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1.
Parasitol Res ; 119(9): 2975-2981, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32683557

RESUMO

Haemosporidia infections may cause major damage to avian populations and represent a concern for veterinarians working in zoological parks or wildlife rescue centres. Following the fatal infection of 9 Great grey owls (Strix nebulosa) at Mulhouse zoological park, between summer 2013 and 2015, a prospective epidemiological investigation was performed in captive strigiform birds in France in 2016. The purpose was to evaluate the prevalence of haemosporidian parasites in captive Strigiformes and to estimate the infection dynamics around the nesting period. Blood samples were taken from 122 strigiform birds representing 14 species from 15 French zoological parks. Parasites were detected by direct examination of blood smears and by PCR targeting the mitochondrial cytochrome b gene. Haemosporidian parasites were detected in 59 birds from 11 zoos. Three distinct Haemoproteus mitochondrial cytochrome b sequences (haplotypes A and C for H. syrnii and haplotype B for Haemoproteus sp.) as well as two species of Plasmodium were detected. The overall prevalence of Haemoproteus infection was 12.8%. The percentage of birds infected by Haemoproteus varied according to the period of sampling. Nesting season seemed to be at greater risk with an average prevalence of 53.9% compared with winter season with an average prevalence of 14.8%, related to the abundance of the vectors. The prevalence of Plasmodium infection in Strigiformes did not exceed 8% throughout the year. This study confirmed how significant Haemosporidia infection could be in Strigiformes from zoological parks in France. The nesting season was identified as a period of higher risk of infection and consequently the appropriate period to apply prophylactic measures.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Citocromos b/genética , França/epidemiologia , Haemosporida/classificação , Haemosporida/genética , Haplótipos , Filogenia , Estudos Prospectivos , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/epidemiologia , Proteínas de Protozoários/genética
2.
Acta Trop ; 207: 105486, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32330450

RESUMO

Haemoproteus species (Haemosporida, Haemoproteidae) are cosmopolitan bird blood parasites, which often cause relatively benign infections in adapted avian hosts, but severe and even lethal haemoproteosis might develop due to internal organ damage if these pathogens inhabit non-adapted (wrong) hosts. Haemoproteids of swallows (Hirundinidae) remain fragmentarily investigated, with only two haemoproteid species reported in this bird family, which members are cosmopolitan, diverse and inhabit various terrestrial ecosystems, particularly in tropical countries. This study describes and provides molecular characterization of Haemoproteus parahirundinis n. sp. (cytochrome b lineage hHIRUS05), parasite of the most broadly distributed swallow, the Barn swallow Hirundo rustica. Gametocytes, gametes and ookinetes of the new species were examined and compared with other haemoproteids described in swallows. The phylogenetic analysis indicated the existence of a largely undescribed Haemoproteus species diversity in birds of the Hirundinidae and also suggests that all lineages of haemoproteids reported in swallows are transmitted by Culicoides biting midges, but not louse flies of the Hippoboscidae, which often inhabit their nests. The biting midges should be the first targets in vectors research of swallow haemoproteids. This study indicates existence of Haemoproteus species, which are readily distinct based on morphological characters of their blood and sporogonic stages, but differ only negligently in partial cytochrome b sequences, the main markers broadly used in molecular characterization of haemoproteids. That calls for further taxonomic research on haemoproteid in swallows, many species of which are endangered or even threatened with extinction because of habitat degradation.


Assuntos
Haemosporida/genética , Andorinhas/parasitologia , Animais , Doenças das Aves/transmissão , Citocromos b/genética , Haemosporida/classificação , Filogenia , Infecções Protozoárias em Animais/transmissão
3.
Parasitol Res ; 119(5): 1563-1572, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32246260

RESUMO

In temperate regions, some avian haemosporidian parasites have evolved seasonal transmission strategies, with chronic infections relapsing during spring and transmission peaking during the hosts' breeding season. Because lineages with seasonal transmission strategies are unlikely to produce gametocytes in winter, we predicted that (1) resident birds living within wintering areas of Neotropical migrants would unlikely be infected with North American parasite lineages; and (2) if infected, wintering migratory birds would be more likely to harbor Plasmodium spp. rather than Parahaemoproteus spp. or Haemoproteus spp. parasites in their bloodstreams, as only Plasmodium produces life stages, other than gametocytes, that infect red blood cells. To test these predictions, we used molecular detection and microscopy to compare the diversity and prevalence of haemosporidian parasites among year-round residents and wintering migratory birds during February 2016, on three islands of The Bahamas archipelago, i.e., Andros, Grand Bahama, and Great Abaco. Infection prevalence was low and comparable between migratory (15/111) and resident (15/129) individuals, and it did not differ significantly among islands. Out of the 12 lineages detected infecting migratory birds, five were transmitted in North America; four lineages could have been transmitted during breeding, wintering, or migration; and three lineages were likely transmitted in The Bahamas. Resident birds mostly carried lineages endemic to the Caribbean region. All North American-transmitted parasite lineages detected among migratory birds were Plasmodium spp. Our findings suggest that haemosporidian parasites of migrants shift resource allocation seasonally, minimizing the production of gametocytes during winter, with low risk of infection spillover to resident birds.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/isolamento & purificação , Plasmodium/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Migração Animal/fisiologia , Animais , Bahamas/epidemiologia , Doenças das Aves/epidemiologia , Haemosporida/classificação , Haemosporida/genética , Plasmodium/genética , Prevalência , Infecções Protozoárias em Animais/parasitologia , Estações do Ano
4.
J Parasitol ; 106(2): 211-220, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32164026

