Sporogony

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 2148 Experts worldwide ranked by ideXlab platform

Vaidas Palinauskas - One of the best experts on this subject based on the ideXlab platform.

  • Complete Sporogony of the blood parasite Haemoproteus nucleocondensus in common biting midges: why is its transmission interrupted in Europe?
    Parasitology, 2020
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Elena Platonova, Vaidas Palinauskas
    Abstract:

    Haemoproteus species (Haemoproteidae) are widespread blood parasites and are transmitted by Culicoides biting midges and Hippoboscidae louse flies. Although these pathogens may cause morbidity or mortality, the vectors and patterns of transmission remain unknown for the great majority of avian haemoproteids. Haemoproteus nucleocondensus has been frequently reported in Europe in great reed warblers Acrocephalus arundinaceus after their arrival from African wintering grounds, but this infection has not been found in juveniles at the breeding sites. The factors that prevent its transmission remain unclear. This study was designed to test whether the Sporogony of H. nucleocondensus (lineage hGRW8) can be completed in Culicoides impunctatus, one of the most abundant European biting midge species. Wild-caught females were infected with H. nucleocondensus from great reed warblers. Microscopic examination and PCR-based methods were used to detect sporogonic stages and to confirm species identity. This study showed that H. nucleocondensus completes Sporogony in C. impunctatus, suggesting that there are no obstacles to its transmission from the point of view of vector availability and average temperature in Northern Europe. We discuss other ecological factors which should be considered to explain why the transmission of H. nucleocondensus and some other Southern origin haemosporidians are interrupted in North Europe.

  • The widespread biting midge Culicoides impunctatus (Ceratopogonidae) is susceptible to infection with numerous Haemoproteus (Haemoproteidae) species.
    Parasites & Vectors, 2017
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Tatjana A. Iezhova, Mikhail Markovets, Andrey Mukhin, Vaidas Palinauskas
    Abstract:

    Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. All investigated parasites completed Sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the Sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete Sporogony in C. impunctatus. Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during Sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels.

  • The widespread biting midge Culicoides impunctatus (Ceratopogonidae) is susceptible to infection with numerous Haemoproteus (Haemoproteidae) species
    BMC, 2017
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Tatjana A. Iezhova, Mikhail Markovets, Andrey Mukhin, Vaidas Palinauskas
    Abstract:

    Abstract Background Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. Methods Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. Results All investigated parasites completed Sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the Sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete Sporogony in C. impunctatus. Conclusions Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during Sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels

  • Complete Sporogony of Plasmodium relictum (lineage pGRW4) in mosquitoes Culex pipiens pipiens, with implications on avian malaria epidemiology.
    Parasitology Research, 2015
    Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Mikas Ilgūnas, Rasa Bernotienė, Rita Žiegytė, Dovilė Bukauskaitė, Dimitar Dimitrov, Tatjana A. Iezhova
    Abstract:

    Plasmodium relictum (lineage pGRW4) causes malaria in birds and is actively transmitted in countries with warm climates and also temperate regions of the New World. In Europe, the lineage pGRW4 has been frequently reported in many species of Afrotropical migrants after their arrival from wintering grounds, but is rare in European resident birds. Obstacles for transmission of this parasite in Europe have not been identified. Culex quinquefasciatus is an effective vector of pGRW4 malaria, but this mosquito is absent from temperate regions of Eurasia. It remains unclear if the lineage pGRW4 completes Sporogony in European species of mosquitoes. Here we compare the sporogonic development of P. relictum (pGRW4) in experimentally infected mosquitoes Culex pipiens pipiens form molestus, C. quinquefasciatus, and Ochlerotatus cantans. The pGRW4 parasite was isolated from a garden warbler Sylvia borin, multiplied, and used to infect laboratory-reared Culex spp. and wild-caught Ochlerotatus mosquitoes by allowing them to take blood meals on infected birds. The exposed females were maintained at a mean laboratory temperature of 19 °C, which ranged between 14 °C at night and 24 °C during daytime. They were dissected on intervals to study the development of sporogonic stages. Only ookinetes developed in O. cantans; sporogonic development was abortive. The parasite completed Sporogony in both Culex species, with similar patterns of development, and sporozoites were reported in the salivary glands 16 days after infection. The presence of sporogonic stages of the lineage pGRW4 in mosquitoes was confirmed by PCR-based testing of (1) the sporozoites present in salivary glands and (2) the single oocysts, which were obtained by laser microdissection from infected mosquito midguts. This study shows that P. relictum (pGRW4) completes Sporogony in C. p. pipiens at relatively low temperatures. We conclude that there are no restrictions for spreading this bird infection in Europe from the point of view of vector availability and temperature necessary for Sporogony. Other factors should be considered and were discussed for the explanation of rare reports of this malaria parasite in Europe.

