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1.
Rev Bras Parasitol Vet ; 33(1): e015323, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38198362

RESUMEN

The oligochaete Dero lutzi follows a life strategy that alternates between free-living periods in aquatic environments and endoparasitic phases. Most occurrences of D. lutzi in anurans are reported in species with arboreal habits, with studies limited to the recording of the oligochaete's presence in the host. Our study recovered specimens of D. lutzi from the tree frogs Scinax fuscovarius and Scinax. nasicus. We performed a morphological assessment of the parasite using light microscopy, for the first time, scanning electron microscopy. Molecular characterization of D. lutzi was carried out using the mitochondrial gene 16S rRNA and the nuclear gene 28S rRNA. Additionally, a phylogenetic tree was constructed to assess the species´position in relation to other group members. In our results, we confirmed the phenotypic morphological characteristics of the endoparasitic phase of D. lutzi. We also presented its phylogenetic position with other oligochaetes in the group, demonstrating the proximity between the endoparasite D. lutzi and the free-living oligochaete D. superterrenus.


Asunto(s)
Oligoquetos , Parásitos , Animales , Filogenia , ARN Ribosómico 16S , Anuros
2.
An Acad Bras Cienc ; 93(2): e20201604, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33852672

RESUMEN

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.


Asunto(s)
Biodiversidad , Ecosistema , Brasil , Conservación de los Recursos Naturales , Humanos , Conocimiento
3.
J Therm Biol ; 75: 81-87, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30017056

RESUMEN

Temperature is one of the main environmental variables shaping the evolution and biology of terrestrial ectotherms. The Pantanal is the largest continuous wetland in the World. However, a lack of knowlegde still exists on the thermal ecology of terrestrial ectothems from this wetland. In this context, the thermal ecology of the lizard Tropidurus lagunablanca Carvalho, 2016 (Squamata, Tropiduridae) was investigated in the Brazilian Pantanal. The thermal ecology and microhabitat use of lizards from a riparian forest was compared to lizards from a park savanna. At both studied areas, air and body temperatures of lizards did not differ between sexes. Mean T. lagunablanca body temperatures were higher at the savanna compared to the forest, while air temperatures were similar in both habitats. The main substrates were tree trunks, with a frequency of approximately 90% of the observations. Lizards from the savanna used higher perches than those from the forest despite -in average- trees were higher at the forest. Lizard sun and shade exposure was similar for both areas. Lizards from both habitats showed similar strong linear relationships between body and air temperatures. However, lizard behaviour of using tree trunk perches differently under different sunlight situations suggests that these lizards actively thermoregulate. Further research on the thermoregulation abilities of this species, with a null hypotesis and behavioral observations will shed light on lizard thermal biology. Studies on the ecophysiological aspects of these lizards should be a priority to understand how they will react to climate change and which conservation measures will be more effective concerning their preservation.


Asunto(s)
Regulación de la Temperatura Corporal , Ecosistema , Lagartos/fisiología , Animales , Brasil , Femenino , Masculino , Temperatura
4.
Parasitol Res ; 116(7): 1907-1916, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28512673

RESUMEN

Previous studies showed infections of Hepatozoon caimani in wild populations of caimans in wide regions from Brazil; some of those demonstrated that trophic chain are linked to natural infections through paratenic hosts or by the direct ingestion of vectors. These studies life cycle of H. caimani contributed inestimably to the knowledge of transmission routes, yet but lack enhancement tools for better detail of parasite. This study reports the forms in the blood and tissues, and also partial molecular characterization of the H. caimani following part of the 18S rRNA region. In the southern Pantanal, there were sampling 39 adult caimans (Caiman yacare), where 31 (79.5%) were parasitized by H. caimani. Free gametocytes had an average intensity of 19.6% and intraerythrocytic forms 7.42%, in the blood smears. In stained smears of the liver and lungs of naturally infected caimans which were examined, monozoic and dizoic cysts were found in these tissues, generally next to the vessels. In the histopathology, meronts were observed in the wall of vessels from liver and kidney ducts. Blood samples were forwarded to PCR process and produced amplicons with about 600 and 900 bp, respectively, for the primers HEPF300/HEP900 and HEMO1/HEMO2. This was the first report of molecular confirmation of Hepatozoon in populations of naturally infected caimans of morphological detail of the gametocytes in scanning electron microscopy and histology of merogony in livers and kidneys of C. yacare.


