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1.
Ecol Evol ; 13(10): e10624, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37869432

RESUMO

Agricultural commodity production is one the main drivers of deforestation in Legal Brazilian Amazonia resulting in a deforested and/or fragmented landscape formed by forest remnants of different sizes and shape embedded within the agricultural matrix. As an ecosystem engineer and a crucial seed predator, white-lipped peccaries (Tayassu pecari) play a pivotal role in forest structure, biodiversity, and nutrient cycling. However, they are highly sensitive to habitat fragmentation and hunting pressure. White-lipped peccaries are, therefore, a wide-ranging "landscape species," the spatial and ecological requirements of which can be used to guide conservation planning in human-modified landscapes. Using data from GPS-tracked individuals in large-scale mechanized agriculture landscapes in the state of Mato Grosso, Brazil's largest soybean and maize producer, we investiated the home range size and resource selection during both the crop and non-crop season. We observed a seasonal variation in home range size and an increased selection for croplands during the crop season. White-lipped peccaries favored native vegetation patches and also exhibited avoidance of locations distant from perennial water bodies and distant cropland locations far from forest remmants. This study can contribute to inform effective conservation strategies and land management practices aimed at preserving suitable habitats and promoting wildlife coexistence with working agricultural landscapes.

2.
Arch Environ Contam Toxicol ; 85(1): 34-45, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37355496

RESUMO

Mercury is a global contaminant found in the Amazon; it can be biomagnified in the aquatic trophic chain. The use of piscivorous birds for biomonitoring of mercury contamination is increasing, mainly due to the non-mobility of mercury in bird feathers. We examined the concentrations of total mercury and methylmercury in different tissues of the green kingfisher, Chloroceryle americana collected from the Teles Pires and Juruena Rivers in the southern Brazilian Amazon. We also evaluated total mercury in small Characidae fish (potential C. americana food) in the same areas. The results indicate contamination of the birds with high concentrations, on average two-times higher in the green kingfishers from the Teles Pires River compared to the Juruena River; the same results were found for the fish specimens. Fifty-eight per cent of the feather samples from the Juruena River and 90% from the Teles Pires River had total mercury concentrations above 5 µg/g, a level previously associated with adverse effects related to bird breeding. The methylmercury concentration was lowest in the liver, followed by feathers and highest in muscle. Although Juruena River bird feathers had a lower total mercury concentration, > 96% of the total mercury was methylmercury, the highest amount for specimens from both rivers. Although the concentration of Hg in the muscle of the green kingfisher is higher when compared to the feather and liver, the non-invasive monitoring through analysis of samples of feathers is an efficient biomonitoring tool for evaluation of mercury contamination in tropical birds.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Mercúrio/análise , Espécies Sentinelas , Monitoramento Ambiental , Aves , Peixes , Plumas/química
3.
Mol Ecol Resour ; 22(3): 962-977, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34601818

RESUMO

Metabarcoding of environmental DNA (eDNA) is now widely used to build diversity profiles from DNA that has been shed by species into the environment. There is substantial interest in the expansion of eDNA approaches for improved detection of terrestrial vertebrates using invertebrate-derived DNA (iDNA) in which hematophagous, sarcophagous, and coprophagous invertebrates sample vertebrate blood, carrion, or faeces. Here, we used metabarcoding and multiple iDNA samplers (carrion flies, sandflies, and mosquitos) collected from 39 forested sites in the southern Amazon to profile gamma and alpha diversity. Our main objectives were to (1) compare diversity found with iDNA to camera trapping, which is the conventional method of vertebrate diversity surveillance; and (2) compare each of the iDNA samplers to assess the effectiveness, efficiency, and potential biases associated with each sampler. In total, we collected and analysed 1759 carrion flies, 48,686 sandflies, and 4776 mosquitos. Carrion flies revealed the greatest total vertebrate species richness at the landscape level, despite the least amount of sampling effort and the fewest number of individuals captured for metabarcoding, followed by sandflies. Camera traps had the highest median species richness at the site-level but showed strong bias towards carnivore and ungulate species and missed much of the diversity described by iDNA methods. Mosquitos showed a strong feeding preference for humans as did sandflies for armadillos, thus presenting potential utility to further study related to host-vector interactions.


Assuntos
Código de Barras de DNA Taxonômico , Dípteros , Monitoramento Ambiental , Vertebrados , Animais , Biodiversidade , Culicidae , Código de Barras de DNA Taxonômico/métodos , Humanos , Psychodidae/genética , Vertebrados/genética
4.
Ecology ; 103(1): e03543, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34841521

RESUMO

Energetic subsidies between terrestrial and aquatic ecosystems can strongly influence food webs and population dynamics. Our objective was to study how aquatic subsidies affected jaguar (Panthera onca) diet, sociality, and population density in a seasonally flooded protected area in the Brazilian Pantanal. The diet (n = 138 scats) was dominated by fish (46%) and aquatic reptiles (55%), representing the first jaguar population known to feed extensively on fish and to minimally consume mammals (11%). These aquatic subsidies supported the highest jaguar population density estimate to date (12.4 jaguars/100 km²) derived from camera traps (8,065 trap nights) and GPS collars (n = 13). Contrary to their mostly solitary behavior elsewhere, we documented social interactions previously unobserved between same-sex adults including cooperative fishing, co-traveling, and play. Our study demonstrates that aquatic subsidies, frequently described in omnivores, can also transform the ecology and behavior of obligate carnivores.


