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‣ Skull Modularity in Neotropical Marsupials and Monkeys: Size Variation and Evolutionary Constraint and Flexibility

SHIRAI, Leila T.; MARROIG, Gabriel
Fonte: WILEY-LISS Publicador: WILEY-LISS
Tipo: Artigo de Revista Científica
Português
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An organism is built through a series of contingent factors, yet it is determined by historical, physical, and developmental constraints. A constraint should not be understood as an absolute obstacle to evolution, as it may also generate new possibilities for evolutionary change. Modularity is, in this context, an important way of organizing biological information and has been recognized as a central concept in evolutionary biology bridging on developmental, genetics, morphological, biochemical, and physiological studies. In this article, we explore how modularity affects the evolution of a complex system in two mammalian lineages by analyzing correlation, variance/covariance, and residual matrices (without size variation). We use the multivariate response to selection equation to simulate the behavior of Eutheria and Metharia skulls in terms of their evolutionary flexibility and constraints. We relate these results to classical approaches based on morphological integration tests based on functional/developmental hypotheses. Eutherians (Neotropical primates) showed smaller magnitudes of integration compared with Metatheria (didelphids) and also skull modules more clearly delimited. Didelphids showed higher magnitudes of integration and their modularity is strongly influenced by within-groups size variation to a degree that evolutionary responses are basically aligned with size variation. Primates still have a good portion of the total variation based on size; however...

‣ Diet and food selection by small mammals in an old-growth Atlantic forest of south-eastern Brazil

PINOTTI, Bruno T.; NAXARA, Laura; PARDINI, Renata
Fonte: TAYLOR & FRANCIS LTD Publicador: TAYLOR & FRANCIS LTD
Tipo: Artigo de Revista Científica
Português
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Here we describe the stomach contents of nine small mammal species (seven rodents and two didelphid marsupials) co-occurring in an old-growth Atlantic forest area. For four terrestrial rodents, we also compared the importance of arthropods in the diet and the selection of arthropod groups by comparing consumption with availability. Small mammals and arthropods were sampled in a 36-ha grid containing 25 sampling stations spaced every 150 m, and 47 stomach contents were analysed. While plant matter was the predominant item in the stomach contents of two rodents (Oligoryzomys nigripes and Rhipidomys mastacalis), four species presented arthropods as the main food item (the rodents Brucepattersonius soricinus and Oxymycterus dasytrichus, and the marsupials Monodelphis n. sp. and Marmosops incanus) and three consumed more plant matter than arthropods, but had significant amounts of both items (the rodents Delomys sublineatus, Euryoryzomys russatus and Thaptomys nigrita). Our results suggest that differences in diet, coupled with differences in habit and microhabitat preferences, are important factors allowing resource partition among species of the diverse group of co-occurring terrestrial small mammals in Atlantic forest areas. Moreover...

‣ Discrimination of millipedes by the opossum Didelphis albiventris (Marsupialia, Didelphidae)

Santori, R. T.
Fonte: Assn Advan Zoology Publicador: Assn Advan Zoology
Tipo: Artigo de Revista Científica Formato: 118-119
Português
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Millipedes are toxic preys for many vertebrates. Two individuals of the opossum species D. albiventris were videorecorded when feeding on the millipedes G. olivaceus and L. dentellus. Data were compared with feeding behavior on Tenebrio larvae. The opossums are resistant to intoxication by millipedes. Although chemical defenses of the millipedes were not effective against the opossum predation, they make them less attractive.

‣ Borrelia sp. in naturally infected Didelphis aurita (Wied, 1826) (marsupialia: didelphidae)

Abel,Isis dos Santos; Almeida Junior,Denclair Escobar de; Fonseca,Adivaldo Henrique da; Soares,Cleber Oliveira; Ishikawa,Márcia Mayumi
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2000 Português
Relevância na Pesquisa
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Fifty-six opossums (Didelphis aurita) were captured on the campus of Universidade Federal Rural do Rio de Janeiro, Seropédica county, Rio de Janeiro state, in order to investigate the occurrence of Borrelia sp among them in relation with the study of spirochaetemia and its ectoparasites. Blood tests were made through dark field and phase contrast microscopy, as well as the obtainment of blood smears. Smears were stained with Giemsa stain, which did not prove efficacy. There was no relation between results obtained through blood tests (13 opossum positive for Borreliasp.), and this technique (two positive animals). Parasitaemia studies of 37 animals kept in captivity as well as of several recaptures in which animals once negative proved to be positive days later, showed that haemoscopical studies could be used as an effective diagnosis tool. Ectoparasites from nine animals were classified; with the occurrence of nymphal Amblyomma cajennense and adult Ctenocephalides sp..