Asunto(s)
Caimanes y Cocodrilos/parasitología , Coccidiosis/veterinaria , Eucoccidiida/crecimiento & desarrollo , Estadios del Ciclo de Vida , Animales , Brasil/epidemiología , Coccidiosis/epidemiología , Coccidiosis/parasitología , ADN Protozoario/sangre , ADN Protozoario/química , Eucoccidiida/clasificación , Eucoccidiida/genética , Eucoccidiida/ultraestructura , Filogenia , Análisis de Secuencia de ADN/veterinaria
6.
PLoS One ; 10(6): e0130075, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26102202

RESUMEN

Ecological communities are structured by both deterministic and stochastic processes. We investigated phylogenetic patterns at regional and local scales to understand the influences of seasonal processes in shaping the structure of anuran communities in the southern Pantanal wetland, Brazil. We assessed the phylogenetic structure at different scales, using the Net Relatedness Index (NRI), the Nearest Taxon Index (NTI), and phylobetadiversity indexes, as well as a permutation test, to evaluate the effect of seasonality. The anuran community was represented by a non-random set of species with a high degree of phylogenetic relatedness at the regional scale. However, at the local scale the phylogenetic structure of the community was weakly related with the seasonality of the system, indicating that oriented stochastic processes (e.g. colonization, extinction and ecological drift) and/or antagonist forces drive the structure of such communities in the southern Pantanal.


Asunto(s)
Anuros/clasificación , Filogenia , Estaciones del Año , Procesos Estocásticos , Animales , Ecosistema
7.
Biota neotrop. (Online, Ed. port.) ; 14(1): 1-9, 2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-707024

RESUMEN

The Upper Paraguay River Basin is located in the center of South America and harbors one of the largest wetland in the world, known as Pantanal. This floodplain is surrounded by uplands, which presently have most of their area converted into pastures or monocultures, besides being poorly known scientifically. Also, most of these upland areas are considered conservation priorities. Here we present a list of anuran species from a savanna-like area (municipality of Camapuã, state of Mato Grosso do Sul, Brazil) inserted in the uplands surrounding the Pantanal floodplain, in the Upper Taquari River sub-basin, and evaluate the effectiveness of the sampling effort. Data were obtained through active searches in 22 plots in aquatic habitats, during the rainy season (from December 2009 to April 2010). We found 26 species, in four families. Although sampling effort was found to sufficiently represent the local anuran assemblage, future inventories in this region should ideally include samplings during the dry and early rainy seasons, and include both active and passive capturing methods.


A bacia do Alto Paraguai, localizada no centro da América do Sul, abriga uma das maiores áreas inundáveis do mundo, conhecida como Pantanal. Essa planície alagável é rodeada por planaltos, os quais possuem grande parte de sua área convertida em pastagens ou monoculturas, além de serem pouco conhecidos cientificamente. Além disso, a maioria das áreas de planalto são consideradas prioritárias para a conservação. Apresentamos uma lista de espécies de anuros de uma área semelhante a savanas (município de Camapuã, estado de Mato Grosso do Sul, Brasil) inserida nos planaltos de entorno do Pantanal, na sub-bacia do Alto Taquari, e avaliamos a efetividade do esforço amostral. Os dados foram obtidos através de busca ativa em 22 parcelas em ambientes aquáticos, durante a estação chuvosa (de Dezembro de 2009 a Abril de 2010). Encontramos 26 espécies, em quatro famílias. Apesar de considerarmos o esforço amostral suficiente para representar da comunidade de anuros local, sugerimos que futuros inventários nessa região contemplem a estação seca e início da chuvosa, bem como o uso adicional de métodos passivos de captura.

8.
Biota neotrop. (Online, Ed. port.) ; 12(1): 99-104, Jan.-Mar. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-642994

RESUMEN

Amphibians are usually generalist predators, and their diet is influenced by extrinsic (e.g. food availability) and intrinsic factors (e.g. body size and skull shape). This study aims to describe the diet of adult males and females of Leptodactylus fuscus in the Pantanal of the Miranda river and to answer the following questions: i) Are prey's maximum size and number of food items explained by the anuran's body size? ii) Are richness of morphospecies and number of food items explained by frog sex? iii) Is there diet overlap between male and female? We recorded 62 food items, belonging to seven orders of Arthropoda, and one individual of Annelida. The diet of L. fuscus was dominated by Orthoptera, followed by Coleoptera, Araneae, Hymenoptera, Blattaria, Hemiptera and Diptera. Frog's body size did not influence prey size or number of food items consumed. The number of prey and richness of morphospecies did not differ between males and females. There was low diet overlap between the sexes. Our results provide evidence for the opportunistic and generalist feeding behavior of L. fuscus.