Assuntos
Ecossistema , Panthera , Animais , Ecologia , Densidade Demográfica , Comportamento Predatório , Brasil
5.
Biota Neotrop. (Online, Ed. ingl.) ; 22(3): e20211280, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1383933

RESUMO

Abstract The process of exotic species introduction is recognized as one of the greatest threats to the ecology and economy of the planet, due to changes in interactions in native biological communities. In this sense, reporting bioinvasions is the first step to understanding its introduction process and creating strategies to mitigate possible socio-environmental damages. Here we report the first records of Podocnemis unifilis introduced in the Northern Pantanal, Mato Grosso, Brazil. We obtained the species' first records occasionally during 2014 and 2015. In the following years from 2016 to 2019, we carried out systematic observations through nautical incursions on the Paraguay River, between the Sepotuba River mouth and the Taiamã Ecological Station (TES). We also included third part records, when it was possible to prove the species identification and registration sites. Podocnemis unifilis adults, hatchling and nests were recorded at different points along the Paraguay River. Our results indicate that P. unifilis was introduced close to the urban nucleus of Cáceres about 30 years ago. Currently, it has an established population, recording nests and hatchling for years in a row. A particular one is its occurrence at the TES, an important natural fish nursery and refuge for the wetland fauna. Thus, continuous monitoring is suggested from P.unifilis, since the Pantanal's environment with several different aquatic environments, offers favorable conditions for the species population increase in the Northern Pantanal.


Resumo O processo de introdução de espécies exóticas é reconhecido como uma das maiores ameaças à ecologia e economia do planeta, devido às mudanças nas interações em comunidades biológicas nativas. Nesse sentido, relatar as bioinvasões é o primeiro passo para entender seu processo de implantação e criar estratégias para mitigar possíveis danos socioambientais. Aqui relatamos os primeiros registros de P. unifilis introduzidos no Pantanal Norte, Mato Grosso, Brasil. Obtivemos os primeiros registros das espécies ocasionalmente durante 2014 e 2015. Nos anos seguintes, de 2016 a 2019, realizamos observações sistemáticas por meio de incursões náuticas no rio Paraguai, entre a foz do rio Sepotuba e a Estação Ecológica Taiamã (TES). Incluímos também registros de terceiros, quando foi possível comprovar os locais de identificação e registro das espécies. Adultos de Podcnemis unifilis, filhotes e ninhos foram registrados em diferentes pontos ao longo do rio Paraguai. Nossos resultados indicam que P. unifilis foi introduzido próximo ao núcleo urbano de Cáceres há cerca de 30 anos. Atualmente, ela tem uma população estabelecida, registrando ninhos e filhotes por anos consecutivos. Uma em particular é a sua ocorrência no TES, importante viveiro natural de peixes e refúgio da fauna pantaneira. Assim, sugere-se o monitoramento contínuo de P.unifilis, uma vez que o ambiente do Pantanal com diversos ambientes aquáticos distintos, oferece condições favoráveis para o aumento da população da espécie no Pantanal Norte.

6.
Sci Total Environ ; 754: 141730, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920380

RESUMO

The evaluation of mercury (Hg) toxicity in wildlife species has prompted a search for sensitive indicators to accurately measure the body burden of Hg. Despite the extensive use of feathers as an indicator of Hg in birds, they do not appear to be an entirely suitable indicator of the extent of contamination in certain conditions and bird species since Hg levels are influenced by the growth period, timing of the last moult and migration. This research aimed to evaluate rhamphotheca as a potential indicator of environmental Hg concentrations in seabirds. We used culled yellow-legged gulls (Larus michahellis) (n = 20) and determined THg in rhamphotheca and feathers. We distinguished between upper and lower rhamphotheca, and divided each one into 16 equal portions along the culmen to analyse their THg content spatially. In each bird, THg was also determined in primary (P1) and secondary (S8) feathers and compared with rhamphotheca. The median (25th, 75th percentile) rhamphotheca Hg concentration was 13.44 (9.63, 17.46) µg/g, which was twofold higher than in the feathers 7.56 (4.88, 12.89) µg/g. Median THg in rhamphotheca was significantly higher (p < 0.05) in females 15.05 (10.35, 23.04) µg/g than in males 12.34 (8.57, 15.19) µg/g, whereas no differences (p > 0.05) were found in the feathers. No significant differences in Hg levels were found between upper and lower beak mandibles or along either. In contrast, significant differences in Hg concentrations were found between the P1 and S8 feathers (mean, 12.04 vs. 6.04 µg/g). No correlation was found between Hg content in rhamphotheca and feathers. Mercury levels in rhamphotheca exhibited stronger significant relationships with weight (R2 = 0.568), length (R2 = 0.524) and culmen (R2 = 0.347) than the levels in the feathers, which showed no correlation. Overall, our results suggest that rhamphotheca is a suitable tissue indicator for Hg monitoring in gulls; however, further studies are needed to extend our research to other bird species.