‣ Toxocara cati (Nematoda: Ascarididae) in Didelphis albiventris (Marsupialia: Didelphidae) from Brazil: a case of pseudoparasitism

Pinto,Hudson Alves; Mati,Vitor Luís Tenório; Melo,Alan Lane de
Fonte: Colégio Brasileiro de Parasitologia Veterinária Publicador: Colégio Brasileiro de Parasitologia Veterinária
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 Português
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Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.

‣ Exceptionally preserved North American Paleogene metatherians: adaptations and discovery of a major gap in the opossum fossil record

Sánchez-Villagra, Marcelo; Ladevèze, Sandrine; Horovitz, Inés; Argot, Christine; Hooker, Jeremy J; Macrini, Thomas E; Martin, Thomas; Moore-Fay, Scott; de Muizon, Christian; Schmelzle, Thomas; Asher, Robert J
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Português
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A major gap in our knowledge of the evolution of marsupial mammals concerns the Paleogene of the northern continents, a critical time and place to link the early history of metatherians in Asia and North America with the more recent diversification in South America and Australia. We studied new exceptionally well-preserved partial skeletons of the Early Oligocene fossil Herpetotherium from the White River Formation in Wyoming, which allowed us to test the relationships of this taxon and examine its adaptations. Herpetotheriidae, with a fossil record extending from the Cretaceous to the Miocene, has traditionally been allied with opossums (Didelphidae) based on fragmentary material, mainly dentitions. Analysis of the new material reveals that several aspects of the cranial and postcranial anatomy, some of which suggests a terrestrial lifestyle, distinguish Herpetotherium from opossums. We found that Herpetotherium is the sister group to the crown group Marsupialia and is not a stem didelphid. Combination of the new palaeontological data with molecular divergence estimates...

‣ Adaptive Evolution of the Venom-Targeted vWF Protein in Opossums that Eat Pitvipers

Jansa, Sharon A.; Voss, Robert S.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 22/06/2011 Português
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The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae) and pitvipers (Serpentes: Crotalinae). In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF), a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results...

‣ Turgida turgida (Nematoda: Physalopteridae) parasitic in white-bellied opossum, Didelphis albiventris (Marsupialia: Didelphidae), state of Mato Grosso do Sul, Brazil

Humberg, Roberta Martins Passos; Tavares, Luiz Eduardo Roland; Paiva, Fernando; Oshiro, Elisa Teruya; Bonamigo, Raquel de Abreu; Tasso Júnior, Norton; Oliveira, Alessandra Gutierrez de
Fonte: Pesquisa Veterinária Brasileira Publicador: Pesquisa Veterinária Brasileira
Tipo: Artigo de Revista Científica
Português
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Turgida turgida tem sido amplamente relatada parasitando espécies de Didelphis na América do Norte e América do Sul com base em microscopia óptica. No entanto, as características que diferenciam T. turgida de outras espécies de Physalopteridae, devem ser observadas utilizando microscopia eletrônica de varredura (MEV). Uma fêmea, de gambá-de-orelha-branca, Didelphis albiventris, chegou morta no Centro de Reabilitação de Animais Silvestres (CRAS) no município de Campo Grande, Estado de Mato Grosso do Sul, Brasil. Durante a necropsia, os nematóides adultos foram coletados do estômago e do intestino, identificados macroscopicamente e submetidos à MEV para a determinação específica. Este é o primeiro relato de T. turgida confirmado por MEV na região Neotropical, e o primeiro relato em uma área urbana no estado de Mato Grosso do Sul.; ABSTRACT - Turgida turgida have been largely reported parasitizing Didelphis species in North and South America based on light microscopy observation. However, the features that differentiate T. turgida from other physalopterid species should be observed using scanning electron microscopy (SEM). A female white-bellied opossum, Didelphis albiventris, arrived dead at the Centro de Reabilitação de Animais Silvestres (CRAS) in the municipality of Campo Grande...