Anfíbios são, em geral, predadores generalistas cuja dieta é influenciada por fatores extrínsecos (e.g. disponibilidade de alimento) e intrínsecos (e.g. tamanho do corpo e formato do crânio). Este estudo tem como objetivo descrever a dieta de machos e fêmeas adultos de Leptodactylus fuscus no Pantanal do rio Miranda e responder as seguintes perguntas: i) O tamanho máximo da presa e o número de itens alimentares são explicados pelo tamanho corpóreo do anuro? ii) A riqueza de morfoespécies e número de itens alimentares são explicados pelo sexo do anuro? iii) Existe sobreposição de dieta entre macho e fêmea? Registramos 62 itens alimentares distribuídos por sete ordens de Arthropoda e um indivíduo de Annelida. A dieta de L. fuscus possui dominância de Orthoptera, seguida por Coleoptera, Araneae, Hymenoptera, Blattaria, Hemiptera e Diptera. O tamanho corpóreo do anuro não influenciou o tamanho da presa ou o número de itens alimentares consumidos. O número de presas e riqueza de morfotipos não diferiu entre machos e fêmeas. Houve baixa sobreposição alimentar entre os sexos. Os resultados mostram evidências de comportamento alimentar oportunístico e generalista para L. fuscus.

9.
J Parasitol ; 98(2): 229-35, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22088134

RESUMEN

Understanding the patterns of species distribution and abundance has been at the core of ecology. In general, these patterns are determined by species dispersion as well as by abiotic and biotic environmental conditions. Similarly, host-parasite relations and the structure of parasite assemblages are also shaped by environmental conditions and landscape composition. Herein, we assessed the influence of environmental variables and parasite species dispersion on the structure of helminth parasites communities in the frog Leptodactylus podicipinus. We sampled 10 ponds and recorded area, depth, altitude, pH, dissolved oxygen, salinity, temperature, and extent of soil, water, and vegetation cover as well as the distances between the ponds. We collected 121 frogs and found 9 helminth taxa; 2 of them were core species (prevalence higher than 50%), which contributed to the relatively high similarity observed among the ponds. Most of the helminths showed some variation in the frequencies of occurrence among communities from different ponds. The change in species composition among ponds was explained by the environmental variables but not by the distance between the ponds. Moreover, the results indicated that local processes (variation in environmental conditions) were more important than the regional processes (species distribution) in determining the structure of parasite communities. The variation in helminth communities among ponds in response to moderate differences in pond environmental characteristics points to the potential of helminth species as indicators of environmental conditions.


Asunto(s)
Anuros/parasitología , Ambiente , Helmintiasis Animal/parasitología , Helmintos/fisiología , Animales , Brasil/epidemiología , Helmintiasis Animal/epidemiología , Interacciones Huésped-Parásitos , Concentración de Iones de Hidrógeno , Oxígeno/metabolismo , Estanques , Prevalencia , Salinidad , Propiedades de Superficie
10.
Parasitol Res ; 106(3): 747-51, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20094893

RESUMEN

The importance of understanding the role of parasites in ecosystems and the structure of parasite communities was addressed by studying the helminth component community of the paradox frog Pseudis platensis. Thirty-two specimens of P. platensis were collected in the south-eastern Pantanal, State of Mato Grosso do Sul, Brazil, in March 2006 and April 2008, then surveyed for helminth parasites. The component community was composed of eight species: the trematodes Catadiscus propinquus, Catadiscus sp., Glypthelmins palmipedis, two metacercariae of undetermined species, the nematodes Cosmocerca podicipinus and Rhabdias sp., and an encysted larva. Catadiscus sp. dominated in the community with high prevalence (85.4%) and Berger Parker Index (0.75). Glypthelmins palmipedis was the second most prevalent and abundant species, while C. podicipinus and Rhabdias sp. were each found in only one host specimen. The high abundance of digeneans may be explained by the aquatic lifestyle of P. platensis. The helminth species found in this study were reported to infect other host species, corroborating the hypothesis that amphibian parasite communities are composed of generalist species. Pseudis platensis is a new host record for C. propinquus, C. podicipinus, and Rhabdias sp.


Asunto(s)
Anuros/parasitología , Nematodos/clasificación , Nematodos/aislamiento & purificación , Trematodos/clasificación , Trematodos/aislamiento & purificación , Animales , Brasil , Microscopía
11.
J Parasitol ; 93(4): 917-21, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17918376

RESUMEN

A new species of Haplometroides (Digenea, Plagiorchiidae) is described from a specimen of Phalotris nasutus (Gomes, 1915) (Serpentes, Colubridae). The host snake was obtained in the municipality of Corumbd, Mato Grosso do Sul State, Brazil. Trematodes were recovered from esophagus, stomach, and small intestine of the host. The main characteristic of the new species is the vitellaria, which is intercecal, cecal, and extracecal in the preacetabular region. A key for identification of the species in Haplometroides is proposed.


Asunto(s)
Colubridae/parasitología , Enfermedades Gastrointestinales/veterinaria , Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Animales , Brasil , Esófago/parasitología , Enfermedades Gastrointestinales/parasitología , Intestino Delgado/parasitología , Masculino , Estómago/parasitología , Trematodos/anatomía & histología , Trematodos/aislamiento & purificación , Infecciones por Trematodos/parasitología
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