Assuntos
Poluentes Ambientais , Mercúrio , Animais , Aves , Monitoramento Ambiental , Poluentes Ambientais/análise , Plumas/química , Mercúrio/análise
7.
PLoS One ; 15(3): e0230209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32160257

RESUMO

Agricultural frontier expansion into the Amazon over the last four decades has created million hectares of fragmented forests. While many species undergo local extinctions within remaining forest patches, this may be compensated by native species from neighbouring open-habitat areas potentially invading these patches, particularly as forest habitats become increasingly degraded. Here, we examine the effects of habitat loss, fragmentation and degradation on small mammal assemblages in a southern Amazonian deforestation frontier, while accounting for species-specific degree of forest-dependency. We surveyed small mammals at three continuous forest sites and 19 forest patches of different sizes and degrees of isolation. We further sampled matrix habitats adjacent to forest patches, which allowed us to classify each species according to forest-dependency and generate a community-averaged forest-dependency index for each site. Based on 21,568 trap-nights, we recorded 970 small mammals representing 20 species: 12 forest-dependents, 5 matrix-tolerants and 3 open-habitat specialists. Across the gradient of forest patch size, small mammal assemblages failed to show the typical species-area relationship, but this relationship held true when either species abundance or composition was considered. Species composition was further mediated by community-averaged forest-dependency, so that smaller forest patches were occupied by a lower proportion of forest-dependent rodents and marsupials. Both species richness and abundance increased in less isolated fragments surrounded by structurally simplified matrix habitats (e.g. active or abandoned cattle pastures). While shorter distances between forest patches may favour small mammal abundances, forest area and matrix complexity dictated which species could persist within forest fragments according to their degree of forest-dependency. Small mammal local extinctions in small forest patches within Amazonian deforestation frontiers are therefore likely offset by the incursion of open-habitat species. To preclude the dominance of those species, and consequent losses of native species and associated ecosystem functions, management actions should limit or reduce areas dedicated to pasture, additionally maintaining more structurally complex matrix habitats across fragmented landscapes.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/tendências , Mamíferos , Animais , Brasil , Ecossistema , Espécies em Perigo de Extinção/tendências , Florestas , Dinâmica Populacional , Floresta Úmida , Rios , Especificidade da Espécie , Árvores
8.
Transbound Emerg Dis ; 67(3): 1045-1051, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31793244

RESUMO

In order to determine whether southern Amazonian bats could harbour hantaviruses we, serologically and molecularly, screened blood, saliva, excreta and organ tissues of 47 bats captured from September to December 2015. We found that only phyllostomid bats presented antibodies against hantavirus. The seropositive bats belonged to two species of Phyllostomid bats: the greater spear-nosed bat Phyllostomus hastatus (omnivorous) and the gnome fruit-eating bat Dermanura gnoma. The overall seroprevalence was of 4.2%. Therefore, we show here that hantaviruses are circulating among phyllostomid bats in the Amazonian arc of deforestation.


Assuntos
Anticorpos Antivirais/sangue , Quirópteros/virologia , Infecções por Hantavirus/veterinária , Orthohantavírus/imunologia , Animais , Brasil/epidemiologia , Quirópteros/imunologia , Monitoramento Epidemiológico , Feminino , Florestas , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Masculino , Estudos Soroepidemiológicos
9.
Full dent. sci ; 11(41): 64-68, 2019. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-1052015

RESUMO

As comunicações oroantrais são complicações comuns, geralmente relacionadas a exodontias de dentes superiores posteriores devido ao íntimo contato dos ápices radiculares destes com o assoalho do seio maxilar. Seu diagnóstico é baseado na história clínica e em achados imaginológicos. O presente trabalho objetiva revisar a literatura para demonstrar as facilidades, além de vantagens e desvantagens da utilização da bola de Bichat no fechamento de comunicações bucossinusais, apresentando um caso clínico utilizando essa técnica (AU).


The oroantral communication is a common complication, often related to extractions of posterior maxillary teeth due to close contact with the shoot tips root of the floor of the maxillary sinus. Its diagnosis is based on clinical history and imaging findings. This study aims to review the literature to demonstrate the facilities, as well as advantages and disadvantages of the use of the Bichat ball at close of oroantral communication, presenting one clinical case using this technique (AU).