  • In vitro development of Haemoproteus parasites: the efficiency of reproductive cells increase during simultaneous sexual process of different lineages.
    Parasitology Research, 2014
    Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Mikas Ilgūnas, Rasa Bernotienė, Tatjana A. Iezhova
    Abstract:

    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.

Gediminas Valkiūnas - One of the best experts on this subject based on the ideXlab platform.

  • Complete Sporogony of the blood parasite Haemoproteus nucleocondensus in common biting midges: why is its transmission interrupted in Europe?
    Parasitology, 2020
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Elena Platonova, Vaidas Palinauskas
    Abstract:

    Haemoproteus species (Haemoproteidae) are widespread blood parasites and are transmitted by Culicoides biting midges and Hippoboscidae louse flies. Although these pathogens may cause morbidity or mortality, the vectors and patterns of transmission remain unknown for the great majority of avian haemoproteids. Haemoproteus nucleocondensus has been frequently reported in Europe in great reed warblers Acrocephalus arundinaceus after their arrival from African wintering grounds, but this infection has not been found in juveniles at the breeding sites. The factors that prevent its transmission remain unclear. This study was designed to test whether the Sporogony of H. nucleocondensus (lineage hGRW8) can be completed in Culicoides impunctatus, one of the most abundant European biting midge species. Wild-caught females were infected with H. nucleocondensus from great reed warblers. Microscopic examination and PCR-based methods were used to detect sporogonic stages and to confirm species identity. This study showed that H. nucleocondensus completes Sporogony in C. impunctatus, suggesting that there are no obstacles to its transmission from the point of view of vector availability and average temperature in Northern Europe. We discuss other ecological factors which should be considered to explain why the transmission of H. nucleocondensus and some other Southern origin haemosporidians are interrupted in North Europe.

  • A new methodology for Sporogony research of avian haemoproteids in laboratory-reared Culicoides spp., with a description of the complete sporogonic development of Haemoproteus pastoris.
    Parasites & Vectors, 2019
    Co-Authors: Dovilė Bukauskaitė, Mikas Ilgūnas, Rasa Bernotienė, Tatjana A. Iezhova, Rita Žiegytė, Carolina Romeiro Fernandes Chagas, Gediminas Valkiūnas
    Abstract:

    BACKGROUND: Haemosporidian parasites of the genus Haemoproteus (Haemoproteidae) are widespread and cause haemoproteosis in birds and therefore, their diversity, ecology and evolutionary biology have become subjects of intensive research. However, the vectors and transmission patterns of haemoproteids as well as the epidemiology of haemoproteosis remain insufficiently investigated. Several species of Culicoides (Ceratopogonidae) support complete Sporogony of haemoproteids belonging to the subgenus Parahaemoproteus. However, experimental research with these fragile insects is difficult to design in the field, particularly because their abundance markedly depends on seasonality. This is an obstacle for continuous sampling of sufficient numbers of naturally infected or experimentally exposed midges from wildlife. We developed simple methodology for accessing sporogonic development of haemoproteids in laboratory-reared Culicoides nubeculosus. This study aimed to describe the mosaic of methods constituting this methodology, which was applied for investigation of the sporogonic development of Haemoproteus (Parahaemoproteus) pastoris, a widespread parasite of the common starling Sturnus vulgaris. METHODS: The methodology consists of the following main stages: (i) laboratory rearing of C. nubeculosus from the egg stage to adult insects; (ii) selection of naturally infected birds, the donors of mature gametocytes to expose biting midges; (iii) experimental exposure of insects and their laboratory maintenance; and (iv) dissection of exposed insects. Biting midges were exposed to H. pastoris (cytochrome b lineage hLAMPUR01) detected in one naturally infected common starling. Engorged insects were dissected at intervals in order to follow Sporogony. Microscopic examination and PCR-based methods were used to identify the sporogonic stages and to confirm the presence of the parasite lineage in infected insects, respectively. RESULTS: Culicoides nubeculosus females were successfully reared and exposed to H. pastoris, which completed sporogonic development 7–9 days post-infection when sporozoites were observed in the salivary glands. CONCLUSIONS: The new methodology is easy to use and non-harmful for birds, providing opportunities to access the sporogonic stages of Parahaemoproteus parasites, which might be used in a broad range of parasitology and genetic studies. Culicoides nubeculosus is an excellent experimental vector of subgenus Parahaemoproteus and is recommended for various experimental studies aiming investigation of Sporogony of these pathogens.

