Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.774
Filtrar
1.
PLoS One ; 15(10): e0240062, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33031471

RESUMO

The eukaryotic blood parasite genus Trypanosoma includes several important pathogens of humans and livestock, but has been understudied in wildlife broadly. The trypanosomes that infect birds are in particular need of increased attention, as these parasites are abundant and globally distributed, yet few studies have addressed their evolutionary origins and diversity using modern molecular and analytical approaches. Of specific interest are the deep evolutionary relationships of the avian trypanosomes relative to the trypanosome species that are pathogenic in humans, as well as their species level diversity in regions where they have been understudied such as North America. Here, we address these unresolved areas of study using phylogenomic data for two species of avian trypanosomes that were isolated as "bycatch" from host transcriptome assemblies, as well as a large 18S DNA barcode sequence dataset that includes 143 novel avian Trypanosoma 18S sequences from North America. Using a phylogenomic approach, we find that the avian trypanosomes are nested within a clade of primarily mammalian trypanosomes that includes the human pathogen Trypanosoma cruzi, and are paraphyletic with respect to the ruminant trypanosome Trypanosoma theileri. DNA barcode sequences showed that T. avium and an unidentified small, non-striated trypanosome that was morphologically similar to T. everetti are each represented by highly abundant and divergent 18S haplotypes in North America. Community-level sampling revealed that additional species-level Trypanosoma lineages exist in this region. We compared the newly sequenced DNA barcodes from North America to a global database, and found that avian Trypanosoma 18S haplotypes generally exhibited a marked lack of host specificity with at least one T. avium haplotype having an intercontinental distribution. This highly abundant T. avium haplotype appears to have a remarkably high dispersal ability and cosmopolitan capacity to evade avian host immune defenses, which warrant further study.


Assuntos
Aves/genética , Transcriptoma , Trypanosoma/genética , Animais , Teorema de Bayes , Evolução Biológica , Aves/parasitologia , Mapeamento de Sequências Contíguas , Código de Barras de DNA Taxonômico , DNA de Protozoário/química , DNA de Protozoário/metabolismo , Bases de Dados Factuais , Haplótipos , Humanos , América do Norte , Filogenia , RNA Ribossômico 18S/química , RNA Ribossômico 18S/classificação , RNA Ribossômico 18S/metabolismo , Trypanosoma/classificação , Trypanosoma/patogenicidade , Trypanosoma cruzi/classificação
2.
Rev Bras Parasitol Vet ; 29(3): e003920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027422

RESUMO

The Neotropic cormorant Nannopterum (Phalacrocorax) brasilianus (Suliformes: Phalacrocoracidae) is widely distributed in Central and South America. In Chile, information about parasites for this species is limited to helminths and nematodes, and little is known about other parasite groups. This study documents the parasitic fauna present in 80 Neotropic cormorants' carcasses collected from 2001 to 2008 in Antofagasta, Biobío, and Ñuble regions. Birds were externally inspected for ectoparasites and necropsies were performed to examine digestive and respiratory organs in search of endoparasites. Ectoparasites collected were cleared and mounted for identification under a microscope. Fecal samples were also evaluated to determine the presence of protozoan parasites employing a flotation technique. A total of 44 (42.5%) of birds were infested with at least one ectoparasite species, while 77 (96.25%) were carrying endoparasites. No protozoan forms were found after examination. Most prevalent endoparasite species found were Contracaecum rudolphii s. l. (72/80, 90%), followed by Pectinopygus gyroceras (33/80, 41.25%), and Profilicollis altmani (26/80, 32.5%). This is the first report of P. altmani, Baruscapillaria carbonis, Avioserpens sp., Cyathostoma (Cyathostoma) phenisci, and Eidmaniella pelucida in the Neotropic cormorant. These findings also expand the distributional range of Andracantha phalacrocoracis, Paradilepis caballeroi, Hysteromorpha triloba, and P. gyroceras to Chile.