Assuntos
Humanos , Masculino , Adulto , Retalhos Cirúrgicos , Corpo Adiposo , Fístula Bucoantral , Retalhos de Tecido Biológico , Brasil
10.
ROBRAC ; 26(79): 86-91, out./dez. 2017. ilus
Artigo em Português | LILACS | ID: biblio-884507

RESUMO

O fibroma odontogênico central é definido como uma neoplasia benigna dos maxilares caracterizada por apresentar uma quantidade variável de epitélio odontogênico inativo em meio a um estroma de tecido conjuntivo fibroso. É considerada uma neoplasia rara que representa de 0% a 5,5% de todos os tumores odontogênicos na maioria dos estudos retrospectivos encontrados na literatura. Acomete pacientes em uma ampla faixa etária com certa predominância em indivíduos do sexo feminino. Apresenta-se, na grande maioria dos casos, como uma lesão de crescimento lento e assintomático que pode promover abaulamento das corticais ósseas adjacentes. Do ponto de vista radiográfico, aparece, tipicamente, sob a forma de uma imagem radiolúcida uni ou multilocular com margens bem definidas, podendo apresentar focos de calcificação em seu interior. O fibroma odontogênico central é subdividido histologicamente em tipo simples (pobre em epitélio) e tipo OMS (rico em epitélio). A lesão responde bem ao tratamento cirúrgico conservador por enucleação associada à curetagem, sendo as recidivas muito incomuns. Esse trabalho tem o objetivo de fazer uma breve revisão de literatura a respeito das características epidemiológicas, clínico-imaginológicas e histopatológicas desta lesão e relatar um caso diagnosticado num paciente do sexo masculino, 13 anos, com queixa de aumento de volume em mento. Os exames de imagem evidenciaram a presença de defeito osteolítico bem delimitado em região de sínfise mandibular associado aos elementos dentários 33 e 43 que se apresentavam inclusos. A lesão foi submetida à enucleação e curetagem. O paciente encontra-se em proservação há dois anos sem sinais de recidiva da lesão.


The central odontogenic fibroma is defined as a benign neoplasm of the jaws characterized by having a variable amount of inactive odontogenic epithelium in the midst of a fibrous connective tissue stroma. It is considered a rare neoplasm that is from 0% to 5.5% of all odontogenic tumors in most retrospective studies found in the literature. Affects patients in a wide age range with a certain predominance in females. , Is shown in most cases, as a slow-growing lesions and asymptomatic which can promote the bulging adjacent cortical bone. The radiographic point of view, appears typically in the form of an image radiolucent uni or multilocular with well-defined margins and may have foci of calcification inside. The central odontogenic fibroma is subdivided histologically in simple type (poor epithelium) and WHO type (rich in epithelium). The injury responds well to conservative treatment by surgical enucleation associated with curettage, and the very unusual relapses. This work aims to make a brief review of literature on the epidemiological, clinical and histopathological imaginological this injury and to report a case diagnosed in a male patient, 13, with volume up complaint ment. Imaging tests showed the presence of well-defined osteolytic defect in mandibular symphysis region associated with dental elements 33 and 43 who performed included. The lesion was submitted to enucleation and curettage. The patient is under observation for two years without signs of recurrence.

11.
Environ Sci Pollut Res Int ; 24(28): 22709-22716, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28815370

RESUMO

Although the impacts of large dams on freshwater biota are relatively well known, the effects of small hydropower plants (SHP) are not well investigated. In this work, we studied if mercury (Hg) concentrations in fish rise in two tropical SHP reservoirs, and whether similar effects take place during impoundment. Total Hg concentrations in several fish species were determined at two SHP in the Upper Guaporé River basin floodplain, Brazil. In total, 185 specimens were analysed for Hg content in dorsal muscle and none of them reported levels above the safety limit (500 µg kg-1) for fish consumption recommended by the World Health Organisation (WHO). The highest levels of Hg (231 and 447 µg kg-1) were found in carnivorous species in both reservoirs. Mercury increased as a function of standard length in most of the fish populations in the reservoirs, and higher Hg concentrations were found in fish at the reservoir compared with fish downstream. The high dissolved oxygen concentrations and high transparency of the water column (i.e. oligotrophic reservoir) together with the absence of thermal stratification may explain low Hg methylation and low MeHg levels found in fish after flooding. Overall, according to limnological characteristics of water, we may hypothesise that reservoir conditions are not favourable to high net Hg methylation.


Assuntos
Monitoramento Ambiental/métodos , Peixes/metabolismo , Mercúrio/análise , Compostos de Metilmercúrio/análise , Centrais Elétricas , Poluentes Químicos da Água/análise , Animais , Brasil , Músculos/química , Rios/química
12.
Primates ; 58(3): 441-448, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28213677

