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The impact of livestock grazing on native wildlife remains a topic for considerable debate. In the Brazilian Pantanal extensive cattle ranching has been practised since the mid-18th century and cattle live alongside a diverse group of medium to large sized terrestrial mammalian herbivores. This study examined the use, similarity and selection of forage resources among cattle ( Bos indicus ), pampas deer ( Ozotoceros bezoarticus ) and capybara ( Hydrochoerus hydrochaeris ) in a paddock in the central region of the Brazilian Pantanal. Plants consumed were identified through micro-histological analysis of faecal samples collected from three species over several seasons, and quadrats (0.5 m × 0.5 m) were allocated to patches within each of the main landscapes to measure availability of resources. Overall, cattle were classified as grazers, capybara as mixed feeders, pampas deer as browsers. 126 plants were identified in faecal samples of the three species. Similarity indices were highest between domestic cattle and the capybara and lowest between these two species and the deer. Diets were more similar between the species during the wet season (period of resource abundance) than during the dry season (period of resource scarcity). Overall animals selected different forage species H. amplexicaulis and L. hexandra were the only plants selected by all three herbivores. In this study, the presence of cattle does not appear to be as detrimental to wild herbivores as suggested by other examples in the literature. more...

departamento de Ciencias do Ambiente, Campus de Corumba, Universidade Federal de Mato Grosso do Sul, Avenida Rio Branco, no. 1270, CEP 79304-902, Caixa Postal 252, Corumba, MS, Brazil 2Departamento de Botânica, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CEP 21941-490, Rio de Janeiro, RJ, Brazil 3Departamento de Biologia, Centro de Ciencias Biologicas e da Saude, Universidade Federal de Mato Grosso do Sul, Caixa Postal 549, CEP 79070900, Campo Grande, MS, Brazil *Corresponding author; e-mail: iedamaria@terra.com.br more...

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:40:54Z No. of bitstreams: 1 S1516-89132008000100014.pdf: 1356545 bytes, checksum: 348e6f96bedb84aa99ada9c5bece6d85 (MD5) Made available in DSpace on 2013-08-22T18:40:54Z (GMT). No. of bitstreams: 1 S1516-89132008000100014.pdf: 1356545 bytes, checksum: 348e6f96bedb84aa99ada9c5bece6d85 (MD5) Previous issue date: 2008-02-01 Made available in DSpace on 2013-09-30T19:27:06Z (GMT). No. of bitstreams: 2 S1516-89132008000100014.pdf: 1356545 bytes, checksum: 348e6f96bedb84aa99ada9c5bece6d85 (MD5) S1516-89132008000100014.pdf.txt: 22058 bytes, checksum: 7cbdb47a32440b24eafd8fd52a4e6106 (MD5) Previous issue date: 2008-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:48:33Z No. of bitstreams: 2 S1516-89132008000100014.pdf: 1356545 bytes, checksum: 348e6f96bedb84aa99ada9c5bece6d85 (MD5) S1516-89132008000100014.pdf.txt: 22058 bytes, checksum: 7cbdb47a32440b24eafd8fd52a4e6106 (MD5) Made available in DSpace on 2014-05-20T13:48:33Z (GMT). No. of bitstreams: 2 S1516-89132008000100014.pdf: 1356545 bytes, checksum: 348e6f96bedb84aa99ada9c5bece6d85 (MD5) S1516-89132008000100014.pdf.txt: 22058 bytes, checksum: 7cbdb47a32440b24eafd8fd52a4e6106 (MD5) Previous issue date: 2008-02-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Este trabalho relata as características anatômicas e ultra-estruturais das células buliformes em Loudetiopsis chrysothrix (Nees) Conert e Tristachya leiostachya Nees. Ambas as espécies apresentam enrolamento foliar em condições de estresse hídrico. As principais características observadas nessas células foram: paredes periclinais mais delgadas que as epidérmicas adjacentes; abundância de substâncias pécticas na camada cuticular; paredes anticlinais sinuosas com plasmodesmas ramificados; vacuoma formado por um vacúolo desenvolvido ou inúmeros vacúolos pequenos; abundância de substâncias fenólicas e gotas de óleo dispersas. As características observadas sugerem o envolvimento das células buliformes no mecanismo de involução foliar nas espécies estudadas. This work reports anatomic and ultrastructural characteristics of bulliform cells in Loudetiopsis chrysothrix (Nees) Conert and Tristachya leiostachya Nees. Both the species presented leaf rolling under water stress. The main characteristics observed in these cells were: periclinal wall thinner than the adjacent epidermal wall; abundance of pectic substances in cuticular layer; sinuous anticlinal walls with ramified plasmodesmata; vacuome formed by a developed vacuole or innumerous small vacuoles; abundance of phenolic substances and oil drops. These characteristics suggested the involvement of bulliform cells in the mechanism of foliar involution in the studied species. Universidade Estadual Paulista Universidade Estadual Paulista Instituto de Biociências Departamento de Botânica Universidade Federal Rural do Rio de Janeiro Instituto de Biologia Departamento de Botânica Universidade Estadual Paulista Universidade Estadual Paulista Instituto de Biociências Departamento de Botânica more...

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:52:25Z No. of bitstreams: 1 S0100-84042005000100003.pdf: 949746 bytes, checksum: 5223475bc1c5916cb480bc926451957c (MD5) Made available in DSpace on 2013-08-22T18:52:25Z (GMT). No. of bitstreams: 1 S0100-84042005000100003.pdf: 949746 bytes, checksum: 5223475bc1c5916cb480bc926451957c (MD5) Previous issue date: 2005-03-01 Made available in DSpace on 2013-09-30T19:43:34Z (GMT). No. of bitstreams: 2 S0100-84042005000100003.pdf: 949746 bytes, checksum: 5223475bc1c5916cb480bc926451957c (MD5) S0100-84042005000100003.pdf.txt: 46255 bytes, checksum: 64ab411761ede64536004b5cd89c2d3e (MD5) Previous issue date: 2005-03-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:48:32Z No. of bitstreams: 2 S0100-84042005000100003.pdf: 949746 bytes, checksum: 5223475bc1c5916cb480bc926451957c (MD5) S0100-84042005000100003.pdf.txt: 46255 bytes, checksum: 64ab411761ede64536004b5cd89c2d3e (MD5) Made available in DSpace on 2014-05-20T13:48:32Z (GMT). No. of bitstreams: 2 S0100-84042005000100003.pdf: 949746 bytes, checksum: 5223475bc1c5916cb480bc926451957c (MD5) S0100-84042005000100003.pdf.txt: 46255 bytes, checksum: 64ab411761ede64536004b5cd89c2d3e (MD5) Previous issue date: 2005-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Loudetiopsis chrysothrix e Tristachya leiostachya são espécies de gramíneas que apresentam grande similaridade morfológica, distinguindose pelo número de estames e pelas características da arista. Entretanto, tais estruturas são caducas e, freqüentemente, estão ausentes na espigueta madura o que dificulta a identificação. Visando reconhecer caracteres úteis na delimitação dessas espécies, neste trabalho foram estudadas a anatomia e a ultra-estrutura da lâmina foliar. Os caracteres diferenciais entre as duas espécies foram: disposição dos tricomas tipo espinho na superfície adaxial da lâmina; profundidade dos sulcos na superfície adaxial; formato das saliências nos feixes de primeira ordem; tamanho, posição e o arranjo dos feixes vasculares na lâmina foliar; contorno dos vasos de metaxilema; número de células da extensão da bainha dos feixes vasculares; presença/ausência de células incolores no mesofilo; número de estratos de células do clorênquima radiado e distribuição do esclerênquima subepidérmico. em ambas as espécies, os cloroplastos do clorênquima apresentam grana e ausência de grãos-de-amido; os da bainha são agranais, com ou sem grãos-de-amido. Outras características como a presença de ceras epicuticulares, estômatos alojados em sulcos na superfície adaxial, diferenças no grau de sinuosidade das paredes das células epidérmicas e na estrutura das paredes celulares são comuns a espécies de cerrados e podem estar relacionadas com a economia de água. Loudetiopsis chrysothrix and Tristachya leiostachya are grasses species showing great morphological similarity, but differing in stamen number and awn characteristics. However, these structures are deciduous and frequently absent in the mature espikelet, which makes their identification difficult. In order to recognize useful characters for species delimitation, this paper studied the leaf blade anatomy and ultrastructure. The different characteristics between these species were: prickle hair arrangement on the leaf blade adaxial surface; furrow depth on the adaxial surface; saliency shape on the first order bundle; vascular bundle size, position, and arrangement on the leaf blade; metaxylem vessel outline; number of cells in the bundle sheath extension; presence/absence of colourless cells in the mesophyll; number of chlorenchyma radiated cell strata and distribution of the sub epidermal scherenchyma. In both species, chloroplasts of the chlorenchyma show grana and absence of starch grains; those in the sheath are agranal, with or without starch grains. Other characteristics such as presence of epicuticular waxes, stomata in furrows on the adaxial surface, differences in the sinuosity degree of the epidermal cell wall, and cell wall structure are common in cerrado species and can be related to water saving. Universidade Estadual Paulista Instituto de Biociências Departamento de Botânica Universidade Federal Rural do Rio de Janeiro Instituto de Biologia Departamento de Botânica Universidade Estadual Paulista Instituto de Biociências Departamento de Botânica more...

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:06:26Z No. of bitstreams: 1 S1516-35982002000700007.pdf: 289285 bytes, checksum: 137700de61d812cdd978c367c49f0cf0 (MD5) Made available in DSpace on 2013-08-22T19:06:26Z (GMT). No. of bitstreams: 1 S1516-35982002000700007.pdf: 289285 bytes, checksum: 137700de61d812cdd978c367c49f0cf0 (MD5) Previous issue date: 2002-07-01 Made available in DSpace on 2013-09-30T20:10:45Z (GMT). No. of bitstreams: 2 S1516-35982002000700007.pdf: 289285 bytes, checksum: 137700de61d812cdd978c367c49f0cf0 (MD5) S1516-35982002000700007.pdf.txt: 64854 bytes, checksum: dfb3b93c8d543791e7e779c0def677d4 (MD5) Previous issue date: 2002-07-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:48:33Z No. of bitstreams: 2 S1516-35982002000700007.pdf: 289285 bytes, checksum: 137700de61d812cdd978c367c49f0cf0 (MD5) S1516-35982002000700007.pdf.txt: 64854 bytes, checksum: dfb3b93c8d543791e7e779c0def677d4 (MD5) Made available in DSpace on 2014-05-20T13:48:33Z (GMT). No. of bitstreams: 2 S1516-35982002000700007.pdf: 289285 bytes, checksum: 137700de61d812cdd978c367c49f0cf0 (MD5) S1516-35982002000700007.pdf.txt: 64854 bytes, checksum: dfb3b93c8d543791e7e779c0def677d4 (MD5) Previous issue date: 2002-07-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) O estudo foi conduzido com o objetivo de identificar a composição botânica da dieta de bovinos criados extensivamente no Pantanal através da técnica microhistológica fecal, numa área característica da sub-região da Nhecolândia, Pantanal, no período de outubro/97 a setembro/99, e verificar a variação existente em função do mês, época, ano e estado fisiológico das vacas. Foram confeccionadas 726 lâminas, sendo cada lâmina uma unidade observacional. Com base na distribuição dos valores máximos de ocorrência da composição botânica de cada espécie/lâmina e nos quantis, as espécies foram classificadas em quatro grupos principais: 1- principal (máx >20%); 2- médio superior (12,3% 20.0%); 2- medium superior (12.3% more...