‣ Ocorrência de Ixodes loricatus Neumann, 1899 (Acari: Ixodidae) parasitando Didelphis albiventris (Lund, 1841), (didelphimorphia: didelphidae), em Campo Grande, MS

Miziara, Soraya Rosa; Paiva, Fernando; Andreotti, Renato; Koller, Wilson Werner; Lopes, Vinicius Andrade; Pontes, Nara T.; Bitencourt, Klaudia
Fonte: Revista Brasileira de Parasitologia Veterinária Publicador: Revista Brasileira de Parasitologia Veterinária
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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Este é primeiro relato da ocorrência de Ixodes no Estado do Mato Grosso do Sul e primeiro caso identificado de Ixodes loricatus Neumann, 1899, parasitando Didelphis albiventris no município de Campo Grande, MS, Brasil.; This is first report of occurence of Ixodes in the State of Mato Grosso do Sul and first description of Ixodes loricatus Neumann, 1899, parasitizing Didelphis albiventris in Campo Grande, MS, Brazil.

‣ Home-range and space use by Didelphis albiventris (Lund 1840) (Marsupialia, Didelphidae) in Mutum Island, Paraná river, Brazil

Sanches, Vítor Quadros Altomare; Gomes, Mariuciy Menezes de Arruda; Passos, Fernando de Camargo; Graciolli, Gustavo; Ribas, Augusto Cesar de Aquino
Fonte: Biota Neotropica Publicador: Biota Neotropica
Tipo: Artigo de Revista Científica
Português
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Área de vida é a área usada por um animal em suas atividades diárias. Estudos de área de vida oferecem dados sobre os sistemas reprodutivos e comportamento territorial das espécies. Nosso objetivo foi estimar a área de vida de Didelphis albiventris (Lund 1840) na ilha Mutum, no rio Paraná, Brasil. O estudo foi realizado em 2008 de março a outubro em uma grade de 19,20 ha. Esta ilha é parte da área de proteção de ilhas e várzeas do rio Paraná e sua vegetação é composta por floresta estacional semidecidual aluvial sazonal com clima subtropical úmido. O esforço amostral foi de 3.360 armadilhas-noite resultando em 152 capturas de Didelphis albiventris (Lund 1840). Foram capturados 41 indivíduos nas 42 estações compostas por uma armadilha no solo e a dois metros de altura. A maioria dos animais foi capturada no solo, independente de idade ou sexo. Quatro fêmeas e cinco machos foram recapturados pelo menos cinco vezes e foram usados para calcular a área de vida mediante método de polígono mínimo convexo. A área de vida média estimada foi de 2,33 ha ± 2,32, similar às estimativas previamente descritas por outros métodos, sugerindo que o tamanho da grade de captura, maior que a usualmente empregada em estudos de marcação-recaptura com esta espécie...

‣ Interspecific variation of zona pellucida glycoconjugates in several species of marsupial

Chapman, J.; Wiebkin, O.; Breed, W.
Fonte: Society for Reproduction and Fertility Publicador: Society for Reproduction and Fertility
Tipo: Artigo de Revista Científica
Publicado em //2000 Português
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The zona pellucida glycoconjugate content of several marsupial species was investigated using differential lectin histochemistry. Ovaries from fat-tailed dunnarts, a southern brown bandicoot, grey short-tailed opossums, brushtail possums, ringtail possums, koalas and eastern grey kangaroos were fixed, embedded in paraffin wax, sectioned and stained with ten fluorescein isothiocyanate-conjugated lectins. Sections were also incubated with either neuraminidase or saponified, respectively, before incubation with the lectins to identify saccharide residues masked by sialic acids or O-acetyl groups on sialic acids. The zonae pellucidae surrounding the oocytes of the marsupials demonstrated interspecific variation in glycoconjugate content, with mannose-containing glycoconjugates exhibiting the greatest variation. Some of the zona pellucida glycoconjugates of all species, except those of the opossums, were masked by sialic acid with an increase in fluorescence with lectins from Arachis hypogea (PNA), and Glycine max (SBA), after desialylation. The disaccharide beta-galactose(1-4)N-acetyl-D-glucosamine appeared to be conformationally masked by O-acetyl groups of sialic acids in the zonae pellucidae of all species, with an increase in fluorescence with the lectin from Erythrina cristagalli (ECA)...

