were counted daily and used for parasitological examination and PCR-based testing. No difference was discernible in the survival rate of control mosquitoes and those fed on meal with light parasitaemia. There was a highly significant difference in the survival rate between the control group and all groups fed on meals with high parasitaemia, with the greatest mortality reported 1–3 dpe. For 4 dpe, the percentage of survived control mosquitoes (88 %) was 2.2-, 3.6- and 4-fold greater than that of groups fed on meals with high parasitaemia of H. balmorali, H. tartakovskyi and H. lanii, respectively. Numerous ookinetes were observed in the gut area and adjacent tissues located in the head, thorax and abdomen of infected insects 0.5–1 dpe. The migrating parasites damage organs throughout the entire body of mosquitoes; that is the main reason of mortality. To the end of this study, 46 % of mosquitoes survived in control group, but the survival rates of experimental mosquitoes fed on meals with high parasitaemia were between 2.6- and 5.8-fold lower. This study indicates that widespread Haemoproteus infections are markedly virulent for bird-biting mosquitoes, which rapidly die after feeding on heavily infected blood meals.
Tatjana A. Iezhova - One of the best experts on this subject based on the ideXlab platform.
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TERMS
2016Co-Authors: Asta Križanauskienė, Tatjana A. Iezhova, Ravinder N. M. Sehgal, Jenny S. CarlsonAbstract:http://zoobank.org/urn:lsid:zoobank.org:pub:185632F5-8CA8-4BFF-B9F0-401DF00EF0AF Molecular characterization of Haemoproteus sacharovi (Haemosporida, Haemoproteidae), a common parasite of columbiform birds, with remarks on classification of haemoproteids of doves and pigeon
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Description of Haemoproteus ciconiae sp. nov. (Haemoproteidae, Haemosporida) from the white stork Ciconia ciconia, with remarks on insensitivity of established polymerase chain reaction assays to detect this infection
Parasitology Research, 2016Co-Authors: Gediminas Valkiūnas, Mikas Ilgūnas, Dovilė Bukauskaitė, Tatjana A. IezhovaAbstract:Haemoproteus ciconiae sp. nov. (Haemosporida, Haemoproteidae) was found in the white stork Ciconia ciconia (Ciconiiformes, Ciconiidae) after spring migration in Lithuania. This organism is illustrated and described based on the morphology of its blood stages. The new species can be readily distinguished from all other haemoproteids parasitizing ciconiiform birds due to the presence of large number (approximately 20 on average) small (
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In vitro development of Haemoproteus parasites: the efficiency of reproductive cells increase during simultaneous sexual process of different lineages.
Parasitology Research, 2014Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Mikas Ilgūnas, Rasa Bernotienė, Tatjana A. IezhovaAbstract:Recent in vitro experimental studies reported the complex patterns of haemosporidian (Haemosporida) between-lineage interactions, which prevent mixing of lineages during simultaneous sexual process. Numerous anomalous ookinetes have been observed; these are not involved in sporogony. Massive development of such ookinetes might influence parasite transmission but is insufficiently investigated. The simultaneous sexual process of several lineages is a common phenomenon in vectors due to high prevalence of haemosporidian co-infections in wildlife. It remains unclear if the number of anomalous ookinetes changes during dual-infection sporogony in comparison with the single-infection process. We calculated proportions of the anomalous and normal ookinetes, which developed during single-infection (control) and dual-infection experiments in vitro conditions. Three mitochondrial cytochrome b lineages belonging to three Haemoproteus spp. (Haemosporida, Haemoproteidae) were isolated from naturally infected passerine birds. Sexual process and ookinete development were initiated in vitro by mixing blood containing mature gametocytes of two different parasites; the following experiments were performed: (1) Haemoproteus tartakovskyi (lineage hSISKIN1) × Haemoproteus lanii (lineage hRBS4) and (2) Haemoproteus belopolskyi (hHIICT3) × H. lanii (hRBS4). Genetic difference between lineages was 5.0–5.9 %. Normal and anomalous ookinetes developed in all control and dual-infection experiments. The number of anomalous ookinetes markedly decreased, and normal ookinetes increased in all dual-infection experiments in comparison with those in controls, except for H. belopolskyi, in which proportion of the anomalous and normal ookinetes did not change. This study shows that simultaneous sexual process of two genetically distant lineages of haemosporidian parasites might increase the efficiency of reproductive cells, resulting in the development of a greater number of normal ookinetes. The marked increase of the number of normal ookinetes, which is involved in sporogony, indicates the success of sporogony in dual infections. Some haemosporidian lineages might benefit from simultaneous sporogony. Widespread avian Haemoproteus spp. are convenient and laboratory-friendly organisms for in vitro experimental research addressing between-lineage interaction in parasites during the sexual process.