RESUMO

Biogeography is known to have shaped the diversity and evolutionary history of avian haemosporidian parasites across the Neotropics. However, a paucity of information exists for the temperate Neotropics and especially from nonpasserine hosts. To understand the effect of biogeography in the temperate Neotropics on haemosporidians of nonpasserine hosts we screened ducks (Anseriformes) from central Chile for the presence of these parasites. Forty-two individuals of 4 duck species (Anas flavirostris, Anas georgica, Mareca sibilatrix, Spatula cyanoptera cyanoptera) were collected and assessed for haemosporidian parasite infections by real-time polymerase chain reaction screening and subsequent sequencing of the mitochondrial cytochrome b gene. Haemoproteus (subgenus Haemoproteus) and Plasmodium were detected in 2 host species, A. georgica and S. c. cyanoptera, with no Leucocytozoon found. Overall haemosporidian prevalence was low (14.2%), with the prevalence of Plasmodium (11.9%) being substantially greater than that of Haemoproteus (4.8%). Six haemosporidian cytochrome b lineages were recovered, 2 Haemoproteus and 4 Plasmodium, with all 6 lineages identified for the first time. In phylogenetic reconstruction, the Chilean Plasmodium lineages were more closely related to South American lineages from passerine birds than to known lineages from anseriforms. The subgenus Haemoproteus known from nonpasseriformes has never been identified from any anseriform host; however, we recovered 2 lineages from this subgenus, one from each A. georgica and S. c. cyanoptera. Further work is needed to determine if this presents true parasitism in ducks or only a spillover infection. The results of phylogenetic reconstruction demonstrate a unique evolutionary history of these Chilean parasites, differing from what is known for this host group. The unique geography of Chile, with a large part of the country being relatively isolated by the Atacama Desert in the north and the Andes in the east and south, would present opportunities for parasite diversification. Further work is needed to investigate how strongly the biogeographical isolation has shaped the haemosporidian parasites of this area. Our results add to the growing body of evidence that nonpasserine hosts support unique lineages of haemosporidian parasites, while also demonstrating the role of biogeography in haemosporidian parasite diversity in the temperate Neotropics.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Patos/parasitologia , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Animais , Teorema de Bayes , Evolução Biológica , Distribuição de Qui-Quadrado , Chile/epidemiologia , DNA de Protozoário/análise , DNA de Protozoário/sangue , DNA de Protozoário/isolamento & purificação , Haemosporida/classificação , Haemosporida/genética , Funções Verossimilhança , Fígado/parasitologia , Filogenia , Filogeografia , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/parasitologia
5.
Acta Trop ; 204: 105364, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32007445

RESUMO

Haemosporidian parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus are one of the most prevalent and widely studied groups of parasites infecting birds. Plasmodium is the most well-known haemosporidian as the avian parasite Plasmodium relictum was the original transmission model for human malaria and was also responsible for catastrophic effects on native avifauna when introduced to Hawaii. The past two decades have seen a dramatic increase in research on avian haemosporidian parasites as a model system to understand evolutionary and ecological parasite-host relationships. Despite haemosporidians being one the best studied groups of avian parasites their specialization among avian hosts and variation in prevalence amongst regions and host taxa are not fully understood. In this review we focus on describing the current phylogenetic and morphological diversity of haemosporidian parasites, their specificity among avian and vector hosts, and identifying the determinants of haemosporidian prevalence among avian species. We also discuss how these parasites might spread across regions due to global climate change and the importance of avian migratory behavior in parasite dispersion and subsequent diversification.