RESUMO

Historical records of Ateles chamek (black-faced black spider monkey) suggest that the species range extends further south of the known species distribution, within an ecotonal region between the Amazonia, Cerrado and Pantanal biomes in Brazil. Ecotones are zones of habitat transition with high species richness that remain undersampled as conservationists often prioritize biodiversity hotspots. Thus, distribution ranges may be inaccurately measured when species occur in ecotonal zones. We report the first precise records of A. chamek in 24 new localities surveyed in the ecotonal zone of the Upper Paraguay River Basin, and we present subgroup encounter rates in the 11 largest patches (>70 ha) along 207 km of the line transects surveyed. The new records represent an expansion of the distribution of A. chamek approximately 200 km to the south, increasing the known extent of its occurrence by 10.8%. Local tributaries may not be barriers for spider monkeys, which are able to swim and cross slow-moving rivers. However, the dry forests of the Cerrado and the flooded areas of the Pantanal, formed by grassland and scarce trees, may be habitat barriers for A. chamek. The populations living in this ecotonal zone are relatively abundant (1.1-6.67 subgroup sightings/10 km) compared to the heavily hunted continuous forests of northern Amazonia. Furthermore, these values are similar to those for other Ateles spp. inhabiting forests with low or no hunting pressure. We highlight the need for specific conservation action to protect the spider monkeys living in these landscapes, which are threatened by agriculture expansion.


Assuntos
Atelinae , Ecossistema , Animais , Brasil , Paraguai , Rios
13.
Environ Geochem Health ; 38(3): 713-22, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26337755

RESUMO

This study evaluated the risk to human health from mercury (Hg) exposure through fish consumption in the Pantanal, Brazil. In order to address these risks, Hg concentrations and accumulation patterns were determined in target organs of predatory fish (Crenicichla lepidota and Pygocentrus nattereri). Levels of Hg were analysed during the two phases of the flood pulse (flood and drought) in fish from different local ecosystems, such as the Bento Gomes and Paraguay rivers. Although the former study area is directly affected by gold mining, a higher, but not significantly different, Hg concentration in fish was found compared with fish at the Paraguay River, which is regarded as pristine area. Moreover, no seasonal variability was found in either river. Although total mercury levels in fish did not exceed the maximum FAO/WHO threshold (0.5 µg g(-1)), according to dietary habits in riverine communities of the Pantanal (up to 6 oz of fish per day), there is reason for concern over the potential for deleterious health effects that could be caused by high Hg intake. In fact, the estimated daily intake in the present study ranged from 0.49 to 1.08 µg Hg kg(-1) day(-1), for adults (including women of childbearing age) and children, respectively. Because of high Hg intakes in riverine groups, which exceed the recommended reference dose value, these communities could be considered at risk. Therefore, it is necessary to consider regulatory measures and public education regarding fish consumption, particularly in vulnerable groups (i.e. children, pregnant women and women of childbearing age).


Assuntos
Contaminação de Alimentos/análise , Mercúrio/análise , Medição de Risco , Adulto , Animais , Brasil/epidemiologia , Caraciformes , Criança , Ciclídeos , Feminino , Inundações , Humanos , Masculino , Intoxicação por Mercúrio/epidemiologia
14.
Chemosphere ; 138: 25-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26026900

RESUMO

Mercury (Hg) is a ubiquitous environmental contaminant that poses potential threats to ecosystems due to its toxicity to humans and wildlife. The development of non-lethal sampling techniques is a critical step for evaluation of Hg in threatened species in tropical floodplain environments, where most of Hg found is the result of land use and gold mining activities, and more methylation sites are available. We evaluated the spatial and seasonal effectiveness of caudal scutes and claws to estimate Hg bioaccumulation in crocodilians (Caiman yacare), in the scarcely documented Pantanal. Hence, we investigated the potential for Hg bioaccumulation in top predators according to its proximity to mining sites, and in water bodies with different hydrological characteristics and connectivity with the main river during two phases of the flood pulse (dry and flood). The highest Hg concentrations were detected in caimans captured close to mining activities, in claws (2176 ng g(-1) ww) and caudal scutes (388 ng g(-1) ww). THg concentration in claws was related to the flood season and its mean concentration was thirteen fold higher than Hg concentration in scutes during whole year. Both tissues were found to be effective as non-lethal sampling techniques for measuring Hg bioaccumulation in reptiles over time. Nevertheless, claw tissue seems to have a more consistent result, since its constitutional chemical characteristics makes it a better indicator of spatial patterns that influence on Hg exposure.


Assuntos
Jacarés e Crocodilos/metabolismo , Monitoramento Ambiental/métodos , Mercúrio/análise , Manejo de Espécimes/métodos , Poluentes Químicos da Água/análise , Animais , Brasil , Ecossistema , Humanos , Mercúrio/farmacocinética , Mineração , Rios/química , Estações do Ano , Poluentes Químicos da Água/farmacocinética
15.
Acta amaz ; 45(2): 187-194, abr.-jun. 2015. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455247