Assuntos
Doenças das Aves , Aves , Parasitos , Animais , Doenças das Aves/parasitologia , Aves/parasitologia , Chile , Helmintos , Parasitos/classificação , Parasitos/fisiologia
3.
PLoS Pathog ; 16(8): e1008759, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745135

RESUMO

Ticks (order: Ixodida) are a highly diverse and ecologically important group of ectoparasitic blood-feeding organisms. One such species, the seabird tick (Ixodes uriae), is widely distributed around the circumpolar regions of the northern and southern hemispheres. It has been suggested that Ix. uriae spread from the southern to the northern circumpolar region millions of years ago and has remained isolated in these regions ever since. Such a profound biographic subdivision provides a unique opportunity to determine whether viruses associated with ticks exhibit the same evolutionary patterns as their hosts. To test this, we collected Ix. uriae specimens near a Gentoo penguin (Pygoscelis papua) colony at Neko harbour, Antarctica, and from migratory birds-the Razorbill (Alca torda) and the Common murre (Uria aalge)-on Bonden island, northern Sweden. Through meta-transcriptomic next-generation sequencing we identified 16 RNA viruses, seven of which were novel. Notably, we detected the same species, Ronne virus, and two closely related species, Bonden virus and Piguzov virus, in both hemispheres indicating that there have been at least two cross-circumpolar dispersal events. Similarly, we identified viruses discovered previously in other locations several decades ago, including Gadgets Gully virus, Taggert virus and Okhotskiy virus. By identifying the same or closely related viruses in geographically disjunct sampling locations we provide evidence for virus dispersal within and between the circumpolar regions. In marked contrast, our phylogenetic analysis revealed no movement of the Ix. uriae tick hosts between the same locations. Combined, these data suggest that migratory birds are responsible for the movement of viruses at both local and global scales.


Assuntos
Doenças das Aves/epidemiologia , Aves/parasitologia , Interações Hospedeiro-Parasita , Ixodes/fisiologia , Infecções por Vírus de RNA/virologia , Vírus de RNA/classificação , Infestações por Carrapato/veterinária , Animais , Doenças das Aves/parasitologia , Filogenia , Infecções por Vírus de RNA/genética , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
4.
Exp Appl Acarol ; 82(1): 125-135, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32856170

RESUMO

Ticks are among the best studied parasitic groups as they spread important pathogens of medical and veterinary importance worldwide. Migratory birds can play an important role in transporting ticks infected with pathogens across wide geographic regions. It is therefore important to understand which factors promote tick parasitism rates across their avian hosts and the associated potential for disease spread. Here, we identified the host attributes of infestation probability of ticks from the genus Amblyomma in 955 birds from Pantanal, Brazil. Infestation rates exhibited considerable variation across the 129 avian species surveyed and were explained by both host ecological traits and evolutionary history. The probability of an individual bird being infested with immature ticks (larvae and/or nymphs) was higher across resident bird species that forage at ground level and during the wet season. Bird species that feed on vertebrates were less likely to be infested by ticks. Other ecological traits known to promote tick exposure (age, body mass, social behavior, and sex) did not predict infestation probability. Our findings demonstrate that tick occurrence in Pantanal birds is determined by avian host attributes, but tick occurrence throughout the year constrains exposure to host-seeking ticks. Moreover, the ecology of the avian host might prevent the potential spread of tick-borne diseases outside Pantanal as migratory hosts are likely less infested by ticks.


Assuntos
Doenças das Aves , Aves/parasitologia , Estações do Ano , Infestações por Carrapato , Migração Animal , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Brasil , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Carrapatos
5.
Nature ; 584(7821): 398-402, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32759999