Assuntos
Malária Aviária/epidemiologia , Plasmodium/classificação , Animais , Aves/parasitologia , Mudança Climática , Ecologia , Haemosporida/classificação , Hawaii/epidemiologia , Interações Hospedeiro-Parasita , Malária Aviária/parasitologia , Filogenia , Plasmodium/fisiologia , Prevalência
6.
Mol Ecol Resour ; 20(1): 14-28, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31507097

RESUMO

Metatranscriptomics is a powerful method for studying the composition and function of complex microbial communities. The application of metatranscriptomics to multispecies parasite infections is of particular interest, as research on parasite evolution and diversification has been hampered by technical challenges to genome-scale DNA sequencing. In particular, blood parasites of vertebrates are abundant and diverse although they often occur at low infection intensities and exist as multispecies infections, rendering the isolation of genomic sequence data challenging. Here, we use birds and their diverse haemosporidian parasites to illustrate the potential for metatranscriptome sequencing to generate large quantities of genome-wide sequence data from multiple blood parasite species simultaneously. We used RNA-sequencing of 24 blood samples from songbirds in North America to show that metatranscriptomes can yield large proportions of haemosporidian protein-coding gene repertoires even when infections are of low intensity (<0.1% red blood cells infected) and consist of multiple parasite taxa. By bioinformatically separating host and parasite transcripts and assigning them to the haemosporidian genus of origin, we found that transcriptomes detected ~23% more total parasite infections across all samples than were identified using microscopy and DNA barcoding. For single-species infections, we obtained data for >1,300 loci from samples with as low as 0.03% parasitaemia, with the number of loci increasing with infection intensity. In total, we provide data for 1,502 single-copy orthologous loci from a phylogenetically diverse set of 33 haemosporidian mitochondrial lineages. The metatranscriptomic approach described here has the potential to accelerate ecological and evolutionary research on haemosporidians and other diverse parasites.


Assuntos
Doenças das Aves/parasitologia , Sangue/parasitologia , Genômica/métodos , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/sangue , Haemosporida/classificação , Haemosporida/genética , Filogenia , Infecções Protozoárias em Animais/sangue , Aves Canoras/sangue , Aves Canoras/parasitologia , Transcriptoma
7.
Parasitol Res ; 119(2): 601-609, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31754857

RESUMO

The Bellinger River snapping turtle (Myuchelys georgesi) is endemic to Australia and is confined to a highly restricted distribution in the Bellinger River in New South Wales. Routine veterinary health examinations of 17 healthy turtles were undertaken, along with the collection and analysis of blood samples, during conservation efforts to save the species following a catastrophic population decline. Microscopy analysis of blood films detected Haemoproteidae parasites that morphologically resembled Haemocystidium chelodinae inside turtle erythrocytes. Of the 17 turtles examined, 16 were positive for infection with H. chelodinae by both light microscopy and PCR. DNA sequencing of a partial fragment of the mitochondrial cytochrome b (cytb) gene and phylogenetic analysis identified two different H. chelodinae-like genotypes. The phylogenetic relationship of H. chelodinae-like to other Haemoproteidae species based on cytb sequences grouped H. chelodinae-like into the reptile clade, but revealed the Haemocystidium genus to be paraphyletic as the clade also contained Haemoproteus, thus supporting a re-naming of Haemoproteus species from reptiles to Haemocystidium species. This study reports for the first time the genetic characterisation of H. chelodinae-like organisms isolated from a new Testudine host species, the Bellinger River snapping turtle. As evidence grows, further research will be necessary to understand the mode of transmission and to investigate whether these parasites are pathogenic to their hosts.


Assuntos
Haemosporida/isolamento & purificação , Tartarugas/parasitologia , Animais , Austrália , Citocromos b/genética , DNA de Protozoário , Feminino , Genes Mitocondriais , Haemosporida/classificação , Haemosporida/genética , Masculino , New South Wales , Filogenia , Reação em Cadeia da Polimerase , Rios , Análise de Sequência de DNA/veterinária
8.
Parasit Vectors ; 12(1): 516, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685020

RESUMO

BACKGROUND: Haemoproteus parasites (Haemosporida, Haemoproteidae) are cosmopolitan in birds and recent molecular studies indicate enormous genetic diversity of these pathogens, which cause diseases in non-adapted avian hosts. However, life-cycles remain unknown for the majority of Haemoproteus species. Information on their exoerythrocytic development is particularly fragmental and controversial. This study aimed to gain new knowledge on life-cycle of the widespread blood parasite Haemoproteus majoris. METHODS: Turdus pilaris and Parus major naturally infected with lineages hPHYBOR04 and hPARUS1 of H. majoris, respectively, were wild-caught and the parasites were identified using microscopic examination of gametocytes and PCR-based testing. Bayesian phylogeny was used to determine relationships between H. majoris lineages. Exoerythrocytic stages (megalomeronts) were reported using histological examination and laser microdissection was applied to isolate single megalomeronts for genetic analysis. Culicoides impunctatus biting midges were experimentally exposed in order to follow sporogonic development of the lineage hPHYBOR04. RESULTS: Gametocytes of the lineage hPHYBOR04 are indistinguishable from those of the widespread lineage hPARUS1 of H. majoris, indicating that both of these lineages belong to the H. majoris group. Phylogenetic analysis supported this conclusion. Sporogony of the lineage hPHYBOR04 was completed in C. impunctatus biting midges. Morphologically similar megalomeronts were reported in internal organs of both avian hosts. These were big roundish bodies (up to 360 µm in diameter) surrounded by a thick capsule-like wall and containing irregularly shaped cytomeres, in which numerous merozoites developed. DNA sequences obtained from single isolated megalomeronts confirmed the identification of H. majoris. CONCLUSIONS: Phylogenetic analysis identified a group of closely related H. majoris lineages, two of which are characterized not only by morphologically identical blood stages, but also complete sporogonic development in C. impunctatus and development of morphologically similar megalomeronts. It is probable that other lineages belonging to the same group would bear the same characters and phylogenies based on partial cytb gene could be used to predict life-cycle features in avian haemoproteids including vector identity and patterns of exoerythrocytic merogony. This study reports morphologically unique megalomeronts in naturally infected birds and calls for research on exoerythrocytic development of haemoproteids to better understand pathologies caused in avian hosts.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Passeriformes/parasitologia , Infecções Protozoárias em Animais/parasitologia , Aves Canoras/parasitologia , Animais , Teorema de Bayes , Aves , Ceratopogonidae/parasitologia , Haemosporida/classificação , Haemosporida/genética , Filogenia
9.
Parasit Vectors ; 12(1): 422, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462309