RESUMO

The effectiveness of ecological researches on small mammals strongly depends on trapping techniques to survey communities and populations accurately. The main goal of this study was to assess the efficiency of three types of traps (Sherman, Tomahawk and Pitfall) to capture non-volant small mammals. We installed traps in 22 forest fragments in the southern Brazilian Amazonia. We captured 873 individuals belonging to 21 species; most of the individuals (N = 369) and species (N = 19) were trapped using Pitfalls, followed by Shermans (N = 271 individuals; N = 15 species) and Tomahawks (N = 233 individuals; N = 15 species). Pitfalls trapped a richer community subset of small mammals than the two other types of traps, and a more abundant community subset than Tomahawks. Proechimys sp. was the most abundant species trapped (N = 125) and Tomahawk was the most efficient type of trap to capture this species (N = 97 individuals). Neacomys spinosus and Marmosops bishopi were more trapped in Pitfalls (N = 92 and 100 individuals, respectively) than Shermans and Tomahawks. Monodelphis glirina was more trapped in Shermans and Pitfalls than Tomahawks. Species composition trapped using the three types of traps were distinct. Pitfalls captured a more distinct subset of the small mammal community than the two other live traps. We recommend the association of the three types of traps to reach a more comprehensive sampling of the community of small mammals. Thus, as stated by previous studies, we also recommend the complementary use of Shermans, Tomahawks and Pitfalls to account for a thorough sampling of the whole small mammal community in researches conducted in the tropical forests of Amazonia.


A eficácia das pesquisas ecológicas de comunidade de pequenos mamíferos depende fortemente do uso de técnicas adequadas nas capturas durante as amostragens. O principal objetivos deste estudo foi avaliar a eficiências de três tipos de armadilhas (Sherman, Tomahawk e Pitfall) para capturas de pequenos mamíferos não-voadores. Nós instalamos armadilhas em 22 fragmentos de floresta no sul da Amazonia Brasileira. Nós capturamos 873 indivíduos de 21 espécies, a maior parte dos indivíduos (N=369) e espécies (N=19) foram capturados usando pitfalls, seguidos de Shermans (N=271 indivíduos, N=15 espécies) e Tomahawks (N=233 indivíduos, N= 15 espécies). Pitfalls capturou a maior riqueza da comunidade de pequenos mamíferos quando comparada aos outros dois tipos de armadilhas, e uma maior abundancia que Tomahawk. Proechimys sp. foi a espécies mais abundante capturada (N=125) e Tomahawk foi o tipo de armadilha mais eficiente para a captura desta espécie (N=97 indivíduos). Neacomys spinosus e Marmosops bishopi foram mais capturados em Pitfalls (N = 92 e 100 indivíduos, respectivamente) que Shermans e Tomahawks. Monodelphis glirina foram mais capturados em Shermans e Pitfalls que Tomahawks. A composição de espécies capturada usando os três tipos de armadilhas foi distinta. Pitfalls capturou um diferente subgrupo da comunidade de pequenos mamíferos quando comparado aos outros dois tipos de live traps. Assim, como sugerido em estudos anteriores, nós também recomendamos o uso conjugado de Sherman, Tomahawks e Pitfalls para uma amostragem mais completa da comunidade de pequenos mamíferos em pesquisas realizadas nas florestas tropicais da Amazônia.


Assuntos
Animais , Biodiversidade , Caça/métodos , Mamíferos , Métodos , Biota
16.
Biota neotrop. (Online, Ed. port.) ; 13(2): 70-75, Apr-Jun/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-682392

RESUMO

The Brazilian Pantanal comprises a mosaic of forest and field environments harbouring a rich community of large and midsized mammals that are adapted to the annual hydrological cycle. Here we evaluated richness and composition of large and midsized mammals inhabiting forested and open habitats affected by yearly floods in the Pantanal in Cáceres from October 2009 to September 2010. We compared these communities in marshes, dry forests and riparian forests based on 640 camera-traps.nights, sights, tracks, faecal samples and interviews. We also compared results in a private land (Descalvados Farm) and in a protected area (Taiamã Ecological Station). In total, we sampled 26 large and midsized mammals, including five threatened and two near threatened species. Jaguars, collared peccaries and red-brocket deers were the only mammals recorded at all habitat types, while eleven species were recorded exclusively in one of the habitats. We identified a heterogeneous use of the habitat by the animal community surveyed in all three habitats during the wet and dry season. Furthermore, precipitation and river level affected the use of dry forests and marshes isolated from dry forests. Finally, 62% of large/midsized mammal species present in the surveyed region recorded outside the reserve; therefore, we recommend conservation actions to protect those species and also to preserve unprotected dry forests.


O Pantanal brasileiro é formado por um mosaico de ambientes florestados e campestres, abrigando uma rica comunidade de mamíferos de médio e grande porte adaptados ao ciclo hidrológico anual. Nós avaliamos a riqueza e composição de mamíferos de médio e grande porte em habitats florestados e campestres afetados pelas inundações anuais no Pantanal de Cáceres ente outubro/2009 e setembro/2010. Comparamos as comunidades em Campos Inundáveis, Matas Secas e Matas Ripárias com base em 640 armadilhas-fotográficas.noite, avistamentos, pegadas, amostras fecais e entrevistas. Nós também comparamos os resultados em uma área privada (Fazenda Descalvados) e em uma área protegida (Estação Ecológica Taiamã). No total, foram registradas 26 espécies de mamíferos de médio e grande porte, incluindo cinco espécies ameaçadas de extinção e duas quase ameaçadas. Onças-pintadas, catetos e veados-mateiro foram os únicos mamíferos registrados em todos os habitats, enquanto que 11 espécies foram registradas em apenas um tipo de hábitat. Identificamos diferença quanto ao uso dos habitats entre os três tipos de habitats durante a estação seca e chuvosa. Além disso, a precipitação e o nível do rio afetaram o uso da Mata Seca e Campos Inundáveis isolados das Matas Secas. Por fim, 62% das espécies foram registradas fora da reserva, por isso, recomendamos ações de conservação para proteger as espécies e também para preservar as florestas secas desprotegidas.