RESUMO

Land use change-for example, the conversion of natural habitats to agricultural or urban ecosystems-is widely recognized to influence the risk and emergence of zoonotic disease in humans1,2. However, whether such changes in risk are underpinned by predictable ecological changes remains unclear. It has been suggested that habitat disturbance might cause predictable changes in the local diversity and taxonomic composition of potential reservoir hosts, owing to systematic, trait-mediated differences in species resilience to human pressures3,4. Here we analyse 6,801 ecological assemblages and 376 host species worldwide, controlling for research effort, and show that land use has global and systematic effects on local zoonotic host communities. Known wildlife hosts of human-shared pathogens and parasites overall comprise a greater proportion of local species richness (18-72% higher) and total abundance (21-144% higher) in sites under substantial human use (secondary, agricultural and urban ecosystems) compared with nearby undisturbed habitats. The magnitude of this effect varies taxonomically and is strongest for rodent, bat and passerine bird zoonotic host species, which may be one factor that underpins the global importance of these taxa as zoonotic reservoirs. We further show that mammal species that harbour more pathogens overall (either human-shared or non-human-shared) are more likely to occur in human-managed ecosystems, suggesting that these trends may be mediated by ecological or life-history traits that influence both host status and tolerance to human disturbance5,6. Our results suggest that global changes in the mode and the intensity of land use are creating expanding hazardous interfaces between people, livestock and wildlife reservoirs of zoonotic disease.


Assuntos
Biodiversidade , Especificidade de Hospedeiro , Zoonoses/microbiologia , Zoonoses/parasitologia , Zoonoses/virologia , Animais , Aves/microbiologia , Aves/parasitologia , Aves/virologia , Humanos , Mamíferos/microbiologia , Mamíferos/parasitologia , Mamíferos/virologia , Especificidade da Espécie , Zoonoses/transmissão
6.
Exp Appl Acarol ; 81(3): 457-467, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32643110

RESUMO

Birds are recognized hosts of ticks, especially for the immature stages which may harbor various species and strains of Rickettsia. To explore landscapes inhabited by birds and their ticks would expand the knowledge on host-parasite relationships and the rickettsiae. The aim of this paper was to record the diversity of ticks collected on wild birds and assess the phylogenetic position of a novel Rickettsia strain detected in immature ticks. Birds were captured in the Ibitipoca State Park, located in the Minas Gerais state, southeastern Brazil, as part of a long-term research project on the ecology of ticks, birds and Rickettsia. We found three tick species parasitizing birds: Amblyomma aureolatum (63 larvae, 10 nymphs), Haemaphysalis leporispalustris (28 larvae, seven nymphs) and Amblyomma romarioi (27 larvae). Among these, A. aureolatum was the most abundant species including 54% (73/135) of the collected ticks. New tick-host records were: A. romarioi on Turdus amaurochalinus and H. leporispalustris on Thamnophilus caerulescens, Saltator similis and Zonotrichia capensis. Of the 82 ticks tested for Rickettsia spp. by PCR, two larvae (2.5%) of A. romarioi were infected with 'Candidatus Rickettsia paranaensis', a novel putative Rickettsia species closely related to Rickettsia africae, Rickettsia sibirica and Rickettsia parkeri, as corroborated by our phylogenetic analysis. Finally, we present a list of all records of immature stages of H. leporispalustris on passerine birds in Brazil.


Assuntos
Aves , Ixodidae , Rickettsia , Carrapatos , Animais , Animais Selvagens , Aves/parasitologia , Brasil , Filogenia , Rickettsia/genética
7.
Parasitol Res ; 119(10): 3377-3390, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32638100