  • The widespread biting midge Culicoides impunctatus (Ceratopogonidae) is susceptible to infection with numerous Haemoproteus (Haemoproteidae) species.
    Parasites & Vectors, 2017
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Tatjana A. Iezhova, Mikhail Markovets, Andrey Mukhin, Vaidas Palinauskas
    Abstract:

    Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. All investigated parasites completed Sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the Sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete Sporogony in C. impunctatus. Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during Sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels.

  • The widespread biting midge Culicoides impunctatus (Ceratopogonidae) is susceptible to infection with numerous Haemoproteus (Haemoproteidae) species
    BMC, 2017
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Tatjana A. Iezhova, Mikhail Markovets, Andrey Mukhin, Vaidas Palinauskas
    Abstract:

    Abstract Background Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. Methods Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. Results All investigated parasites completed Sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the Sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete Sporogony in C. impunctatus. Conclusions Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during Sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels

  • Complete Sporogony of Plasmodium relictum (lineage pGRW4) in mosquitoes Culex pipiens pipiens, with implications on avian malaria epidemiology.
    Parasitology Research, 2015
    Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Mikas Ilgūnas, Rasa Bernotienė, Rita Žiegytė, Dovilė Bukauskaitė, Dimitar Dimitrov, Tatjana A. Iezhova
    Abstract:

    Plasmodium relictum (lineage pGRW4) causes malaria in birds and is actively transmitted in countries with warm climates and also temperate regions of the New World. In Europe, the lineage pGRW4 has been frequently reported in many species of Afrotropical migrants after their arrival from wintering grounds, but is rare in European resident birds. Obstacles for transmission of this parasite in Europe have not been identified. Culex quinquefasciatus is an effective vector of pGRW4 malaria, but this mosquito is absent from temperate regions of Eurasia. It remains unclear if the lineage pGRW4 completes Sporogony in European species of mosquitoes. Here we compare the sporogonic development of P. relictum (pGRW4) in experimentally infected mosquitoes Culex pipiens pipiens form molestus, C. quinquefasciatus, and Ochlerotatus cantans. The pGRW4 parasite was isolated from a garden warbler Sylvia borin, multiplied, and used to infect laboratory-reared Culex spp. and wild-caught Ochlerotatus mosquitoes by allowing them to take blood meals on infected birds. The exposed females were maintained at a mean laboratory temperature of 19 °C, which ranged between 14 °C at night and 24 °C during daytime. They were dissected on intervals to study the development of sporogonic stages. Only ookinetes developed in O. cantans; sporogonic development was abortive. The parasite completed Sporogony in both Culex species, with similar patterns of development, and sporozoites were reported in the salivary glands 16 days after infection. The presence of sporogonic stages of the lineage pGRW4 in mosquitoes was confirmed by PCR-based testing of (1) the sporozoites present in salivary glands and (2) the single oocysts, which were obtained by laser microdissection from infected mosquito midguts. This study shows that P. relictum (pGRW4) completes Sporogony in C. p. pipiens at relatively low temperatures. We conclude that there are no restrictions for spreading this bird infection in Europe from the point of view of vector availability and temperature necessary for Sporogony. Other factors should be considered and were discussed for the explanation of rare reports of this malaria parasite in Europe.