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Haemoproteus infections (Haemosporida, Haemoproteidae) kill bird-biting mosquitoes
Parasitology research, 2013Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Rasa Bernotienė, Dovilė Bukauskaitė, Rita Kazlauskienė, Tatjana A. IezhovaAbstract:Haemoproteus parasites (Haemosporida, Haemoproteidae) are widespread; some species cause severe diseases in avian hosts. Heavy Haemoproteus infections are often lethal for biting midges (Ceratopogonidae), which transmit avian haemoproteids, but there is no information regarding detrimental effect on other blood-sucking insects. We examined effects of Haemoproteus tartakovskyi (lineage hSISKIN1), Haemoproteus lanii (lineages hRB1and hRBS2) and Haemoproteus balmorali (lineage hCOLL3) on the survival of Ochlerotatus cantans, a widespread Eurasian mosquito. Wild-caught females were infected by allowing them to feed on naturally infected birds with light (0.01 %) and high (3.0–9.6 %) parasitaemia. Mosquitoes fed on uninfected birds were used as controls. Both experimental and control groups were maintained under the same laboratory conditions until 20 days post-exposure (dpe). Dead insects were counted daily and used for parasitological examination and PCR-based testing. No difference was discernible in the survival rate of control mosquitoes and those fed on meal with light parasitaemia. There was a highly significant difference in the survival rate between the control group and all groups fed on meals with high parasitaemia, with the greatest mortality reported 1–3 dpe. For 4 dpe, the percentage of survived control mosquitoes (88 %) was 2.2-, 3.6- and 4-fold greater than that of groups fed on meals with high parasitaemia of H. balmorali, H. tartakovskyi and H. lanii, respectively. Numerous ookinetes were observed in the gut area and adjacent tissues located in the head, thorax and abdomen of infected insects 0.5–1 dpe. The migrating parasites damage organs throughout the entire body of mosquitoes; that is the main reason of mortality. To the end of this study, 46 % of mosquitoes survived in control group, but the survival rates of experimental mosquitoes fed on meals with high parasitaemia were between 2.6- and 5.8-fold lower. This study indicates that widespread Haemoproteus infections are markedly virulent for bird-biting mosquitoes, which rapidly die after feeding on heavily infected blood meals.
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further observations on in vitro hybridization of hemosporidian parasites patterns of ookinete development in haemoproteus spp
Journal of Parasitology, 2013Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Rasa Bernotienė, Asta Križanauskienė, Rita Kazlauskienė, Tatjana A. IezhovaAbstract:Abstract: Increasingly frequent outbreaks of zoonotic infections call for studies of wildlife parasites to reach a better understanding of the mechanisms of host switch, leading to the evolution of new diseases. However, speciation processes have been insufficiently addressed in experimental parasitology studies, primarily due to difficulties in determining and measuring mate-recognition signals in parasites. We investigated patterns of sexual process and ookinete development in avian Haemoproteus (Parahaemoproteus) spp. (Haemosporida, Haemoproteidae) using in vitro experiments on between-lineage hybridization. Eleven mitochondrial cytochrome b (cyt b) lineages belonging to 9 species of hemoproteid were isolated from naturally infected passerine birds. The parasites were identified to species on the basis of morphology of their gametocytes and polymerase chain reaction amplification of segments of the cyt b gene. Sexual process and ookinete development were initiated in vitro by mixing blood containing m...
Matthew C I Medeiros - One of the best experts on this subject based on the ideXlab platform.