RESUMO

The hypersaline lagoons located in evaporation basins or salars (salt flats) in the Atacama Desert are extreme environments harbouring a specialised biota able to survive harsh conditions for life. The knowledge of the parasitic biodiversity of these extreme habitats is still scarce despite their functional importance in regulating relevant non-economic services like habitats of waterbirds. The present study is the first report on the cestode infection of Artemia franciscana Kellogg in Salar de Atacama lagoons in northern Chile. A total of 23 parasite larvae were isolated and identified as belonging to five cestode taxa of the order Cyclophyllidea: two species of the family Hymenolepididae, i.e. Flamingolepis sp. 1 and Flamingolepis sp. 2 (adults parasitic in flamingos); two species of Dilepididae, i.e. Fuhrmannolepis averini (adults parasitic in phalaropes) and Eurycestus avoceti (adult parasitic in charadriforms birds); and one species of Progynotaeniidae, i.e. Gynandrotaenia (?) stammeri (adult parasitic in flamingos). The cysticercoids of each species are described and figured. The study represents the first geographical record of the genera Eurycestus, Gynandrotaenia and Fuhrmannolepis in South America and the first report of Gynandrotaenia and Flamingolepis in A. franciscana in its native range. This survey also contributes to the knowledge of cestodes of Phoenicopteriformes and Charadriiformes and their life cycles in the Neotropical Region. A review of cestodes recorded in brine shrimps of the genus Artemia in the world is provided. Further studies on cestode fauna of aquatic birds and their intermediate hosts in hypersaline habitats of the Neotropical Region are needed to understand their functional role in such extreme and unique ecosystems.


Assuntos
Artemia/parasitologia , Aves/parasitologia , Cestoides/crescimento & desenvolvimento , Infecções por Cestoides/veterinária , Ambientes Extremos , Animais , Aves/classificação , Cestoides/classificação , Cestoides/isolamento & purificação , Infecções por Cestoides/parasitologia , Chile , Ecossistema , Larva/classificação , Larva/crescimento & desenvolvimento , Estágios do Ciclo de Vida
9.
Proc Biol Sci ; 287(1928): 20200343, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32517623

RESUMO

To maximize their offspring success common cuckoo (Cuculus canorus) females should lay their eggs into host nests before incubation has begun. This ensures that the parasite chick hatches before all host chicks and can evict its foster siblings to monopolize host parental care. Many studies have demonstrated that most cuckoo eggs are indeed laid before the onset of host incubation. But cues used by female cuckoos to choose the right nest at the right time remain unclear. Here, we combine field observations with a field experiment to test whether female cuckoos use the number of eggs in the nests of their Oriental reed warbler (Acrocephalus orientalis) hosts to direct their choice. Over 8 years of field observations and 5 years of experiments, cuckoo females placed the majority of their eggs in nests with fewer than three host eggs, i.e. early in the laying sequence. For natural nests, the cuckoos may use information gleaned from the activity and behaviour of the host parents to make their choice. In our sets of experimental nests containing different numbers of model eggs, the vast majority of parasitism events occurred in nests containing a single egg. To our knowledge, this is the first field experiment showing that cuckoos choose host nests for parasitism based on the number of host eggs they contain. It appears that cuckoo females use the egg number to estimate the appropriate host nest stage for timely parasitism.


Assuntos
Aves/parasitologia , Comportamento de Nidação , Animais , Interações Hospedeiro-Parasita , Parasitos , Aves Canoras
10.
Rev Bras Parasitol Vet ; 29(2): e001420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520087

RESUMO

Buteogallus schistaceus (Sundevall) is an endemic bird of prey from the Amazon region, with a declining population according to international conservation agencies. The objective of this study was to report the occurrence of a parasitic nematodes in an individual treated at the Ambulatório de Animais Silvestres of Universidade Federal Rural da Amazônia, Belém campus. The animal was captured on campus and showed no resistance to capture. Fluid therapy and deworming were made, later the bird regurgited ten nematodes identified as belonging to the genus Procyrnea Chabaud (1958). Reviewing the scientific literature, it was found that so far there are no records on the helminth fauna of this bird species, which is therefore the first report of a nematode in B. schistaceus.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Nematoides/anatomia & histologia , Nematoides/classificação , Animais , Feminino , Masculino , Nematoides/isolamento & purificação
11.
Parasitol Res ; 119(7): 2337-2342, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32500371