Ian R Menz - One of the best experts on this subject based on the ideXlab platform.

M. Sonoda - One of the best experts on this subject based on the ideXlab platform.

  • Sporogony of Theileria sergenti in the salivary glands of the tick vector Haemaphysalis longicornis.
    Parasitology Research, 1993
    Co-Authors: K. Takahashi, Satoru Kawai, K. Yaehata, Satoshi Kawamoto, Katsuro Hagiwara, Takashi Kurosawa, Motoshi Tajima, M. Sonoda
    Abstract:

    Sporogony ofTheileria sergenti in the salivary glands of the tick vectorHaemaphysalis longicornis was observed by light and transmission electron microscopy. Fission bodies that developed from kinetes were observed as masses (approximately 32×15 μm) that occupied half of the acinous cell at 2 days after the infestation of ticks. Parasites possessed an irregular nucleus of low electron density, highly electron-dense granules, and mitochondrion-like bodies in the cytoplasm. Parasites developed into a multinucleate syncytium, increasing in size and complexity. Subsequently, the nuclei of parasites became round and highly electron-dense, and tubelike structures and rhoptries as precursors of the highly electron-dense granules appeared in the cytoplasm. Approximately 40,000 sporozoites arose via radial budding from the syncytium that had developed from kinetes. As inT. parva, no evidence of discrete secondary or tertiary sporoblasts was found inT. sergenti. The Sporogony ofT. sergenti was extremely similar to that ofT. parva.

  • Sporogony ofTheileria sergenti in the salivary glands of the tick vectorHaemaphysalis longicornis
    Parasitology Research, 1993
    Co-Authors: K. Takahashi, Satoru Kawai, K. Yaehata, Satoshi Kawamoto, Katsuro Hagiwara, Takashi Kurosawa, Motoshi Tajima, M. Sonoda
    Abstract:

    Sporogony of Theileria sergenti in the salivary glands of the tick vector Haemaphysalis longicornis was observed by light and transmission electron microscopy. Fission bodies that developed from kinetes were observed as masses (approximately 32×15 μm) that occupied half of the acinous cell at 2 days after the infestation of ticks. Parasites possessed an irregular nucleus of low electron density, highly electron-dense granules, and mitochondrion-like bodies in the cytoplasm. Parasites developed into a multinucleate syncytium, increasing in size and complexity. Subsequently, the nuclei of parasites became round and highly electron-dense, and tubelike structures and rhoptries as precursors of the highly electron-dense granules appeared in the cytoplasm. Approximately 40,000 sporozoites arose via radial budding from the syncytium that had developed from kinetes. As in T. parva , no evidence of discrete secondary or tertiary sporoblasts was found in T. sergenti . The Sporogony of T. sergenti was extremely similar to that of T. parva .

Rita Žiegytė - One of the best experts on this subject based on the ideXlab platform.

  • Complete Sporogony of the blood parasite Haemoproteus nucleocondensus in common biting midges: why is its transmission interrupted in Europe?
    Parasitology, 2020
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Elena Platonova, Vaidas Palinauskas
    Abstract:

    Haemoproteus species (Haemoproteidae) are widespread blood parasites and are transmitted by Culicoides biting midges and Hippoboscidae louse flies. Although these pathogens may cause morbidity or mortality, the vectors and patterns of transmission remain unknown for the great majority of avian haemoproteids. Haemoproteus nucleocondensus has been frequently reported in Europe in great reed warblers Acrocephalus arundinaceus after their arrival from African wintering grounds, but this infection has not been found in juveniles at the breeding sites. The factors that prevent its transmission remain unclear. This study was designed to test whether the Sporogony of H. nucleocondensus (lineage hGRW8) can be completed in Culicoides impunctatus, one of the most abundant European biting midge species. Wild-caught females were infected with H. nucleocondensus from great reed warblers. Microscopic examination and PCR-based methods were used to detect sporogonic stages and to confirm species identity. This study showed that H. nucleocondensus completes Sporogony in C. impunctatus, suggesting that there are no obstacles to its transmission from the point of view of vector availability and average temperature in Northern Europe. We discuss other ecological factors which should be considered to explain why the transmission of H. nucleocondensus and some other Southern origin haemosporidians are interrupted in North Europe.