17.
Ciênc. rural ; 41(1): 101-107, 2011. ilus, tab
Artigo em Português | LILACS | ID: lil-571454

RESUMO

Este estudo objetivou caracterizar plantas e frutos de araticum (Annona crassiflora), avaliar a frequência de consumo, predação e dispersão de suas sementes por animais e seus efeitos na germinação, em área de Cerrado, entre fevereiro de 2007 a junho de 2008. Baseado em armadilhas de pegadas, registrou-se a frequência de visitação (FV) e o consumo de frutos por animais, além da ação de insetos em frutos caídos no solo, sob as plantas. Estrumes de antas, Tapirus terrestris, foram amostrados para verificar a frequência de ocorrência (FO) e os danos causados por elas e por insetos. Para analisar a dispersão por antas, foram inseridas miçangas coloridas em frutos maduros caídos sob plantas-mãe. Posteriormente, foi medida a distância entre o local das fezes com miçanga até a planta-mãe da cor específica da miçanga. Realizou-se teste de germinação com sementes de amostras fecais e de frutos intactos. Dentre os animais que se alimentaram dos frutos, antas contribuíram com maior frequência de visitação e consumo de frutos de araticum, o qual representou 54 por cento de frequência de ocorrência nas amostras fecais e as sementes não foram significativamente danificadas. Besouros (Scarabaeidae) se alimentaram da polpa de frutos e enterraram sementes de araticum próximo da planta-mãe. Insetos curculionídeos e euritomídeos predaram as sementes de araticum nos frutos. Os danos causados nas sementes por esses insetos foram significativamente maiores que aqueles provocados pelas antas. Foram encontradas duas fezes com miçangas distantes 1,7km e 1,8km das plantas-mãe, respectivamente. A germinação das sementes foi baixa neste período de estudo, no entanto, as antas podem proteger as sementes de insetos predadores, defecando-as intactas para longas distâncias. Assim, T. terrestris é um possível dispersor, enquanto que curculionídeos e euritomídeos são possíveis predadores de sementes de araticum. Essas relações provavelmente contribuem para o controle da população de araticum no Cerrado brasileiro.


This study aimed to characterize araticum (Annona crassiflora) plants and fruits, and evaluate the frequency of consumption, predation and dispersal of the seeds by animals and its effect on germination, in Cerrado vegetation area, between February 2007 and June 2008. Using track traps installed on araticum plants, the frequency of visitation (FV) and the fruit consumption by the animals was assessed, as well as, the action of insects in fallen fruits under the trees was registered. Sample of tapirs excrement Tapirus terrestris were analyzed to verify the occurrence frequency (FO) and the damage caused on the seeds by tapirs and insects. To analyze the dispersal by tapirs, colored beads were inserted in fallen mature fruits under the parent trees. Then, the distance between the location of the excrements with beads to the parent tree in the specific color of the bead was measured. Germination test was performed with excrement samples and unbroken fruit seeds. Among the animals that fed on fruits, tapirs contributed with the largest frequency of visitation and consumption of araticum fruits, representing 54 percent of the frequency occurrence in excrement samples, and the seeds were not damaged significantly. Dung beetles (Scarabaeidae) fed the pulp of the fruit and buried araticum seeds next to the parent tree. Curculionid and eurytomid insects predated the araticum seeds on the fruits. The damage caused by these insects in the seeds was significantly higher than those caused by tapirs. Two excrements with beads were found at 1,7 and 1,8km distant from the parent trees, respectively. The seeds had low germinability in this period of study, however the tapirs can protect the seeds of predator insects, defecating the intact seeds for long distances. Thus, T. terrestris is a possible disperser of seeds, whereas curculionids and eurytomids can be considered predators of araticum seeds. These relations probably contribute with the control of araticum population in the Brazilian Cerrado.