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Vector-Borne Blood Parasites of the Great-Tailed Grackle ( Quiscalus mexicanus) in East-Central Texas, USA
Microorganisms, 2021Co-Authors: Andrew J. Golnar, Matthew C I Medeiros, Sarah A. Hamer, Katlyn Rosenbaum, Justin R Bejcek, Gabriel L. HamerAbstract:Great-tailed grackles (Quiscalus mexicanus) have dramatically expanded into North America over the past century. However, little is known about the blood that parasites they support. Here, for the first time, we document an assemblage of trypanosome, Haemosporida, and filarial nematodes co-circulating in invasive great-tailed grackles. Between February and July, 2015, 61 individuals were captured in an urban environment of College Station, Texas. Field microscopy and molecular diagnostics indicate that 52% (24/46) were visually infected with filarioid nematodes, 24% (11/46) with avian trypanosomes, and 73% (n = 44/60) with Haemosporida parasites, such as Haemoproteus (Parahaemoproteus) and Plasmodium cathemerium. Overall, 87% of great-tailed grackles were infected with blood parasites. Although 50% of individuals hosted parasites from multiple phylum, no patterns of parasite assembly were observed. Results indicate that great-tailed grackles can support a relatively high level of blood parasitism. However, the consequences for avian health remain to be determined.
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a novel Haemosporida clade at the rank of genus in north american cranes aves gruiformes
Molecular Phylogenetics and Evolution, 2017Co-Authors: Miranda R Bertram, Karen F Snowden, Matthew C I Medeiros, Diana C Outlaw, Barry K. Hartup, Sarah A. Hamer, Gabriel L. HamerAbstract:The unicellular blood parasites in the order Haemosporida are highly diverse, infect many vertebrates, are responsible for a large disease burden among humans and animals, and have reemerged as an important model system to understand the evolutionary and ecological dynamics of host-parasite interactions. The phylogenetics and systematics of Haemosporida are limited by poor sampling of different vertebrate host taxa. We surveyed the Haemosporida of wild whooping cranes (Grus americana) and sandhill cranes (Grus canadensis) (Aves: Gruiformes) using a combination of morphological and molecular approaches. We identified Haemoproteus antigonis in blood smears based on published morphological descriptions. Phylogenetic analysis based on partial cytochrome b (cytb) and cytochrome oxidase (coI) sequences placed H. antigonis parasites in a novel clade, distinct from all avian Haemosporida genera for which cytb and/or coI sequences are available. Molecular clock and divergence estimates suggest this crane clade may represent a new genus. This is the first molecular description of H. antigonis and the first report of H. antigonis in wild whooping cranes, an endangered bird in North America. Further sampling of Haemosporida, especially from hosts of the Gruiformes and other poorly sampled orders, will help to resolve the relationship of the H. antigonis clade to other avian Haemosporida genera. Our study highlights the potential of sampling neglected host species to discover novel lineages of diverse parasite groups.
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Haemosporida prevalence and diversity are similar in endangered wild whooping cranes (Grus americana) and sympatric sandhill cranes (Grus canadensis).
Parasitology, 2016Co-Authors: Miranda R Bertram, Karen F Snowden, Matthew C I Medeiros, Barry K. Hartup, Gabriel L. Hamer, Sarah A. HamerAbstract:The population growth of endangered whooping cranes (Grus americana) is not consistent with species recovery goals, and the impact of parasite infection on whooping crane populations is largely unknown. Disease ecology and epidemiology research of endangered species is often hindered by limited ability to conduct invasive sampling on the target taxa. Accordingly, we hypothesized that sandhill cranes (Grus canadensis) would be a useful surrogate species to investigate the health impacts of Haemosporida infection in whooping cranes. Our goal was to compare the prevalence and diversity of Haemosporida infection between whooping cranes and sandhill cranes. We detected an overall infection prevalence of 83·6% (n = 61) in whooping cranes and 59·6% (n = 47) and 63·6 (n = 22) in two sympatric sandhill crane populations captured in Texas. Prevalence was significantly lower in allopatric sandhill cranes captured in New Mexico (12·1%, n = 33). Haemoproteus antigonis was the most abundant haemoparasite in cranes, present in 57·4% of whooping cranes and 39·2% of sandhill cranes; Plasmodium and Leucocytozoon were present at significantly lower levels. The high prevalence of Haemosporida in whooping cranes and sympatric sandhill cranes, with shared parasite lineages between the two species, supports sandhill cranes as a surrogate species for understanding health threats to endangered whooping cranes.