  • A new methodology for Sporogony research of avian haemoproteids in laboratory-reared Culicoides spp., with a description of the complete sporogonic development of Haemoproteus pastoris.
    Parasites & Vectors, 2019
    Co-Authors: Dovilė Bukauskaitė, Mikas Ilgūnas, Rasa Bernotienė, Tatjana A. Iezhova, Rita Žiegytė, Carolina Romeiro Fernandes Chagas, Gediminas Valkiūnas
    Abstract:

    BACKGROUND: Haemosporidian parasites of the genus Haemoproteus (Haemoproteidae) are widespread and cause haemoproteosis in birds and therefore, their diversity, ecology and evolutionary biology have become subjects of intensive research. However, the vectors and transmission patterns of haemoproteids as well as the epidemiology of haemoproteosis remain insufficiently investigated. Several species of Culicoides (Ceratopogonidae) support complete Sporogony of haemoproteids belonging to the subgenus Parahaemoproteus. However, experimental research with these fragile insects is difficult to design in the field, particularly because their abundance markedly depends on seasonality. This is an obstacle for continuous sampling of sufficient numbers of naturally infected or experimentally exposed midges from wildlife. We developed simple methodology for accessing sporogonic development of haemoproteids in laboratory-reared Culicoides nubeculosus. This study aimed to describe the mosaic of methods constituting this methodology, which was applied for investigation of the sporogonic development of Haemoproteus (Parahaemoproteus) pastoris, a widespread parasite of the common starling Sturnus vulgaris. METHODS: The methodology consists of the following main stages: (i) laboratory rearing of C. nubeculosus from the egg stage to adult insects; (ii) selection of naturally infected birds, the donors of mature gametocytes to expose biting midges; (iii) experimental exposure of insects and their laboratory maintenance; and (iv) dissection of exposed insects. Biting midges were exposed to H. pastoris (cytochrome b lineage hLAMPUR01) detected in one naturally infected common starling. Engorged insects were dissected at intervals in order to follow Sporogony. Microscopic examination and PCR-based methods were used to identify the sporogonic stages and to confirm the presence of the parasite lineage in infected insects, respectively. RESULTS: Culicoides nubeculosus females were successfully reared and exposed to H. pastoris, which completed sporogonic development 7–9 days post-infection when sporozoites were observed in the salivary glands. CONCLUSIONS: The new methodology is easy to use and non-harmful for birds, providing opportunities to access the sporogonic stages of Parahaemoproteus parasites, which might be used in a broad range of parasitology and genetic studies. Culicoides nubeculosus is an excellent experimental vector of subgenus Parahaemoproteus and is recommended for various experimental studies aiming investigation of Sporogony of these pathogens.

  • The widespread biting midge Culicoides impunctatus (Ceratopogonidae) is susceptible to infection with numerous Haemoproteus (Haemoproteidae) species.
    Parasites & Vectors, 2017
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Tatjana A. Iezhova, Mikhail Markovets, Andrey Mukhin, Vaidas Palinauskas
    Abstract:

    Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. All investigated parasites completed Sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the Sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete Sporogony in C. impunctatus. Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during Sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels.

  • The widespread biting midge Culicoides impunctatus (Ceratopogonidae) is susceptible to infection with numerous Haemoproteus (Haemoproteidae) species
    BMC, 2017
    Co-Authors: Rita Žiegytė, Gediminas Valkiūnas, Rasa Bernotienė, Tatjana A. Iezhova, Mikhail Markovets, Andrey Mukhin, Vaidas Palinauskas
    Abstract:

    Abstract Background Haemoproteus parasites are widespread, and some species cause disease in wild and domestic birds. However, the insect vectors remain unknown for the majority of species and genetic lineages of avian Haemoproteus. This information is crucial for better understanding the biology of haemoproteids, the epidemiology of haemoproteosis, and the development of morphological characters of sporogonic stages in wildlife haemosporidian parasites. It remains unclear whether the specificity of Haemoproteus parasites for vectors is broad or the transmission of a given parasite can be restricted to a single or few species of vectors. The aim of this study was to examine the sporogonic development of four species of common European avian haemoproteids in the common biting midge Culicoides impunctatus. Methods Wild-caught females of C. impunctatus were infected experimentally by allowing them to take blood meals on naturally infected Muscicapa striata, Cyanistes caeruleus, Ficedula hypoleuca and Motacilla flava harbouring mature gametocytes of Haemoproteus balmorali (genetic lineage hSFC9), H. majoris (hPARUS1), H. motacillae (hYWT1) and H. pallidus (hPFC1), respectively. Infected insects were collected, maintained under laboratory conditions and dissected daily in order to detect the development of ookinetes, oocysts and sporozoites. Microscopic examination and polymerase chain reaction based methods were used to detect the parasites. Bayesian analysis was applied to identify phylogenetic relationships among Haemoproteus lineages. Results All investigated parasites completed Sporogony in C. impunctatus, indicating broad susceptibility of this biting midge for numerous Haemoproteus parasites. Ookinetes, oocysts and sporozoites were reported, described and compared morphologically. The investigated parasite species can be distinguished at the Sporogony stage, particularly with regards to the morphology and rate of development of mature ookinetes. Analysis of data from the literature, and this study, shows that 12 genetically distantly related Haemoproteus parasites complete Sporogony in C. impunctatus. Conclusions Susceptibility of C. impunctatus is broad for Haemoproteus parasites, indicating that this biting midge is an important natural vector of numerous species of avian haemoproteids in Europe. Some Haemoproteus species can be readily distinguished using morphological characters of ookinetes and sporozoites, as well as the rate of ookinete development. These characters can be used for the identification of Haemoproteus species during Sporogony in vectors, and are worth more attention in these parasite taxonomy studies at the species levels

  • Complete Sporogony of Plasmodium relictum (lineage pGRW4) in mosquitoes Culex pipiens pipiens, with implications on avian malaria epidemiology.
    Parasitology Research, 2015
    Co-Authors: Gediminas Valkiūnas, Vaidas Palinauskas, Mikas Ilgūnas, Rasa Bernotienė, Rita Žiegytė, Dovilė Bukauskaitė, Dimitar Dimitrov, Tatjana A. Iezhova
    Abstract:

    Plasmodium relictum (lineage pGRW4) causes malaria in birds and is actively transmitted in countries with warm climates and also temperate regions of the New World. In Europe, the lineage pGRW4 has been frequently reported in many species of Afrotropical migrants after their arrival from wintering grounds, but is rare in European resident birds. Obstacles for transmission of this parasite in Europe have not been identified. Culex quinquefasciatus is an effective vector of pGRW4 malaria, but this mosquito is absent from temperate regions of Eurasia. It remains unclear if the lineage pGRW4 completes Sporogony in European species of mosquitoes. Here we compare the sporogonic development of P. relictum (pGRW4) in experimentally infected mosquitoes Culex pipiens pipiens form molestus, C. quinquefasciatus, and Ochlerotatus cantans. The pGRW4 parasite was isolated from a garden warbler Sylvia borin, multiplied, and used to infect laboratory-reared Culex spp. and wild-caught Ochlerotatus mosquitoes by allowing them to take blood meals on infected birds. The exposed females were maintained at a mean laboratory temperature of 19 °C, which ranged between 14 °C at night and 24 °C during daytime. They were dissected on intervals to study the development of sporogonic stages. Only ookinetes developed in O. cantans; sporogonic development was abortive. The parasite completed Sporogony in both Culex species, with similar patterns of development, and sporozoites were reported in the salivary glands 16 days after infection. The presence of sporogonic stages of the lineage pGRW4 in mosquitoes was confirmed by PCR-based testing of (1) the sporozoites present in salivary glands and (2) the single oocysts, which were obtained by laser microdissection from infected mosquito midguts. This study shows that P. relictum (pGRW4) completes Sporogony in C. p. pipiens at relatively low temperatures. We conclude that there are no restrictions for spreading this bird infection in Europe from the point of view of vector availability and temperature necessary for Sporogony. Other factors should be considered and were discussed for the explanation of rare reports of this malaria parasite in Europe.

Sporogony - 15 days free trial to Access Experts & Abstracts