18.
Biota neotrop. (Online, Ed. port.) ; 8(1): 115-121, jan.-mar. 2008. graf, tab
Artigo em Português | LILACS | ID: lil-488473

RESUMO

Nós capturamos pequenos mamíferos em oito fragmentos florestais (43 a 1.411 ha) nos períodos seco e chuvoso, no sudoeste de Mato Grosso, Brasil, e investigamos a variação na riqueza e na abundância de pequenos mamíferos e em variáveis relacionadas à estrutura da floresta (volume da liteira e abertura do dossel) e à disponibilidade de artrópodes, entre os dois períodos do ano. As amostragens foram realizadas durante o período chuvoso entre 2002 e 2003 e durante período seco de 2003. Em cada fragmento, foram utilizadas armadilhas Sherman, Tomahawk, Snap trap e Pitfall durante 10 dias consecutivos em cada época do ano, totalizando 17.600 armadilhas x noites. Foram obtidas no total 379 capturas de 20 espécies, sendo sete de marsupiais e 13 de roedores, com sucesso de captura de 2,2 por cento (1,6 por cento para o período chuvoso e 2,7 por cento para o período seco). Não houve diferenças significativas na riqueza total, riqueza de roedores, riqueza de marsupiais, abundância total e abundância de roedores entre os períodos seco e chuvoso. Já a abundância de marsupiais foi significativamente maior na época da seca, quando a quantidade de chuvas é menor. O volume da liteira foi significativamente maior durante a seca, enquanto a disponibilidade de artrópodes foi significativamente maior durante o período chuvoso. Sendo assim, a grande disponibilidade de alimento no ambiente durante a estação chuvosa pode ter tornado as iscas das armadilhas menos atrativas. De maneira geral, as variações entre períodos seco e chuvoso observados estão de acordo com padrões descritos em outros estudos.


We captured small mammals in eight forest fragments (43 a 1.411 ha.) during the dry and wet seasons, in southwest Mato Grosso, Brazil, and investigated the variation in small mammal richness and abundance, as well as in forest structure variables (litter volume and canopy openness) and arthropod availability, between the two seasons. Sampling was carried out during the wet season between 2002 and 2003 and in the dry season of 2003. In each fragment, we used Sherman, Tomahawk, snap, and pitfall traps during 10 consecutive days per season, totaling 17,600 trap x nights. In total, we obtained 379 captures of 20 species, seven of marsupials and 13 of rodents. Overall capture success was 2.2 percent (1.6 percent during the wet season and 2.7 percent during the dry season). Total richness, richness of rodents, richness of marsupials, total abundance and abundance of rodents did not varied significantly between seasons. However, marsupial abundance was significantly lower in the dry season, when rainfall is high. Litter volume was significantly higher during the dry season, while arthropod availability was significantly higher during the wet season. Therefore, higher food availability during the wet season may have made trap baits less attractive. In general, the observed variations between dry and wet seasons are in accordance with patterns described in other studies.


Assuntos
Artrópodes , Mudança Climática , Efeitos do Clima , Ecossistema/análise , Mamíferos/classificação , Estações do Ano
19.
Rev. med. (Säo Paulo) ; 85(1): 11-15, 2006. tab
Artigo em Português | LILACS | ID: lil-431014

RESUMO

Objetivo: identificar com qual frequência diferentes métodos são responsáveis pelo diagnóstico inicial dos aneurismas de aorta abdominal (AAA) operados em nossa instituição no período de 2000 a 2002. Materias e métodos: foram estudados retrospectivamente, através da análise de prontuários, 200 pacientes consecutivamente submetidos à correção de AAA no períodode de dois anos. Resultados: oitenta e seis (43 por cento) pacientes tiveram o AAA clinicamente detectados, 113 (56,5 por cento) através de exames de imagem e um (0,5 por cento) durante laparotomia / Objectives: to identify the initial diagnostic method of abdominal aortic aneurysms (AAA)in patients submitted to surgeries from 2000 to 2002. Material and methods: there were analyzed 200 consective patients with an AAA submitted to resection and revascularization. Results: eight-six (43 per cent) were diagnosed clinically, 113 (56,5 per cent) during an imaging investigation...


Assuntos
Humanos , Masculino , Adolescente , Adulto , Pessoa de Meia-Idade , Aneurisma da Aorta Abdominal/diagnóstico , Diagnóstico por Imagem , Aneurisma da Aorta Abdominal/epidemiologia , Fatores de Risco , Tomografia Computadorizada por Raios X
20.
J. vasc. bras ; 4(2): 137-142, jun. 2005. tab
Artigo em Português | LILACS | ID: lil-466298

RESUMO

Objetivo: A claudicação intermitente é uma das manifestações iniciais da doença arterial obstrutiva periférica. Embora a maioria dos pacientes apresente melhora dos sintomas quando submetidos ao tratamento clínico, alguns não melhoram e podem até apresentar piora. O objetivo deste estudo é verificar se existe diferença no resultado do tratamento clínico de acordo com a localização da obstrução arterial. Métodos: Estudamos 212 pacientes portadores de claudicação intermitente por doença arterial obstrutiva periférica, que foram submetidos a tratamento clínico adequadamente realizado. Dividimos os pacientes em dois grupos: grupo AO (obstrução da aorta) e grupo FP (obstrução femoropoplítea bilateral)...


Assuntos
Humanos , Masculino , Feminino , Aorta , Artéria Poplítea/anormalidades , Claudicação Intermitente/complicações , Claudicação Intermitente/terapia , Diabetes Mellitus/diagnóstico , Hipertensão/complicações , Hipertensão/diagnóstico
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