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Overlap in the Seasonal Infection Patterns of Avian Malaria Parasites and West Nile Virus in Vectors and Hosts.
The American journal of tropical medicine and hygiene, 2016Co-Authors: Matthew C I Medeiros, Robert E Ricklefs, Jeffrey D. Brawn, Marilyn O. Ruiz, Tony L. Goldberg, Gabriel L. HamerAbstract:Abstract Multiple vector-borne pathogens often circulate in the same vector and host communities, and seasonal infection dynamics influence the potential for pathogen interactions. Here, we explore the seasonal infection patterns of avian malaria (Haemosporida) parasites (Plasmodium and Haemoproteus) and West Nile virus (WNV) in birds and mosquitoes in suburban Chicago. We show that both pathogens vary seasonally in Culex mosquitoes and avian hosts, but that patterns of covariation are complex. Different putative Plasmodium species varied asynchronously across the season in mosquitoes and birds, suggesting that different forces may govern their transmission. Infections of Culex mosquitoes with Plasmodium parasites were positively associated with WNV infections in pools of individuals aggregated from the same time and site, suggesting that these pathogens respond to common environmental drivers and co-circulate among the same host and vector populations. Future research should focus on these common drivers, and whether these pathogens interact in vectors and hosts.
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Specialized avian Haemosporida trade reduced host breadth for increased prevalence.
Journal of evolutionary biology, 2014Co-Authors: Matthew C I Medeiros, Vincenzo A. Ellis, Robert E RicklefsAbstract:Parasite specialization on one or a few host species leads to a reduction in the total number of available host individuals, which may decrease transmission. However, specialists are thought to be able to compensate by increased prevalence in the host population and increased success in each individual host. Here, we use variation in host breadth among a community of avian Haemosporida to investigate consequences of generalist and specialist strategies on prevalence across hosts. We show that specialist parasites are more prevalent than generalist parasites in host populations that are shared between them. Moreover, the total number of infections of generalist and specialist parasites within the study area did not vary significantly with host breadth. This suggests that specialists can infect a similar number of host individuals as generalists, thus compensating for a reduction in host availability by achieving higher prevalence in a single host species. Specialist parasites also tended to infect older hosts, whereas infections by generalists were biased towards younger hosts. We suggest that this reflects different abilities of generalists and specialists to persist in hosts following infection. Higher abundance and increased persistence in hosts suggest that specialists are more effective parasites than generalists, supporting the existence of a trade-off between host breadth and average host use among these parasites.
Ravinder N. M. Sehgal - One of the best experts on this subject based on the ideXlab platform.
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A fatal case of a captive snowy owl (Bubo scandiacus) with Haemoproteus infection in Japan.
Parasitology research, 2020Co-Authors: Megumu Yoshimoto, Kenichi Ozawa, Hirotaka Kondo, Yusuke Echigoya, Hisashi Shibuya, Yukita Sato, Ravinder N. M. SehgalAbstract:Parasites of the genus Haemoproteus are vector-borne avian haemosporidia commonly found in bird species of the world. Haemoproteus infections are typically considered relatively benign in birds. However, some Haemoproteus species cause severe disease and mortality, especially for captive birds removed from their original habitat. In September 2018, a captive 15-year-old snowy owl (Bubo scandiacus), kept in a zoological garden of Japan, died subacutely after presenting leg dysfunction. This case showed significantly low PCV and elevated AST, ALT, CK, and LDH values. Many megalomeronts with prominent morphological characteristics of Haemoproteus were observed in the left leg muscles. Those megalomeronts exhibited multilocular structures and were internally filled with merozoites. A new lineage of Haemoproteus was detected by subsequent PCR for the cytochrome b (cytb) gene of avian haemosporidia from DNA extracted from several organ tissues. The detected lineage was classified in the subgenus Parahaemoproteus and was similar to those from the wild birds inhabiting the region including the study area, suggesting that this snowy owl likely acquired its infection from wild birds. This is the first report of a fatal case of a captive bird with a locally transmitted Haemoproteus infection in Japan. We considered the pathogenicity of this infection in conjunction with the clinical course and hematology results. We surmise that snowy owls may be particularly susceptible to infection with Haemoproteus parasites, and warming northern temperatures may exacerbate the overall health of these and other high latitude birds. Further research into the prevalence of Haemoproteus in wild birds near zoological gardens and potential biting midge vectors is necessary for the ex situ conservation of introduced birds.