‣ Effect of cooling and cryopreservation on sperm motility and morphology of several species of marsupial

Taggart, D.; Leigh, C.; Steele, V.; Breed, W.; Temple-Smith, P.; Phelan, J.
Fonte: CSIRO Publishing Publicador: CSIRO Publishing
Tipo: Artigo de Revista Científica
Publicado em //1996 Português
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The effects of long-term cooling and freezing on sperm motility are described for six marsupial species: the fat-tailed dunnart, koala, brushtail possum, long-footed potoroo, northern brown bandicoot and ring-tailed possum. The effects of up to eight days of cooling at 4 degrees C on the motility of dunnart spermatozoa and the effect of cryopreservation on spermatozoa of the other species were determined. The cryoprotectant used was a Tris-citrate-fructose-egg yolk-glycerol diluent. The percentage and rating of sperm motility, and sperm structure, as determined by light microscopy, were investigated. Sperm motility in the fat-tailed dunnart was retained for up to six days when cooled to 4 degrees C, suggesting that sperm from this species have some degree of tolerance to cold shock. After this time, however, the percentage of motile spermatozoa and their motility rating declined. In all species except the fat-tailed dunnart, reinitiation of motility following cryopreservation occurred across a range of glycerol concentrations (4-17%). Cryoprotectant containing 6% and/or 8% glycerol resulted in little change of motility rating or of the percentage of live sperm after thawing, although there was some decline in the percentage of motile sperm. The unusual structural and motility characteristics of dunnart spermatozoa may account for the lack of success of sperm cryopreservation in this species.; D. A. Taggart...

‣ Anitserum to the egg coats of the fat-tailed dunnart (Marsuplia. Dasyuridae) cross-reacts with egg coats of other marsupial and eutherian species

Roberts, C.; Selwood, L.; Leigh, C.; Breed, W.
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //1997 Português
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We are examining the extracellular coats of the brush-tailed possum as a possible target for an immunocontraceptive vaccine for biocontrol of this pest species in New Zealand. In this study we have compared the composition of the extracellular coats of the fat-tailed and stripe-faced dunnarts, brush-tailed possum, domestic rabbit, and laboratory mouse using histochemistry, immunocytochemistry, and immunofluorescence. The histochemistry of the luminal epithelium of the oviduct and mucoid coats of the marsupials and rabbit indicated that they contain acidic glycoproteins. Immunofluorescence showed that polyclonal antiserum raised against the extracellular coats of the oocyte and early embryo of the fat-tailed dunnart, cross-reacted with the extracellular coats of the oocytes of all five species. These results suggest that there are common epitopes on the extracellular coats of oocytes and early embryos of distinctly related therian species. Further work to characterise these proteins is required to determine whether there is close homology between the oviductal glycoproteins of these species.; Claire T. Roberts, Lynne Selwood, Chris M. Leigh and William G. Breed

‣ Estudo de parasitos intestinais e sanguíneos em Didelphisspp. Capturados em área urbana e em fragmentos de mata ciliar associados à bacia do rio Capivari no município de Monte Mor, São Paulo, Brasil; Study of intestinal parasites and blood Didelphisspp. captured in urban areas and riparian forest fragments associated with Capivari river basin in the city of Monte Mor, São Paulo, Brazil

