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1.
Parasitology ; 150(14): 1277-1285, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37246557

RESUMO

The relationships between host phylogenetics, functional traits and parasites in wildlife remain poorly understood in the Neotropics, especially in habitats with marked seasonal variation. Here, we examined the effect of seasonality and host functional traits on the prevalence of avian haemosporidians (Plasmodium and Haemoproteus) in the Brazilian Caatinga, a seasonally dry tropical forest. 933 birds were evaluated for haemosporidian infections. We found a high parasitism prevalence (51.2%), which was correlated with phylogenetic relatedness among avian species. Prevalence varied drastically among the 20 well-sampled species, ranging from 0 to 70%. Seasonality was the main factor associated with infections, but how this abiotic condition influenced parasite prevalence varied according to the host-parasite system. Plasmodium prevalence increased during the rainy season and, after excluding the large sample size of Columbiformes (n = 462/933), Plasmodium infection rate was maintained high in the wet season and showed a negative association with host body mass. No association was found between non-Columbiform bird prevalence and seasonality or body mass when evaluating both Plasmodium and Haemoproteus or only Haemoproteus infections. Parasite community was composed of 32 lineages including 7 new lineages. We evidenced that even dry domains can harbour a high prevalence and diversity of vector-borne parasites and pointed out seasonality as a ruling factor.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Infecções Protozoárias em Animais , Animais , Filogenia , Prevalência , Brasil/epidemiologia , Plasmodium/genética , Aves/parasitologia , Haemosporida/genética , Florestas , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia
2.
PeerJ ; 9: e11555, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221715

RESUMO

Avian haemosporidians are parasites with great capacity to spread to new environments and new hosts, being considered a good model to host-parasite interactions studies. Here, we examine avian haemosporidian parasites in a protected area covered by Restinga vegetation in northeastern Brazil, to test the hypothesis that haemosporidian prevalence is related to individual-level traits (age and breeding season), species-specific traits (diet, foraging strata, period of activity, species body weight, migratory status, and nest shape), and climate factors (temperature and rainfall). We screened DNA from 1,466 birds of 70 species captured monthly from April 2013 to March 2015. We detected an overall prevalence (Plasmodium/Haemoproteus infection) of 22% (44 host species) and parasite's lineages were identified by mitochondrial cyt b gene. Our results showed that migration can be an important factor predicting the prevalence of Haemoproteus (Parahaemoproteus), but not Plasmodium, in hosts. Besides, the temperature, but not rainfall, seems to predict the prevalence of Plasmodium in this bird community. Neither individual-level traits analyzed nor the other species-specific traits tested were related to the probability of a bird becoming infected by haemosporidians. Our results point the importance of conducting local studies in particular environments to understand the degree of generality of factors impacting parasite prevalence in bird communities. Despite our attempts to find patterns of infection in this bird community, we should be aware that an avian haemosporidian community organization is highly complex and this complexity can be attributed to an intricate net of factors, some of which were not observed in this study and should be evaluated in future studies. We evidence the importance of looking to host-parasite relationships in a more close scale, to assure that some effects may not be obfuscated by differences in host life-history.

3.
Parasitol Int ; 80: 102204, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33045411

RESUMO

Human induced changes on landscape can alter the biotic and abiotic factors that influence the transmission of vector-borne parasites. To examine how infection rates of vector-transmitted parasites respond to changes on natural landscapes, we captured 330 Blue-black Grassquits (Volatinia jacarina) in Brazilian biomes and assessed the prevalence and diversity of avian haemosporidian parasites (Plasmodium and Haemoproteus) across avian host populations inhabiting environment under different disturbance and climatic conditions. Overall prevalence in Blue-black Grassquits was low (11%) and infection rates exhibited considerable spatial variation, ranging from zero to 39%. Based on genetic divergence of cytochrome b gene, we found two lineages of Haemoproteus (Parahaemoproteus) and 10 of Plasmodium. We showed that Blue-black Grassquit populations inhabiting sites with higher proportion of native vegetation cover were more infected across Brazil. Other landscape metrics (number of water bodies and distance to urban areas) and climatic condition (temperature and precipitation) known to influence vector activity and promote avian malaria transmission did not explain infection probability in Blue-black Grassquit populations. Moreover, breeding season did not explain prevalence across avian host populations. Our findings suggest that avian haemosporidian prevalence and diversity in Blue-black Grassquit populations are determined by recent anthropogenic changes in vegetation cover that may alter microclimate, thus influencing vector activity and parasite transmission.