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Detection and prevalence of Haemoproteus archilochus (Haemosporida, Haemoproteidae) in two species of California hummingbirds
Parasitology research, 2017Co-Authors: A. C. Bradshaw, Jenny S. Carlson, Lisa A. Tell, Holly B. Ernest, S. Bahan, Ravinder N. M. SehgalAbstract:Haemosporidian blood parasites are transmitted to a wide range of avian hosts via blood-sucking dipteran vectors. Microscopy has revealed an impressive diversity of avian haemosporidia with more than 250 species described. Moreover, PCR and subsequent sequence analyses have suggested a much greater diversity of haemosporidia than morphological analyses alone. Given the importance of these parasites, very few studies have focused on the charismatic hummingbirds. To date, three Haemoproteus species (Haemoproteus archilochus, Haemoproteus trochili, and Haemoproteus witti) and one Leucocytozoon species (Leucocytozoon quynzae) have been described in blood samples taken from hummingbirds (Trochilidae). Unconfirmed Plasmodium lineages have also been detected in hummingbirds. Here, we report the detection of H. archilochus in two hummingbird species (Calypte anna and Archilochus alexandri) sampled in Northern California and perform a phylogenetic analysis of mitochondrial cytochrome b (cyt b) gene lineages. A total of 261 hummingbirds (157 C. anna, 104 A. alexandri) were sampled and screened for blood parasites using PCR and microscopy techniques. Combining both methods, 4 (2.55%) haemosporidian infections were detected in C. anna and 18 (17.31%) haemosporidian infections were detected in A. alexandri. Molecular analyses revealed four distinct H. archilocus cyt b lineages, which clustered as a monophyletic clade. No species of Plasmodium or Leucocytozoon were detected in this study, raising the possibility of specific vector associations with hummingbirds. These results provide resources for future studies of haemosporidian prevalence, diversity, and pathogenicity in California hummingbird populations.
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TERMS
2016Co-Authors: Asta Križanauskienė, Tatjana A. Iezhova, Ravinder N. M. Sehgal, Jenny S. CarlsonAbstract:http://zoobank.org/urn:lsid:zoobank.org:pub:185632F5-8CA8-4BFF-B9F0-401DF00EF0AF Molecular characterization of Haemoproteus sacharovi (Haemosporida, Haemoproteidae), a common parasite of columbiform birds, with remarks on classification of haemoproteids of doves and pigeon
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TWO NEW HAEMOPROTEUS SPECIES (Haemosporida: HAEMOPROTEIDAE) FROM COLUMBIFORM BIRDS
The Journal of parasitology, 2012Co-Authors: Gediminas Valkiūnas, Tatjana A. Iezhova, Juan E. Martínez-gómez, Edward L. Evans, Jenny S. Carlson, Ravinder N. M. SehgalAbstract:Here we describe Haemoproteus (Haemoproteus) multivolutinus n. sp. from a tambourine dove (Turtur timpanistria )o f Uganda and Haemoproteus (Haemoproteus) paramultipigmentatus n. sp. (Haemosporida, Haemoproteidae) from the Socorro common ground dove (Columbina passerina socorroensis) of Socorro Island, Mexico. These parasites are described based on the morphology of their blood stages and segments of the mitochondrial cytochrome b gene that can be used for molecular identification and diagnosis of these species. Gametocytes of H. multivolutinus possess rod-like pigment granules and are evenly packed with volutin, which masks pigment granules and darkly stains both macro- and microgametocytes in the early stages of their development. Based on these 2 characters, H. multivolutinus can be readily distinguished from other species of hemoproteids parasitizing columbiform (Columbiformes) birds. Haemoproteus paramultipigmentatus resembles Haemoproteus multipigmentatus; it can be distinguished from the latter parasite primarily due to the broadly ovoid shape of its young gametocytes and significantly fewer pigment granules in its fully developed gametocytes. We provide illustrations of blood stages of the new species, and phylogenetic analyses identify DNA lineages closely related to these parasites. Cytochrome b lineages of Haemoproteus multivolutinus and H. paramultipigmentatus cluster with hippoboscid-transmitted lineages of hemoproteids; thus these parasites likely belong to the subgenus Haemoproteus .W e emphasize the importance of using cytochrome b sequences in conjunction with thorough microscopic descriptions to facilitate future identification of these and other avian hemosporidian species.