Anna Karollina Menezes Teodoro
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/08/2013 Português
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Os gambás do gênero Didelphis (Marsupialia, Didelphimorphia), são animais sinantrópicos, cuja dieta generalista os predispõe a infecções por endoparasitas. Tal fato, agravado pela presença cada vez mais frequente dos mesmos em área urbana e periurbana os torna potenciais hospedeiros e veiculadores de protozoários e helmintos. O gênero já foi descrito albergando diferentes tipos de parasitos, incluindo espécies potencialmente zoonóticas, sendo necessários novos estudos para uma melhor compreensão do mesmo e suas relações com os ciclos de vida dos parasitos. Para isso, a presente pesquisa teve por objetivo estudar os parasitos intestinais e sanguíneos em Didelphis spp. capturados em área urbana pelo Serviço de Controle de Zoonoses, de janeiro de 2010 a janeiro de 2013, e em fragmentos de mata ciliar associados à Bacia do Rio Capivari, no município de Monte Mor, São Paulo (22o56'48" latitude sul, 47o18'57" longitude oeste), de junho de 2011 a maio de 2012. Os espécimes capturados foram medidos, pesados, marcados, fotografados, avaliados clinicamente, registrados e identificados para verificar a duplicidade de capturas. Foram coletadas amostras de sangue e fezes para pesquisa de parasitos intestinais e sanguíneos...

‣ Use of the space by the opossum Didelphis aurita Wied-Newied (Mammalia, Marsupialia) in a mixed forest fragment of southern Brazil

Cáceres,Nilton Carlos
Fonte: Sociedade Brasileira de Zoologia Publicador: Sociedade Brasileira de Zoologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2003 Português
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Use of the space by the opossum Didelphis aurita Wied-Newied, 1826 (Mammalia, Marsupialia) in a mixed forest fragment of southern Brazil. The space use of the marsupial Didelphis aurita was studied in a forest fragment of southern Brazil from February 1995 to January 1996. The method used was the 'distribution utilization' in which each trap was set in 38 x 38 m quadrats. Captures of each marked individual in each point give information on its habitat use. Food availability was searched and compared to the habitat utilization and to the food consumption of opossums. Distribution patterns of captures (aggregated to random) and spatial overlap between individuals were searched. Results showed aggregated distributions of individuals, particularly females, in the fragment. Females used exclusively the fragment during the drier season. Opossums tend to not choose the sites with highest food availability to establish home ranges. Spatial overlap was usually low between forest resident and neighbouring resident females, but much lower during the breeding season (only forest resident females) in an apparently pattern of territoriality. Hence, core areas of females decreased in size during the breeding season. Males probably searched primarily for mates during the breeding season being less opportunistic than females in feeding habits...

‣ Ecología de la marmosa pálida, Thylamys pallidior (Marsupialia, Didelphidae), en el desierto de Monte Central; Ecology of the mouse opossum, Thylamys Pallidior (Marsupialia, didelphidae) in the central Monte Desert

Albanese, María Soledad
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2010 Português
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La marmosa pálida es un pequeño marsupial que habita las zonas áridas de Sudamérica y cuya distribución es la más extensa dentro del género. Su historia natural es poco conocida, siendo éste el primer estudio ecológico de un marsupial en el Monte. El objetivo de esta tesis fue analizar la ecología de una población de marmosas en un ambiente árido y con gran heterogeneidad espaciotemporal. Se abordaron cuatro aspectos: la estructuración temporal de la población, la estrategia reproductiva, el uso y selección del hábitat y los hábitos alimentarios. El estudio fue realizado en 3 hábitats diferentes de la Reserva de Ñacuñán, Mendoza, entre los años 2005-2007. El esfuerzo de trampeo fue de 27.600 noches-trampas y se obtuvieron 118 capturas. Las marmosas presentaron una marcada estacionalidad en su abundancia, donde las lluvias juegan un papel importante probablemente al limitar la disponibilidad de artrópodos, su principal fuente de alimento. Su reproducción fue coincidente con la estación más favorable del año, encontrándose evidencias de mortalidad pos-reproductiva de adultos y reemplazo anual de generaciones, lo que daría lugar a una estrategia semélpara, poco común entre vertebrados. T. pallidior mostró hábitos escansoriales usando preferentemente áreas abiertas y de baja complejidad. Los resultados apoyan además un mecanismo de segregación tanto espacial...