Assuntos
Doenças das Aves/epidemiologia , Haemosporida/fisiologia , Infecções Protozoárias em Animais/epidemiologia , Aves Canoras , Animais , Doenças das Aves/parasitologia , Brasil/epidemiologia , Ecossistema , Malária Aviária/epidemiologia , Malária Aviária/parasitologia , Plasmodium/fisiologia , Prevalência , Infecções Protozoárias em Animais/parasitologia
4.
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
5.
Ecology ; 100(6): e02647, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845354

RESUMO

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra- and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820-2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities.

6.
Biota Neotrop. (Online, Ed. ingl.) ; 19(4): e20180719, 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1019527

RESUMO

Abstract: Despite the great impacts of invasive wild pig (Sus scrofa) to natural ecosystems, habitat use by this species in the neotropics remains poorly studied. Here, we investigated the effects of local habitat and landscape covariates (vegetation types, running watercourses and roads) on occupancy patterns of wild pig in the Atlantic Forest of southern Brazil. We used single season occupancy modeling to estimate detection (p) and occupancy (ψ) probabilities, using 8-day camera-trap monitoring of 100 sampled sites. The cameras detected wild pig in 64 sites (naïve occupancy = 64 %). The four best models explained 72.7 % of the occupancy patterns, and the top model (with "water" variable) had a weight of 28.5 %. Even though none of the tested variables had high explanatory power of wild pig occupancy, the water variable had a negative effect trend (β = -1.124; SE = 0.734), with 59 % of occupancy when water was present and 82 % when it was absent around the sampling sites. Vestiges of the presence of wild pig in different vegetation types revealed that they used plantations of Pinus sp., native forests, and corn and oat crops. The occupation pattern shows that wild pig are generalist at our study site at the Atlantic Forest being found everywhere, raising ecological and economic concerns about the high potential negative effects of its invasion.


Resumo: Apesar dos grandes impactos da invasão do javali (Sus scrofa) nos ecossistemas naturais, o uso de hábitats por esta espécie nos neotrópicos ainda permanece pouco estudado. Aqui, nós investigamos os efeitos do hábitat local e de covariáveis da paisagem (tipos de vegetação, cursos d'água e estradas) sobre os padrões de ocupação do javali na Mata Atlântica do sul do Brasil. Utilizamos a modelagem de ocupação de estação única para estimar as probabilidades de detecção (p) e de ocupação (ψ) dos javalis, usando monitoramento de armadilha fotográfica por 8 dias em 100 locais. As câmeras detectaram javalis em 64 locais (ocupação ingênua = 64%). Os quatro melhores modelos explicaram 72,7% dos padrões de ocupação, e o melhor modelo (com variável "água") teve um peso de 28,5%. Embora nenhuma das variáveis testadas apresentaram alto poder explicativo na ocupação do javali, a variável água foi a que contribuiu com uma tendência de efeito negativo (β = -1,124; SE = 0,734), com 59% de ocupação quando a água estava presente e 82% quando estava ausente nos pontos de amostragem. Vestígios da presença de javali em diferentes tipos de vegetação revelaram que eles utilizaram plantações de Pinus sp., florestas nativas e culturas de milho e aveia. O padrão de ocupação mostra que o javali é extremamente generalista em nosso local de estudo na Mata Atlântica, sendo encontrado em todos os lugares, o que levanta preocupações ecológicas e econômicas sobre os potenciais efeitos negativos de sua invasão.