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New Avian Haemoproteus Species (Haemosporida: Haemoproteidae) From African Birds, with a Critique of the Use of Host Taxonomic Information in Hemoproteid Classification
The Journal of parasitology, 2011Co-Authors: Tatjana A. Iezhova, Ravinder N. M. Sehgal, Molly Dodge, Thomas B. Smith, Gediminas ValkiūnasAbstract:abstract: Haemoproteus (Parahaemoproteus) micronuclearis n. sp., Haemoproteus (Parahaemoproteus) nucleofascialis n. sp., Haemoproteus (Parahaemoproteus) paranucleophilus n. sp., and Haemoproteus (Parahaemoproteus) homobelopolskyi n. sp. (Haemosporida, Haemoproteidae) are described from African passeriform birds based on the morphology of their blood stages and segments of the mitochondrial cytochrome b gene. Red-billed quelea (Quelea quelea), red-headed malimbe (Malimbus rubricollis), and black-headed weaver (Ploceus melanocephalus) are the type vertebrate hosts of new hemoproteids. It is probable that new species have wide distribution in weavers in sub-Saharan Africa. Both H. micronuclearis and H. nucleofascialis can be readily distinguished from other avian hemoproteids by tiny, compact microgametocyte nuclei that are significantly smaller than macrogametocyte nuclei and are a rare character of hemosporidian parasites. Gametocytes of H. paranucleophilus are closely appressed to the erythrocyte nuclei ...
Robert E Ricklefs - One of the best experts on this subject based on the ideXlab platform.
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Overlap in the Seasonal Infection Patterns of Avian Malaria Parasites and West Nile Virus in Vectors and Hosts.
The American journal of tropical medicine and hygiene, 2016Co-Authors: Matthew C I Medeiros, Robert E Ricklefs, Jeffrey D. Brawn, Marilyn O. Ruiz, Tony L. Goldberg, Gabriel L. HamerAbstract:Abstract Multiple vector-borne pathogens often circulate in the same vector and host communities, and seasonal infection dynamics influence the potential for pathogen interactions. Here, we explore the seasonal infection patterns of avian malaria (Haemosporida) parasites (Plasmodium and Haemoproteus) and West Nile virus (WNV) in birds and mosquitoes in suburban Chicago. We show that both pathogens vary seasonally in Culex mosquitoes and avian hosts, but that patterns of covariation are complex. Different putative Plasmodium species varied asynchronously across the season in mosquitoes and birds, suggesting that different forces may govern their transmission. Infections of Culex mosquitoes with Plasmodium parasites were positively associated with WNV infections in pools of individuals aggregated from the same time and site, suggesting that these pathogens respond to common environmental drivers and co-circulate among the same host and vector populations. Future research should focus on these common drivers, and whether these pathogens interact in vectors and hosts.
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Low prevalence of haemosporidian parasites in shorebirds.