RESUMO

BACKGROUND: Haemoproteus (Parahaemoproteus) species (Haemoproteidae) are widespread blood parasites that can cause disease in birds, but information about their vector species, sporogonic development and transmission remain fragmentary. This study aimed to investigate the complete sporogonic development of four Haemoproteus species in Culicoides nubeculosus and to test if phylogenies based on the cytochrome b gene (cytb) reflect patterns of ookinete development in haemosporidian parasites. Additionally, one cytb lineage of Haemoproteus was identified to the species level and the in vitro gametogenesis and ookinete development of Haemoproteus hirundinis was characterised. METHODS: Laboratory-reared C. nubeculosus were exposed by allowing them to take blood meals on naturally infected birds harbouring single infections of Haemoproteus belopolskyi (cytb lineage hHIICT1), Haemoproteus hirundinis (hDELURB2), Haemoproteus nucleocondensus (hGRW01) and Haemoproteus lanii (hRB1). Infected insects were dissected at intervals in order to detect sporogonic stages. In vitro exflagellation, gametogenesis and ookinete development of H. hirundinis were also investigated. Microscopic examination and PCR-based methods were used to confirm species identity. Bayesian phylogenetic inference was applied to study the relationships among Haemoproteus lineages. RESULTS: All studied parasites completed sporogony in C. nubeculosus. Ookinetes and sporozoites were found and described. Development of H. hirundinis ookinetes was similar both in vivo and in vitro. Developing ookinetes of this parasite possess long outgrowths, which extend longitudinally and produce the apical end of the ookinetes. A large group of closely related Haemoproteus species with a similar mode of ookinete development was determined. Bayesian analysis indicates that this character has phylogenetic value. The species identity of cytb lineage hDELURB2 was determined: it belongs to H. hirundinis. CONCLUSIONS: Culicoides nubeculosus is susceptible to and is a likely natural vector of numerous species of Haemoproteus parasites, thus worth attention in haemoproteosis epidemiology research. Data about in vitro development of haemoproteids provide valuable information about the rate of ookinete maturation and are recommended to use as helpful step during vector studies of haemosporidian parasites, particularly because they guide proper dissection interval of infected insects for ookinete detection during in vivo experiments. Additionally, in vitro studies readily identified patterns of morphological ookinete transformations, the characters of which are of phylogenetic value in haemosporidian parasites.


Assuntos
Haemosporida/classificação , Haemosporida/fisiologia , Filogenia , Animais , Teorema de Bayes , Doenças das Aves/parasitologia , Citocromos b/genética , Feminino , Insetos Vetores/parasitologia , Masculino , Infecções Protozoárias em Animais/transmissão
10.
Infect Genet Evol ; 75: 103978, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31352147

RESUMO

Phylogenetic inference of Hepatocystis, a haemosporidian parasite of diverse primate and bat hosts, revealed that the parasites from Australasian Pteropus bat species form a distinct clade to all other Hepatocystis parasites from Africa and Asia. Here, we investigate the phylogenetic placement of Hepatocystis in the Australian bat Pteropus poliocephalus for the first time and examine parasite morphology and prevalence from selected points across its range. Hepatocystis infections were detected in low prevalences in P. poliocephalus in contrast to high numbers in P. alecto and P. scapulatus. The prevalence in P. poliocephalus varied across its distribution range with 15% in the central biogeographic areas (central Queensland and New South Wales) and 1% in the southern-most edge (South Australia) of its range. Sequencing of five genes revealed high genetic similarity in Hepatocystis of P. poliocephalus independent of sampling location. Phylogenetic analysis placed these parasites with Hepatocystis from other Pteropus species from Australia and Asia. While numerous haplotypes were identified among sequences from the Pteropus hosts, no patterns of host specificity were recovered within the Pteropus-specific parasite group.


Assuntos
Quirópteros/parasitologia , Haemosporida/classificação , Proteínas de Protozoários/genética , Análise de Sequência de DNA/métodos , Animais , Ásia , Austrália , Haemosporida/genética , New South Wales , Filogenia , Filogeografia , Queensland
11.
Acta Trop ; 197: 105051, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31181190

RESUMO

Species of Haemoproteus (Haemosporida, Haemoproteidae) are widespread and often prevalent blood parasites of birds all over the word. They are particularly diverse in tropical countries. Due to limited knowledge of life cycles, these pathogens usually have been considered relatively benign and were neglected in veterinary medicine and bird management. However, recent molecular studies provided evidence that Haemoproteus parasites might cause severe diseases if they infect non-adapted (wrong) avian hosts due to marked damage of organs by exo-erythrocytic stages (megalomeronts). Additionally, high Haemoproteus infections are lethal to blood-sucking insects. Molecular markers are essential for reliable detection and species identification both at tissue stages in vertebrates and sporogonic stages in arthropods however, remain insufficiently developed for wildlife haemosporidian parasites. This study combined PCR-based and microscopic approaches and reported cytochrome b gene (cytb) and apicoplast gene (clpc) markers for characterization of six widespread species of haemoproteids parasitizing common birds wintering in tropics and subtropics of the Old World. Three new Haemoproteus species were described using morphological and molecular markers. Molecular characterization of haemoproteids parasitizing falcons was developed. Morphological and phylogenetic characterization of Haemoproteus tinnunculi (cytb lineage hFALSUB01), H. brachiatus (hLK03), H. parabelopolskyi (hSYAT1), H. homogeneae n. sp. (hSYAT16), H. homopicae n. sp. (hGAGLA07) and H. homominutus n. sp. (hCUKI1) was performed and provides clues for infections diagnostics. This study adds three species to the group of morphologically readily distinct Haemoproteus parasites, which differ in few base pairs (< 1%) in their partial cytb sequences, indicating that low genetic difference in such sequences often show between-species divergence and should be carefully applied in taxonomic biodiversity studies of haemosporidian parasites. Bayesian phylogenetic analysis identified the position of detected lineages in regard of other Haemoproteus species, suggesting that all reported parasites belong to subgenus Parahaemoproteus and likely are transmitted by Culicoides biting midges. Importance of clpc gene sequences was specified in haemosporidian parasite taxonomy on species levels.


Assuntos
Aves/parasitologia , Haemosporida/classificação , Haemosporida/genética , Animais , Teorema de Bayes , Citocromos b/genética , Filogenia
12.
J Parasitol ; 105(3): 446-453, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31237482

RESUMO

Birds harbor a diverse group of haemosporidian parasites that reproduce and develop in the host blood cells, muscle tissue, and various organs, which can cause negative effects on the survival and reproduction of their avian hosts. Characterization of the diversity, distribution, host specificity, prevalence patterns, and phylogenetic relationships of these parasites is critical to the study of avian host-parasite ecology and evolution and for understanding and preventing epidemics in wild bird populations. Here, we tested whether muscle and liver samples collected as part of standard ornithological museum expeditions can be examined to study the diversity and distributions of haemosporidians in the same way as blood collected from individual birds that are typically banded and released. We used a standard molecular diagnostic screening method for mitochondrial DNA (cytochrome b) of the parasites and found that blood, muscle, and liver collected from the same host individual provide similar estimates of prevalence and diversity of haemosporidians from the genera Parahaemoproteus and Leucocytozoon. Although we found higher prevalence for the genus Plasmodium when we screened blood vs. liver and muscle samples, the estimates of the diversity of Plasmodium from different tissue types are not affected at the community level. Given these results, we conclude that for several reasons existing museum genetic resources collections are valuable data sources for the study of haemosporidians. First, ornithological museum collections around the world house tens of thousands of vouchered tissue samples collected from remote regions of the world. Second, the host specimens are vouchered and thus host identification and phenotype are permanently documented in databased archives with a diversity of associated ancillary data. Thus, not only can identifications be confirmed but also a diversity of morphological measurements and data can be measured and accessed for these host specimens in perpetuity.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Biodiversidade , Aves , Sangue/parasitologia , Haemosporida/classificação , Fígado/parasitologia , Músculos/parasitologia , Museus
13.
Parasitol Res ; 118(7): 2097-2105, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31154526