RESUMO

Philornis flies Meinert (Diptera: Muscidae) have been documented parasitizing over 250 bird species, some of which are endemic species threatened with extinction. Philornis parasitism is hypothesized to affect nestlings disproportionately more than adult birds because limited mobility and exposed skin of nestlings increase their vulnerability to parasitism. We used a comprehensive literature review and our recent fieldwork in the Dominican Republic, Puerto Rico, and Grenada to challenge the idea that parasitism by subcutaneous Philornis species is a phenomenon primarily found in nestlings, a fact that has not been quantified to date. Of the 265 reviewed publications, 125 (49%) reported incidences of parasitism by subcutaneous Philornis, but only 12 included the sampling of adult breeding birds. Nine of these publications (75%) reported Philornis parasitism in adults of ten bird species. During fieldwork in the Dominican Republic, Puerto Rico, and Grenada, we documented 14 instances of parasitism of adult birds of seven avian species. From literature review and fieldwork, adults of at least fifteen bird species across 12 families and four orders of birds were parasitized by at least five Philornis species. In both the published literature and fieldwork, incidences of parasitism of adult birds occurred predominantly in females and was frequently associated with incubation. Although our findings indicate that Philornis parasitism of adult birds is more common than widely presumed, parasite prevalence is still greater in nestlings. In the future, we recommend surveys of adult birds to better understand host-Philornis relationships across life stages. This information may be essential for the development of effective control measures of Philornis to ensure the long-term protection of bird species of conservation concern.


Assuntos
Aves/parasitologia , Muscidae/fisiologia , Animais , Aves/classificação , Feminino , Incidência , Larva/classificação , Larva/fisiologia , Masculino , Muscidae/classificação , Comportamento de Nidação , Prevalência , Índias Ocidentais/epidemiologia
12.
Parasitol Res ; 119(8): 2511-2520, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32562066

RESUMO

Zygocotyle lunata inhabits the caecum of birds and mammals from the American continent. This amphistome parasite is easily maintained in the laboratory and serves as a model organism in life-cycle studies, but it has seldom been studied using molecular data. Neither the position of Z. lunata in the superfamily Paramphistomoidea nor the monophyly of the Zygocotylidae has been evaluated with molecular phylogenetic methods. In the present study, adult specimens of Z. lunata obtained experimentally in mice from Brazil were submitted to molecular studies. Partial sequences of nuclear (1261 bp of 28S and 418 bp of 5.8S-ITS-2) and mitochondrial (1410 bp of cytochrome c oxidase 1, cox1) markers were compared with published data. In the most well-resolved phylogeny, based on 28S sequences, Z. lunata clustered in a well-supported clade with Wardius zibethicus, the only other species currently included in the Zygocotylidae, thus confirming the validity of this family. Divergence of 28S sequences between these species was 2.2%, which falls in the range of intergeneric variation (0.9-5.6%) observed in the other two monophyletic groups in the 28S tree, i.e., representatives of Gastrodicidae and Neotropical cladorchiids (Cladorchiidae). Analysis of ITS-2 and two parts of the cox1 gene placed Z. lunata within poorly resolved clades or large polytomies composed of several paramphistomoid families, without clarifying higher-level phylogenetic relationships. The cox1 of a Brazilian isolate of Z. lunata is 99.6% similar to a Canadian isolate, confirming the pan-American distribution of the species. Finally, our phylogenetic reconstructions of Paramphistomoidea revealed a complex scenario in the taxonomic composition of some amphistome families, which highlights a need for further integrative studies that will likely result in rearrangements of traditional morphology-based classifications.


Assuntos
Doenças das Aves/parasitologia , Ceco/parasitologia , Paramphistomatidae/genética , Paramphistomatidae/isolamento & purificação , Filogenia , Infecções por Trematódeos/veterinária , Animais , Aves/parasitologia , Brasil , Canadá , Feminino , Estágios do Ciclo de Vida , Masculino , Camundongos , Paramphistomatidae/classificação , Paramphistomatidae/crescimento & desenvolvimento , Infecções por Trematódeos/parasitologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-32585999