Ardea, 2016Co-Authors: Leticia Soares, Graciela Escudero, Victor A.s. Penha, Robert E RicklefsAbstract:Although shorebirds (Charadriiformes: suborders Scolopaci and Charadrii) face physiological stress during migration and experience a wide range of vector-suitable habitats across their distributions, haemosporidian parasites (order Haemosporida) have rarely been detected in these species worldwide. We ask whether shorebirds remain infection-free when wintering in areas where parasite transmission occurs among landbird species. Blood samples were collected at three locations in Argentina: Patagonia, with an avian assemblage dominated by shorebird species; Mar Chiquita Lagoon, a high-salinity water basin where shorebird and landbird species co-occur; and inland sites in Chaco and Cordoba provinces, where host assemblages included mostly landbird species. We screened 650 samples for the presence of haemosporidian infections and sequenced a part of the parasite mitochondrial cytochrome b gene to determine parasite lineages. Of 342 landbirds, 91 were infected with haemosporidian parasites, compared to only thr...
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Specialized avian Haemosporida trade reduced host breadth for increased prevalence.
Journal of evolutionary biology, 2014Co-Authors: Matthew C I Medeiros, Vincenzo A. Ellis, Robert E RicklefsAbstract:Parasite specialization on one or a few host species leads to a reduction in the total number of available host individuals, which may decrease transmission. However, specialists are thought to be able to compensate by increased prevalence in the host population and increased success in each individual host. Here, we use variation in host breadth among a community of avian Haemosporida to investigate consequences of generalist and specialist strategies on prevalence across hosts. We show that specialist parasites are more prevalent than generalist parasites in host populations that are shared between them. Moreover, the total number of infections of generalist and specialist parasites within the study area did not vary significantly with host breadth. This suggests that specialists can infect a similar number of host individuals as generalists, thus compensating for a reduction in host availability by achieving higher prevalence in a single host species. Specialist parasites also tended to infect older hosts, whereas infections by generalists were biased towards younger hosts. We suggest that this reflects different abilities of generalists and specialists to persist in hosts following infection. Higher abundance and increased persistence in hosts suggest that specialists are more effective parasites than generalists, supporting the existence of a trade-off between host breadth and average host use among these parasites.
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Species formation by host shifting in avian malaria parasites
Proceedings of the National Academy of Sciences of the United States of America, 2014Co-Authors: Robert E Ricklefs, Matthew C I Medeiros, Diana C Outlaw, Vincenzo A. Ellis, Maria Svensson-coelho, Steven C. LattaAbstract:The malaria parasites (Apicomplexa: Haemosporida) of birds are believed to have diversified across the avian host phylogeny well after the origin of most major host lineages. Although many symbionts with direct transmission codiversify with their hosts, mechanisms of species formation in vector-borne parasites, including the role of host shifting, are poorly understood. Here, we examine the hosts of sister lineages in a phylogeny of 181 putative species of malaria parasites of New World terrestrial birds to determine the role of shifts between host taxa in the formation of new parasite species. We find that host shifting, often across host genera and families, is the rule. Sympatric speciation by host shifting would require local reproductive isolation as a prerequisite to divergent selection, but this mechanism is not supported by the generalized host-biting behavior of most vectors of avian malaria parasites. Instead, the geographic distribution of individual parasite lineages in diverse hosts suggests that species formation is predominantly allopatric and involves host expansion followed by local host–pathogen coevolution and secondary sympatry, resulting in local shifting of parasite lineages across hosts.
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Species limits in avian malaria parasites (Haemosporida): how to move forward in the molecular era
Parasitology, 2014Co-Authors: Diana C Outlaw, Robert E RicklefsAbstract:Delimiting species of malaria parasites (Haemosporida) has become increasingly problematic as new lineages of parasites are identified solely by molecular information, particularly mitochondrial cytochrome b sequence data. In this review, we highlight some of the issues, both historical and contemporary, that have hindered the development of objective criteria to diagnose, delimit and define species of haemosporidians. Defining species is not the focal interest of most researchers, most of whom merely wish to determine whether lineages identified in their samples match those of other researchers, and if so, where and in which host species. Rather than revisiting all the issues with respect to delimiting and naming species, we instead focus on finding a practical near-term resolution to the ‘species problem’ that utilizes the community's largest resource: mitochondrial cytochrome b DNA sequences. We recommend a standardized procedure to ‘tag’ these sequences, based on per cent sequence similarity, that will allow researchers to directly assess the novelty, known hosts and geographic distribution of avian malaria parasite lineages.