7.
Ecology ; 99(2): 497, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29266462

RESUMO

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events.

8.
PLoS One ; 12(10): e0185890, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29016633

RESUMO

Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-lined Tanager (Tachyphonus rufus) using capture-mark-recapture data from northeastern Brazil. We tested whether survival varied seasonally (breeding vs. non-breeding), with rainfall, by age and residence status in our study area. Intra-annual apparent survival was correlated with the reproductive cycle, being lower during the breeding (0.65 ± 0.16 SE) vs. the non-breeding season (0.97 ± 0.05 SE). The annual apparent survival (~0.6) was relatively low for a tropical species. In both years, we observed highest abundance in spring (November, 3.1-3.7 birds/ha) and lowest abundance in autumn-winter periods (May-August, 1.1-1.4 bird/ha). The low survival during the breeding season probably reflects the trade-off between survival and reproduction and the cost of reproduction. Our findings represent an advance in the understanding of the demography of tropical birds because we did not find a predicted high annual apparent survival, and we elucidated some aspects of intra-annual variation in survival. Further exploration of latitudinal variation in demographic traits, especially in diverse, but poorly known habitats is needed to fully vet and develop life history theories.


Assuntos
Longevidade/fisiologia , Passeriformes/fisiologia , Reprodução/fisiologia , Distribuição Animal/fisiologia , Animais , Brasil , Feminino , Masculino , Chuva , Floresta Úmida , Estações do Ano
9.
An Acad Bras Cienc ; 87(1): 121-36, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25806980

RESUMO

The Epinephelidae form a group of species of high biological and economical interests. It´s phylogeographic patterns are not well known especially the distributed populations in the western region of the Atlantic Ocean. Among the representatives is a small species called Cephalopholis fulva, Coney, which presents a wide geographical distribution, polychromia, hermaphroditism and is quickly becoming a large target for the exploration of commercial fishing. The genetic and historical demography were obtained through the partial sequence analysis of Control Region from six locations on the coastline of Brazil from the northeast coast to the southwest coast, including the oceanic islands of Rocas Atoll and Fernando de Noronha Archipelago. The analyzed samples revealed a high genetic variability and a strong gene flow among the sampled locations. Additionally, the genetic data revealed that population expansions probably occurred due to the changes in the sea levels that occurred during the Pleistocene. The large population connectivity found in Coney constitutes relevant conditions for their biological conservation.


Assuntos
Peixes/genética , Variação Genética , Animais , Oceano Atlântico , Brasil , DNA Mitocondrial/genética , Peixes/classificação , Fluxo Gênico , Filogenia , Filogeografia , Dinâmica Populacional
10.
Rev Bras Parasitol Vet ; 22(2): 300-1, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23778828

RESUMO

The present paper reports the occurrence of Microlynchia pusilla in the state of Rio Grande do Norte (RN) on Leptotila verreauxi approximans from a deciduous forest fragment located in the municipality of Macaíba. A specimen of L. v. approximans was collected in June 2012, wrapped in paper towels and kept under refrigeration in a plastic bag for later analysis of parasite fauna, taxidermy, and eventual storage in the Ornithological Collection of the Federal University of Rio Grande do Norte (UFRN). During the search for ectoparasites, a specimen of M. pusilla was found among feathers of the ventral region; it was collected and stored in the Entomological Collection 'Adalberto Antônio Varela-Freire' of the same university. This report extends the knowledge about geographical distribution and confirms the association of M. pusilla with hosts Columbiformes, contributing to the knowledge of the family Hippoboscidae in the country.