RESUMO

Despite many studies on West Nile Virus (WNV) in the US, including the reservoir role of bird species and the summer shifts of the Culex mosquito, feeding from birds to mammals, there have been few equivalent studies in the neighboring regions of Canada where WNV is endemic. Here, a priority list of bird species likely involved in WNV transmission in the greater Montréal area is constructed by combining three sources of data: (i) from WNV surveillance in wild birds (2002-2015); (ii) blood meal analysis of Culex pipiens-restuans (CPR), the primary enzootic vectors of WNV in the region, collected from surveillance in 2008 and 2014; (iii) literature review on the sero-prevalence/host competence of resident birds. Each of these data sources yielded 18, 23 and 53 species, and overall, 67 different bird species were identified as potential WNV amplifiers/reservoirs. Of those identified from CPR blood meals, Common starlings, American robins, Song sparrows and House sparrows ranked the highest and blood meal analysis demonstrated a seasonal shift in feed preference from birds to mammals by CPR. Our study indicates that there are broad similarities in the ecology of WNV between our region and the northeastern US, although the relative importance of bird species varies somewhat between regions.


Assuntos
Aves/parasitologia , Culex , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental , Animais , Doenças das Aves/epidemiologia , Canadá , Mosquitos Vetores , Quebeque/epidemiologia , Estudos Soroepidemiológicos , Especificidade da Espécie , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária
14.
Parasitol Res ; 119(7): 2039-2045, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32377908

RESUMO

Ticks are ectoparasites that feed on blood of a broad taxonomic range of terrestrial and flying vertebrates and are distributed across a wide range of environmental conditions. Here, we explore the biotic and abiotic factors on infestation probability of ticks of the genus Amblyomma and assess the degree of host specificity based on analysis of 1028 birds surveyed across Brazil. We show that tick infestation rates exhibited considerable variation across the 235 avian species analyzed and that the probability of an individual bird being parasitized by immature ticks (larvae and nymphs) increased with annual precipitation. Host phylogeny and two host ecological traits known to promote tick exposure (body mass and foraging behavior) did not predict infestation probability. Moreover, immature ticks displayed a low degree of host specificity at the family level. Lastly, tick occurrence in birds carrying infection with avian malaria and related parasites did not differ from those free of these haemosporidian parasites, indicating a lack of parasite avoidance by immature ticks. Our findings demonstrate that tick occurrence in birds across Brazilian biomes responds to environmental factors rather than ecological and evolutionary host attributes.


Assuntos
Aves/parasitologia , Meio Ambiente , Especificidade de Hospedeiro/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Ixodidae/fisiologia , Infestações por Carrapato/veterinária , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Brasil/epidemiologia , Larva , Malária Aviária/epidemiologia , Ninfa , Filogenia
15.
Parasitol Res ; 119(7): 2129-2137, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32472382

RESUMO

Diplostomum ardeae Dubois, 1969 has seldom been reported since its description from the great blue heron (Ardea herodias L., 1758) in the USA. Sequences obtained in this study from the barcode region of cytochrome c oxidase 1 (CO1) in diplostomids from black-crowned night heron (Nycticorax nycticorax (L., 1758)) in Puerto Rico matched data from D. ardeae from A. herodias in the type region. We also obtained DNA barcodes from morphologically similar diplostomids from a rufescent tiger heron (Tigrisoma lineatum (Boddaert, 1783)) and from metacercariae from eye lenses of Trachelyopterus galeatus (Linnaeus, 1766) from the Paraná River basin in Argentina and Brazil, respectively. Barcodes matched (97-100% identity) in these South American adult and larval specimens as well as in recently published sequences from metacercariae from 11 other siluriform fishes from the same region. Barcodes from the South American species, which we describe as Diplostomum lunaschiae n. sp., differed from those of D. ardeae by 7.2-9.8%, and the new species differs from D. ardeae in its size, pharynx:oral sucker length ratio, egg:body length ratio, and distribution of vitellaria. As in prior phylogenetic analysis of CO1 sequences, both D. ardeae and D. lunaschiae n. sp. were not associated with Diplostomum. In more character-rich analyses of nuclear rDNA and of mitochondrial genomes, D. ardeae was an early divergent member of clades of species of Diplostomum. Consequently, we continue to consider D. ardeae and D. lunaschiae n. sp. members of Diplostomum, in contrast to recent suggestions that these species may belong to a different genus.