RESUMO

In Germany, knowledge of disease agents transmitted by arthropods in zoological gardens is scarce. In the framework of ecological studies, mosquitoes were therefore collected in German zoological gardens and examined for mosquito-borne pathogen DNA and RNA. In total, 3840 mosquitoes were screened for filarial nematodes and three groups of viruses (orthobunyaviruses, flaviviruses, alphaviruses) while 405 mosquitoes were tested for avian malaria parasites. In addition to the filarial nematode species Dirofilaria repens (n = 1) and Setaria tundra (n = 8), Sindbis virus (n = 1) and the haemosporidian genera Haemoproteus (n = 8), Leucocytozoon (n = 10) and Plasmodium (n = 1) were demonstrated. Identified pathogens have the potential to cause disease in zoo and wild animals, but some of them also in humans. Positive mosquitoes were collected most often in July, indicating the highest infection risk during this month. Most of the pathogens were found in mosquito specimens of the Culex pipiens complex, suggesting that its members possibly act as the most important vectors in the surveyed zoos, although the mere demonstration of pathogen DNA/RNA in a homogenised complete mosquito is not finally indicative for a vector role. Outcomes of the study are not only significant for arthropod management in zoological gardens, but also for the general understanding of the occurrence and spread of mosquito-borne disease agents.


Assuntos
Culicidae/parasitologia , Filarioidea/classificação , Haemosporida/classificação , Malária Aviária/parasitologia , Mosquitos Vetores/parasitologia , Plasmodium/classificação , Animais , Culex/parasitologia , Feminino , Filarioidea/genética , Filarioidea/isolamento & purificação , Jardins , Alemanha/epidemiologia , Haemosporida/genética , Haemosporida/isolamento & purificação , Humanos , Malária Aviária/epidemiologia , Malária Aviária/transmissão , Plasmodium/genética , Plasmodium/isolamento & purificação
14.
J Parasitol ; 105(3): 414-422, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31145032

RESUMO

Avian haemosporidian parasites are particularly diverse and widespread. To date, more than 3,000 distinct cytochrome b lineages have been recorded, of which some present extremely wide geographical distributions, even including multiple continents. Whether these isolates represent one or several cryptic species remains unknown. Here we carried out a case study of SISKIN1, a common haemosporidian parasite lineage belonging to the morphologically described species Haemoproteus tartakovskyi. To shed light on its evolutionary origin, we investigated the divergence between SISKIN1 isolates obtained from siskins and redpolls in Europe (Russia and Sweden) and house finches in North America (Mexico). First, we used sequence capture of a small data set (2 Russian isolates and 1 Mexican isolate) to investigate the genetic structure based on the full-length mitochondrial genome and ∼1,000 genes. The mitochondrial genomes of Russian isolates were identical with each other but differed from the Mexican one at 6 positions. The nuclear divergence between Russian and Mexican isolates was on average 2.8%, close to what has been observed between 2 species of malaria parasites that respectively infect humans (Plasmodium falciparum) and gorillas (Plasmodium praefalciparum). Second, we used the expanded data set (15 samples in total) to investigate the genetic structure in 3 genes known to be involved in host invasion. The European isolates were identical across all sequenced genes, whereas the Mexican isolates were highly diverse. The lack of shared alleles between European and Mexican populations suggests that they might have diverged in isolation without gene flow. From the MalAvi database we examined the lineages most similar to the SISKIN1 barcode fragment (part of the cyt b gene) and found that most of them had been recorded in North and South America. This suggests that the lineage SISKIN1 originated in North America and subsequently spread to Europe. Our analyses support that the cyt b gene barcoding region is a useful marker for identification of avian haemosporidian lineages that can classify them into clusters of closely related parasites, but to further investigate species limits and evolutionary history, molecular data from multiple faster-evolving genes are required.


Assuntos
Doenças das Aves/parasitologia , Citocromos b/genética , Genoma Mitocondrial/genética , Haemosporida/classificação , Passeriformes/parasitologia , Infecções Protozoárias em Animais/parasitologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Teorema de Bayes , Doenças das Aves/transmissão , Dípteros/parasitologia , Tentilhões/parasitologia , Haemosporida/genética , Haemosporida/isolamento & purificação , Insetos Vetores/parasitologia , México , Filogenia , Filogeografia , Infecções Protozoárias em Animais/transmissão , Federação Russa , Alinhamento de Sequência/veterinária , Suécia
15.
Parasitol Res ; 118(6): 1833-1840, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989329

RESUMO

The present study assessed the prevalence and morphology of Leucocytozoon podargii from wild tawny frogmouths (Podargus strigoides) in Western Australia (WA) and genetically characterised the cytochrome b gene (cyt b) of L. podargii in wild tawny frogmouths from WA and Queensland (QLD). The prevalence of L. podargii in wild tawny frogmouths from WA was 93.3% (14/15; 95% CI, 68.1-99.8%). The morphological characters of L. podargii from WA were similar to L. podargii from QLD: the gametocytes were round-oval shape, approximately 8-12 µm in diameter; the macrogametocytes were 12.4 µm in diameter; microgametocytes were 10.4 µm in diameter; and the ratio of macrogametocytes and microgametocytes was 3:2. Sequence analysis of partial cyt b gene fragments revealed that L. podargii sequences isolated from wild tawny frogmouths in WA shared the highest similarity (99.8% at nucleotide level and 100% at protein level) with L. podargii isolated from wild tawny frogmouths in QLD. The mitochondrial 18S rRNA gene of L. podargii gametocytes was quantified using droplet digital PCR (ddPCR), and the highest gametocyte load was detected in the lung. This finding corresponds to the results of the histological study. Based on the morphological and molecular studies, it was concluded that the Leucocytozoon parasite identified from wild tawny frogmouths in WA is consistent with L. podargii from wild tawny frogmouths in QLD, and the present study has genetically characterised two different L. podargii genotypes (QLD and WA) for the first time.


Assuntos
Aves/parasitologia , Citocromos b/genética , Haemosporida/classificação , Haemosporida/genética , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Animais , DNA de Protozoário/genética , Genótipo , Filogenia , Queensland/epidemiologia , RNA Ribossômico 18S/genética , Austrália Ocidental/epidemiologia
16.
Int J Parasitol ; 49(6): 437-448, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30910465

RESUMO

Haemosporidian parasites of birds are ubiquitous in terrestrial ecosystems, but their coevolutionary dynamics remain poorly understood. If species turnover in parasites occurs at a finer scale than turnover in hosts, widespread hosts would encounter diverse parasites, potentially diversifying as a result. Previous studies have shown that some wide-ranging hosts encounter varied haemosporidian communities throughout their range, and vice-versa. More surveys are needed to elucidate mechanisms that underpin spatial patterns of diversity in this complex multi-host multi-parasite system. We sought to understand how and why a community of avian haemosporidian parasites varies in abundance and composition across elevational transects in eight sky islands in southwestern North America. We tested whether bird community composition, environment, or geographic distance explain haemosporidian parasite species turnover in a widespread host that harbors a diverse haemosporidian community, the Audubon's Warbler (Setophaga auduboni). We tested predictors of infection using generalized linear models, and predictors of bird and parasite community dissimilarity using generalized dissimilarity modeling. Predictors of infection differed by parasite genus: Parahaemoproteus was predicted by elevation and climate, Leucocytozoon varied idiosyncratically among mountains, and Plasmodium was unpredictable, but rare. Parasite turnover was nearly three-fold higher than bird turnover and was predicted by elevation, climate, and bird community composition, but not geographic distance. Haemosporidian communities vary strikingly at fine spatial scales (hundreds of kilometers), across which the bird community varies only subtly. The finer scale of turnover among parasites implies that their ranges may be smaller than those of their hosts. Avian host species should encounter different parasite species in different parts of their ranges, resulting in spatially varying selection on host immune systems. The fact that parasite turnover was predicted by bird turnover, even when considering environmental characteristics, implies that host species or their phylogenetic history plays a role in determining which parasite species will be present in a community.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/fisiologia , Infecções Protozoárias em Animais/parasitologia , Aves Canoras/parasitologia , Altitude , Animais , Distribuição Binomial , Biodiversidade , Intervalos de Confiança , DNA de Protozoário/isolamento & purificação , Clima Desértico , Florestas , Haemosporida/classificação , Haplótipos , Funções Verossimilhança , Modelos Lineares , Dinâmica não Linear , Filogenia , Infecções Protozoárias em Animais/epidemiologia , Análise de Regressão , Sudoeste dos Estados Unidos , Análise Espacial
17.
Int J Parasitol ; 49(3-4): 235-246, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30673588

RESUMO

Prevalence responses to anthropic factors differ across hosts and parasite species. We here analyzed the spatiotemporal variation of avian haemosporidian prevalence in bird assemblages of the Mooswald forest (i.e., urban greenspace; Freiburg, Germany), in response to local environmental features (e.g., water sources, human presence (visited)/absence (unvisited)) and bird-level traits (e.g., body condition, age, sex) in 2 years. We used a nested PCR protocol (mitochondrial (mt)DNA cytochrome b (cyt b) gene) and microscopy to determine haemosporidian infections. Prevalence was analyzed using a general linear multi-model (glmulti) approach with Akaike information criterion corrected for small samples (AICc), with subsequent model inferences using a GLMM on the best selected model, considering bird species as a random factor. Analyses were conducted for the main understory bird species (Blackcap - Sylvia atricapilla, Chaffinch - Coereba flaveola, Great Tit - Parus major, Blue Tit - Cyanistes caeruleus, European Robin - Erithacus rubecula, Blackbird - Turdus merula, Song Thrush - Turdus philomelos). We further conducted spatial autocorrelation analyses for all haemosporidian infections, and classification and regression trees (CARTs) for focal species. We analyzed a total of 544 samples of seven bird species. In 2011 prevalence for Haemoproteus/Plasmodium was 25.8% and 11.7% for Leucocytozoon. In 2013 prevalence for Haemoproteus/Plasmodium was 26.5% and 35.5% for Leucocytozoon. Haemosporidian prevalence was significantly different between some focal species. There was a negative association between distance to the nearest water source and prevalence in the year 2011, and the opposite pattern for the year 2013. However, when analyzed for the six focal species separately, such a relationship could change from a negative to a positive one, or there could be no relationship at all. For Leucocytozoon there was higher prevalence in the section of the forest visited by humans. We did not find spatial autocorrelation for prevalence across the study site, but there were statistically significant local spatial clusters in the visited section. Although there were similar responses of prevalence to some factors, infection patterns were generally bird species-specific. Thus, prevalence is a labile epidemiological parameter, varying spatiotemporally in an idiosyncratic way.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves , Haemosporida/classificação , Haemosporida/isolamento & purificação , Infecções por Protozoários/epidemiologia , Infecções por Protozoários/parasitologia , Animais , Cidades/epidemiologia , Alemanha/epidemiologia , Prevalência , Análise Espaço-Temporal
18.
Infect Genet Evol ; 68: 30-34, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30508688

RESUMO

Haemosporida are arthropod-borne blood parasites that infect a wide range of vertebrate hosts, including numerous species of bats. Here, we present data of haemosporidian infections in different bat species that were surveyed in Ngounié province, Gabon. We detected Nycteria parasites in Rhinolophus bats and Polychromophilus in Miniopterus minor, a rare and poorly known bat species. Strikingly, no Hepatocystis parasites, which are abundant in epauletted fruit bats elsewhere in Africa, were detected. Our findings suggest that Hepatocystis infections in bats display diverse regional patterns of distribution and transmission dynamics, that cannot be predicted from host abundance. Nycteria parasites are widely distributed in several African rhinolophid species and Polychromophilus parasites of diverse Miniopterus species worldwide belong to the same parasite species.


Assuntos
Quirópteros/parasitologia , Haemosporida , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Gabão , Genoma de Protozoário , Haemosporida/classificação , Haemosporida/genética , Filogenia , Prevalência
19.
Int J Parasitol ; 49(1): 27-36, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471285

RESUMO

A majority of avian haemosporidian diversity likely remains undiscovered, and each new recovery helps to further elucidate distributional patterns of diversification. We conducted the first known sampling of avian haemosporidians, Haemoproteus, Leucocytozoon, and Plasmodium from Benin located in tropical West Africa. We sampled 222 birds of 77 species and across distinct ecoregions with varied habitats. Haemosporidians were detected in 113 of 222 individuals, resulting in a 50.9% infection rate. By molecular analysis, we recovered a high number of novel lineages, 52.9%, and characterized the multivariate variables which influence the distributions of haemosporidian genetic lineages, including host associations and bioclimatic variables. We introduced a novel visualization method to better capture the multivariate environment of haemosporidians, and this approach resulted in the recovery of intra-generic distribution patterns of diversity, although no patterns were recovered at the genus level. Our results remain descriptive in nature, but show the promise of predictive strength with an increase in sampling localities with future work. Assessing host and bioclimatic variables at a larger geographic scale and across multiple ecoregions will help to elucidate processes regulating the distribution of haemosporidian diversity.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/classificação , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Benin/epidemiologia , Técnicas de Genotipagem , Haemosporida/genética , Especificidade de Hospedeiro , Filogeografia , Prevalência , Clima Tropical
20.
Int J Parasitol ; 49(3-4): 199-210, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30471288

RESUMO

Previous studies about geographic patterns of species diversity of avian malaria parasites and others in the Order Haemosporida did not include the avian biodiversity hotspot Madagascar. Since there are few data available on avian malaria parasites on Madagascar, we conducted the first known large-scale molecular-based study to investigate their biodiversity. Samples (1067) from 55 bird species were examined by a PCR method amplifying nearly the whole haemosporidian cytochrome b gene (1063 bp). The parasite lineages found were further characterized phylogenetically and the degree of specialization was determined with a newly introduced host diversity index (Hd). Our results demonstrate that Madagascar indeed represents a biodiversity hotspot for avian malaria parasites as we detected 71 genetically distinct parasite lineages of the genera Plasmodium and Haemoproteus. Furthermore, by using a phylogenetic approach and including the sequence divergence we suspect that the detected haemosporidian lineages represent at least 29 groups i.e. proposed species. The here presented Hd values for each parasite regarding host species, genus and family strongly support previous works demonstrating the elastic host ranges of some avian parsites of the Order Haemosporida. Representatives of the avian parasite genera Plasmodium and Leucocytozoon tend to more often be generalists than those of the genus Haemoproteus. However, as demonstrated in various examples, there is a large overlap and single parasite lineages frequently deviate from this rule.


Assuntos
Biodiversidade , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/isolamento & purificação , Infecções por Protozoários/epidemiologia , Infecções por Protozoários/parasitologia , Animais , Haemosporida/classificação , Haemosporida/genética , Madagáscar/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , Prevalência
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