Assuntos
Dípteros , Animais , Brasil
11.
Rev. bras. parasitol. vet ; 22(2): 300-301, Apr.-June 2013.
Artigo em Inglês | LILACS, VETINDEX | ID: lil-679433

RESUMO

The present paper reports the occurrence of Microlynchia pusilla in the state of Rio Grande do Norte (RN) on Leptotila verreauxi approximans from a deciduous forest fragment located in the municipality of Macaíba. A specimen of L. v. approximans was collected in June 2012, wrapped in paper towels and kept under refrigeration in a plastic bag for later analysis of parasite fauna, taxidermy, and eventual storage in the Ornithological Collection of the Federal University of Rio Grande do Norte (UFRN). During the search for ectoparasites, a specimen of M. pusilla was found among feathers of the ventral region; it was collected and stored in the Entomological Collection 'Adalberto Antônio Varela-Freire' of the same university. This report extends the knowledge about geographical distribution and confirms the association of M. pusilla with hosts Columbiformes, contributing to the knowledge of the family Hippoboscidae in the country.


Este trabalho registra a ocorrência de Microlynchia pusilla no estado do Rio Grande do Norte em Leptotila verreauxi approximans oriunda de um fragmento de floresta estacional decidual localizado no município de Macaíba. Um espécime de L. v. approximans foi coletado em junho de 2012, envolvido em papel toalha e conservado sob refrigeração em saco plástico para posterior análise da fauna parasitária, taxidermia e depósito na Coleção Ornitológica da Universidade Federal do Rio Grande do Norte (UFRN). Durante a busca por ectoparasitos foi encontrado um espécime de M. pusilla nas penas da região ventral, o qual foi coletado e depositado na Coleção Entomológica Adalberto Antônio Varela-Freire da mesma universidade. Este relato amplia o conhecimento sobre a distribuição geográfica de M. pusilla e confirma sua associação com hospedeiros Columbiformes, contribuindo para o conhecimento da família Hippoboscidae no país.


Assuntos
Animais , Dípteros , Brasil
12.
Mem Inst Oswaldo Cruz ; 98(1): 93-102, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12700867

RESUMO

During an ecological study, carried out between 1994 and 1996 with Streptoprocne biscutata (Sclater) (Apodiformes: Apodidae) birds, that inhabit caves in the Quatro Barras County, State of Paran , Southern Brazil, a new tick species of the subgenus Multidentatus was observed. The female, male, nymph, and larva of Ixodes (Multidentatus) paranaensis n. sp., are described. Of the 12 known species of the subgenus Multidentatus, only I. (M.) auritulus Neumann, 1904 and I. (M.) murreleti Cooley and Kohls, 1945 occur in the Neartic region and only I. (M.) auritulus occurs in the Neotropical region. As such, I. (M.) paranaensis n. sp. increases the number of species and the distribution area of the subgenus Multidentatus in the Americas.


Assuntos
Aves/parasitologia , Ixodes/anatomia & histologia , Animais , Brasil , Feminino , Ixodes/classificação , Larva/anatomia & histologia , Masculino , Ninfa/anatomia & histologia
13.
Mem. Inst. Oswaldo Cruz ; 98(1): 93-102, Jan. 30, 2003. ilus
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: lil-331387

RESUMO

During an ecological study, carried out between 1994 and 1996 with Streptoprocne biscutata (Sclater) (Apodiformes: Apodidae) birds, that inhabit caves in the Quatro Barras County, State of Paraná, Southern Brazil, a new tick species of the subgenus Multidentatus was observed. The female, male, nymph, and larva of Ixodes (Multidentatus) paranaensis n. sp., are described. Of the 12 known species of the subgenus Multidentatus, only I. (M.) auritulus Neumann, 1904 and I. (M.) murreleti Cooley and Kohls, 1945 occur in the Neartic region and only I. (M.) auritulus occurs in the Neotropical region. As such, I. (M.) paranaensis n. sp. increases the number of species and the distribution area of the subgenus Multidentatus in the Americas


Assuntos
Animais , Masculino , Feminino , Aves , Ixodes , Brasil , Ixodes , Larva , Ninfa
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