Assuntos
Aves/parasitologia , Estágios do Ciclo de Vida , Filogenia , Trematódeos/classificação , Trematódeos/crescimento & desenvolvimento , Animais , Peixes-Gato/parasitologia , Código de Barras de DNA Taxonômico , DNA Ribossômico/genética , Genoma Mitocondrial/genética , Metacercárias/classificação , Metacercárias/genética , Porto Rico , Trematódeos/anatomia & histologia , Trematódeos/genética
16.
Sci Rep ; 10(1): 8480, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439889

RESUMO

The use of a sensitive and accurate parasite detection methodology is crucial in studies exploring prevalence of parasites in host populations or communities, and uncertainty in identifying parasite genera and/or lineages may limit the understanding of host-parasite interactions. Here, we used a multistate occupancy approach that accounts for imperfect detection to assess whether sex and breeding season influenced the prevalence of a specific Haemoproteus lineage (TARUF02) in a white-lined tanager population. Likewise, we explored whether the probability of detecting the target parasite in an infected bird using PCR and sequencing analyses may be influenced by season and host sex. We found little evidence that sex influenced the probability of an individual host being infected by a haemosporidian parasite. Conversely, we found that the probability of infection by Haemoproteus TARUF02 was ~30% higher during the breeding season, reflecting a higher prevalence of this parasite in this season. The probability that PCR detects DNA of haemosporidian parasite was higher for female birds, suggesting that they are more prone to be parasitized with parasitemia levels that are more successfully detected by molecular analysis. Sequencing successfully determined the Haemoproteus TARUF02 lineage in 60% of samples collected during the breeding season and 84% of samples collected during the non-breeding season. Understanding the ecology of hosts and aspects of their physiology that may influence the parasite infection is essential to better understanding of hemoparasite infections and how parasites influence their native hosts, through decreasing reproductive success, lifespan, and/or survival.


Assuntos
Doenças das Aves/diagnóstico , Aves/parasitologia , Variação Genética , Haemosporida/isolamento & purificação , Interações Hospedeiro-Parasita , Infecções Protozoárias em Animais/diagnóstico , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves/crescimento & desenvolvimento , Feminino , Haemosporida/genética , Masculino , Prevalência , Infecções Protozoárias em Animais/parasitologia , Estações do Ano
17.
Parasitol Res ; 119(6): 1785-1793, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32318808

RESUMO

A new species of microphallid trematode was collected from the intestine of the yellow-crowned night heron Nyctanassa violacea (L.) (Pelecaniformes: Ardeidae) from Veracruz, Mexico. Maritrema kostadinovae n. sp. differs distinctly from other members of Maritrema Nicoll, 1907 from the Americas by its smaller body size (262-435 × 242-363 µm), the extension of caeca (reaching to anterior level of ventral sucker), the size and shape of the cirrus (short, tubular and unarmed) and metraterm (simple and thin-walled), the position of the genital pore (sinistrolateral to ventral sucker) and the arrangement of the vitellaria (horseshoe-shaped with posteriorly directed opening). Maximum likelihood and Bayesian inference analyses, based on partial 28S rDNA sequences, depicted M. kostadinovae n. sp. within the genus Maritrema with strong support. The new species is in a sister position to other available members of Maritrema, except for M. subdolum Jägerskiöld, 1909 that branches as the early divergent species in the Maritrema clade. The new species is the third species of Maritrema described from birds in Mexico. Comparative morphometric data for Maritrema taxa from birds and mammals from the Americas is provided.


