102 research outputs found
A Provocation on the Possibility of Intellectual Freedom Today: Universal Declaration of Human Rights
Instalações rurais e práticas de bem-estar animal na produção de bovinos de corte em propriedades rurais do município de Dom Pedrito-RS.
O presente trabalho tem por objetivos analisar as instalações rurais e as práticas de manejo que favoreçam o bem-estar animal na produção de bovinos de corte implantadas em propriedades rurais no município de Dom Pedrito, Rio Grande do Sul. Foram coletados dados de dez propriedades com o auxílio de um formulário de Boas Práticas Agropecuárias (BPA) da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), adaptado aos propósitos do trabalho. Considerou-se, para esta análise, as características estruturais das paredes do brete, seringa, embarcadouro e estado de conservação do curral. As práticas de manejo consideradas foram relacionadas aos aspectos sanitários e de embarque dos animais. As instalações, manejo sanitário e de embarque apresentaram, respectivamente, 58%, 62% e 47% de conformidade para o favorecimento do bem-estar dos animais. Constatou-se que as instalações, mesmo antigas, podem, com alguns ajustes, atender as necessidades básicas para um bom manejo com os animais. Entretanto, as consequências de práticas de manejo inadequadas no bem-estar animal e na qualidade do produto final devem ser melhor disseminadas nas propriedades rurais
Evaluation of antioxidant activity of grapevine leaves extracts (Vitis labrusca) in liver of Wistar rats
Quantitative PCR reveals strong spatial and temporal variation of the wasting disease pathogen, Labyrinthula zosterae in northern European eelgrass (Zostera marina) beds
Seagrass beds are the foundation species of functionally important coastal ecosystems worldwide. The world’s largest losses of the widespread seagrass Zostera marina (eelgrass) have been reported as a consequence of wasting disease, an infection with the endophytic protist Labyrinthula zosterae. During one of the most extended epidemics in the marine realm, ~90% of East and Western Atlantic eelgrass beds died-off between 1932 and 1934. Today, small outbreaks continue to be reported, but the current extent of L. zosterae in European meadows is completely unknown. In this study we quantify the abundance and prevalence of the wasting disease pathogen among 19 Z. marina populations in northern European coastal waters, using quantitative PCR (QPCR) with primers targeting a species specific portion of the internally transcribed spacer (ITS1) of L. zosterae. Spatially, we found marked variation among sites with abundances varying between 0 and 126 cells mg−1 Z. marina dry weight (mean: 5.7 L. zosterae cells mg−1 Z. marina dry weight ±1.9 SE) and prevalences ranged from 0–88.9%. Temporarily, abundances varied between 0 and 271 cells mg−1 Z. marina dry weight (mean: 8.5±2.6 SE), while prevalences ranged from zero in winter and early spring to 96% in summer. Field concentrations accessed via bulk DNA extraction and subsequent QPCR correlated well with prevalence data estimated via isolation and cultivation from live plant tissue. L. zosterae was not only detectable in black lesions, a sign of Labyrinthula-induced necrosis, but also occurred in green, apparently healthy tissue. We conclude that L. zosterae infection is common (84% infected populations) in (northern) European eelgrass populations with highest abundances during the summer months. In the light of global climate change and increasing rate of marine diseases our data provide a baseline for further studies on the causes of pathogenic outbreaks of L. zosterae
Current European Labyrinthula zosterae Are Not Virulent and Modulate Seagrass (Zostera marina) Defense Gene Expression
Pro- and eukaryotic microbes associated with multi-cellular organisms are receiving increasing attention as a driving factor in ecosystems. Endophytes in plants can change host performance by altering nutrient uptake, secondary metabolite production or defense mechanisms. Recent studies detected widespread prevalence of Labyrinthula zosterae in European Zostera marina meadows, a protist that allegedly caused a massive amphi-Atlantic seagrass die-off event in the 1930's, while showing only limited virulence today. As a limiting factor for pathogenicity, we investigated genotype×genotype interactions of host and pathogen from different regions (10–100 km-scale) through reciprocal infection. Although the endophyte rapidly infected Z. marina, we found little evidence that Z. marina was negatively impacted by L. zosterae. Instead Z. marina showed enhanced leaf growth and kept endophyte abundance low. Moreover, we found almost no interaction of protist×eelgrass-origin on different parameters of L. zosterae virulence/Z. marina performance, and also no increase in mortality after experimental infection. In a target gene approach, we identified a significant down-regulation in the expression of 6/11 genes from the defense cascade of Z. marina after real-time quantitative PCR, revealing strong immune modulation of the host's defense by a potential parasite for the first time in a marine plant. Nevertheless, one gene involved in phenol synthesis was strongly up-regulated, indicating that Z. marina plants were probably able to control the level of infection. There was no change in expression in a general stress indicator gene (HSP70). Mean L. zosterae abundances decreased below 10% after 16 days of experimental runtime. We conclude that under non-stress conditions L. zosterae infection in the study region is not associated with substantial virulence
Physical properties and particle-size fractions of soil organic matter in crop-livestock integration
Matéria orgânica, infiltração e imagens tomográficas de Latossolo em recuperação sob diferentes tipos de manejo
Agregação de ume nitossolo vermelho distroférrico sob sistemas de plantio direto, preparo convencional e mata nativa
Dinâmica da agregação de um solo franco-arenoso em cinco sistemas de culturas em rotação e em sucessão
Aggregate stability as affected by short and long-term tillage systems and nutrient sources of a hapludox in southern Brazil
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