Assuntos
Aves/parasitologia , Filogenia , Trematódeos/anatomia & histologia , Trematódeos/classificação , Infecções por Trematódeos/veterinária , Animais , DNA de Helmintos/genética , DNA Ribossômico/genética , México , Especificidade da Espécie , Trematódeos/genética , Infecções por Trematódeos/parasitologia
18.
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
19.
PLoS One ; 15(4): e0230579, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271774

RESUMO

Birds are important hosts for the first life stages of the Ixodes ricinus tick and they can transport their parasites over long distances. The aim of this study was to investigate the prevalence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Neoehrlichia mikurensis and Rickettsia helvetica in ticks collected from migratory birds in Norway. A total of 815 Ixodes ricinus ticks from 216 birds trapped at Lista Bird Observatory in southern Norway during spring and autumn migration in 2008 were analysed by real-time PCR. B. burgdorferi s. l. was the most prevalent pathogen, detected in 6.1% of the ticks. The prevalence of N. mikurensis, A. phagocytophilum and R. helvetica was 1.2%, 0.9% and 0.4% respectively. In addition, one sample (0.1%) was positive for B. miyamotoi. In total, 8.2% of the ticks were infected with at least one pathogen. Co-infection with B. burgdorferi s. l. and N. mikurensis or A. phagocytophilum was found in 6.0% of the infected ticks. Our results show that all the known major tick-borne bacterial pathogens in Norway are subject to transport by migratory birds, potentially allowing spread to new areas. Our study showed a surprisingly high number of samples with PCR inhibition (57%). These samples had been extracted using standard methodology (phenol-chloroform extraction). This illustrates the need for inhibition controls to determine true prevalence rates.


Assuntos
Doenças das Aves , Aves/parasitologia , Ixodes/microbiologia , Infestações por Carrapato/microbiologia , Doenças Transmitidas por Carrapatos/microbiologia , Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/isolamento & purificação , Anaplasmataceae/classificação , Anaplasmataceae/genética , Anaplasmataceae/isolamento & purificação , Migração Animal/fisiologia , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/microbiologia , Doenças das Aves/parasitologia , Aves/fisiologia , Borrelia/classificação , Borrelia/genética , Borrelia/isolamento & purificação , Borrelia burgdorferi/genética , Borrelia burgdorferi/isolamento & purificação , Coinfecção/epidemiologia , Coinfecção/microbiologia , DNA Bacteriano/análise , Noruega/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Rickettsia/classificação , Rickettsia/genética , Rickettsia/isolamento & purificação , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária
20.
Parasitol Res ; 119(4): 1327-1335, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32179987

RESUMO

Permanent ectoparasites live in stable environments; thus, their population dynamics are mostly adapted to changes in the host life cycle. We aimed to investigate how static and dynamic traits of red-footed falcons interplay with the dynamics of their louse subpopulations during breeding and how they affect the colonisation of new hosts by lice. We sampled red-footed falcon (Falco vespertinus) nestlings (two breeding seasons) and adults (one breeding season) in southern Hungary. The mean abundance of Colpocephalum subzerafae and Degeeriella rufa lice on the nestlings was modelled with generalized linear mixed models using clutch size and host sex in interaction with wing length. For adults, we used wing length and the number of days after laying the first egg, both in interaction with sex. D. rufa abundances increased with the nestlings' wing length. In one year, this trend was steeper on females. In adult birds, both louse species exhibited higher abundances on females at the beginning, but it decreased subsequently through the breeding season. Contrarily, abundances were constantly low on adult males. Apparently, D. rufa postpones transmission until nestlings develop juvenile plumage and choose the more feathered individual among siblings. The sexual difference in the observed abundance could either be caused by the different plumage, or by the females' preference for less parasitized males. Moreover, females likely have more time to preen during the incubation period, lowering their louse burdens. Thus, sex-biased infestation levels likely arise due to parasite preferences in the nestlings and host behavioural processes in the adult falcons.


Assuntos
Anoplura/fisiologia , Falconiformes/parasitologia , Iscnóceros/fisiologia , Ftirápteros/fisiologia , Animais , Doenças das Aves/parasitologia , Aves/parasitologia , Plumas , Feminino , Hungria , Infestações por Piolhos/parasitologia , Masculino , Asas de Animais/anatomia & histologia , Asas de Animais/parasitologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA