127 research outputs found

    Forage Intake and Nitrogen Retention in Wethers Fed Ryegrass Haylage Supplemented with Maize Silage

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    Many decision support tools have been developed to predict herbage intake with herbivore ruminants indoors (Faverdin 1992) or at grazing, both using short-term (Baumont et al. 2004) or daily scale input variables (Heard et al. 2004; Delagarde et al. 2011). However, the ingestive and digestive interactions when diets with more than one type of forage are used have not been sufficiently studied. The aim of this study was to assess the effects of maize silage supplementation to wethers receiving ryegrass haylage on OM intake, OM digestibility, microbial protein synthesis and N retention

    Herbage Intake, Methane Emissions and Animal Performance of Steers Grazing Dwarf Elephant Grass with or without Access to \u3cem\u3eArachis pintoi\u3c/em\u3e Pastures

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    The inclusion of legumes in diets based on grass has nutritional benefits due to ingestive and digestive interactions (Niderkorn and Baumont 2009). Moreover, it is speculated that tropical legumes can contribute to reducing the emission of greenhouse gases (GHG) compared to diets exclusively composed of grasses (Archimède et al. 2011). However, under grazing conditions, these advantages are not always possible to obtain. This occurs when the spatial distribution of sward grasses impose limitations on access to legumes by grazing animals (Solomon et al. 2011). This can be the case, for example, when legumes are overlapped by the leaves of a tufted tall grass, as dwarf elephant grass (Crestani et al. 2013). Considering that management strategies for increasing legumes in the diet of grazing animals should be better studied and data on enteric methane emitted by ruminants eating tropical forages are scarce, the aim of this work was to evaluate the effect of access to an exclusive area of peanuts (Arachis pintoi cv. Amarillo) for cattle grazing dwarf elephant grass (Pennisetum purpureum cv. BRS Kurumi) on herbage intake, animal performance and enteric methane emission

    Pyrosequencing-based analysis reveals a novel capsular gene cluster in a KPC-producing Klebsiella pneumoniae clinical isolate identified in Brazil

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    Background: An important virulence factor of Klebsiella pneumoniae is the production of capsular polysaccharide (CPS), a thick mucus layer that allows for evasion of the host's defense and creates a barrier against antibacterial peptides. CPS production is driven mostly by the expression of genes located in a locus called cps, and the resulting structure is used to distinguish between different serotypes (K types). in this study, we report the unique genetic organization of the cps cluster from K. pneumoniae Kp13, a clinical isolate recovered during a large outbreak of nosocomial infections that occurred in a Brazilian teaching hospital.Results: A pyrosequencing-based approach showed that the cps region of Kp13 (cps(Kp13)) is 26.4 kbp in length and contains genes common, although not universal, to other strains, such as the rm/BADC operon that codes for L-rhamnose synthesis. cpsKp13 also presents some unique features, like the inversion of the wzy gene and a unique repertoire of glycosyltransferases. in silico comparison of cps(Kp13) RFLP pattern with 102 previously published cps PCR-RFLP patterns showed that cpsKp13 is distinct from the C patterns of all other K serotypes. Furthermore, in vitro serotyping showed only a weak reaction with capsular types K9 and K34. We confirm that K9 cps shares common genes with cps(Kp13) such as the rm/BADC operon, but lacks features like uge and Kp13-specific glycosyltransferases, while K34 capsules contain three of the five sugars that potentially form the Kp13 CPS.Conclusions: We report the first description of a cps cluster from a Brazilian clinical isolate of a KPC-producing K. pneumoniae. the gathered data including K-serotyping support that Kp13's K-antigen belongs to a novel capsular serotype. the CPS of Kp13 probably includes L-rhamnose and D-galacturonate in its structure, among other residues. Because genes involved in L-rhamnose biosynthesis are absent in humans, this pathway may represent potential targets for the development of antimicrobial agents. Studying the capsular serotypes of clinical isolates is of great importance for further development of vaccines and/or novel therapeutic agents. the distribution of K-types among multidrug-resistant isolates is unknown, but our findings may encourage scientists to perform K-antigen typing of KPC-producing strains worldwide.LNCC, Rio de Janeiro, BrazilUniv Fed Rio de Janeiro, Inst Microbiol Paulo de Goes, Rio de Janeiro, BrazilUniv Estadual Londrina, Dept Patol Clin Anal Clin & Toxicol, Londrina, BrazilUniversidade Federal de São Paulo, Lab ALERTA, Div Doencas Infecciosas, São Paulo, BrazilUniversidade Federal de São Paulo, Lab ALERTA, Div Doencas Infecciosas, São Paulo, BrazilWeb of Scienc

    Evaluation of the process of reabilitation of a stretch of Riparian forest in Itapemirim river watershed - ES

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    Este estudo foi realizado em uma área de floresta ciliar em processo de recuperação mediante reabilitação.A área de estudo está localizada na sub-bacia hidrográfica do rio Itapemirim, no Município de Alegre, ES, Brasil.A ocupação e uso do solo antes da revegetação eram de pastagem com Brachiaria sp. A revegetação da áreafoi feita em 1997, com espécies autóctones e alóctones arbóreas, em arranjo de distribuição aleatório, em umaárea de 1,2 ha. Para a realização dos estudos foram feitos inventários florestais nos períodos de 2004/2005e 2005/2006, sendo medidos os indivíduos de hábito arbustivo e arbóreo com circunferência à altura do peito(CAP) > 5 cm e suas alturas totais. As espécies encontradas na área foram identificadas e classificadas de acordocom seus grupos ecológicos, síndromes de dispersão e presença silvestre, sendo calculados os parâmetros florísticos,a estrutura vertical e a dinâmica estrutural desse povoamento. O objetivo do trabalho foi avaliar o desenvolvimentodo povoamento implantado para subsidiar práticas silviculturais quanto à seleção e implantação de espécies pararevegetação de áreas de floresta ciliar degradadas, em condições semelhantes. Os resultados demonstraram quefoi implantado um povoamento florestal com grande diversidade de espécies e a estratificação em classes dealtura foi à semelhança de povoamentos heterogêneos naturais. As espécies identificadas como edificadoras darevegetação da área estudada foram: Anadenanthera colubrina, Caesalpinia leyostachia, Acacia auriculiformis,Acacia mangium, Handroanthus serratifolius, Inga edulis, Joannesia princeps, Pterogyne nitens, Enterelobiumcontortisiliquum, Tabernaemontana hystrix e Anthocephalus indicus. A distribuição em classes de tamanho dacomunidade implantada ocorre em forma de "J" reverso, havendo a predominância de indivíduos pioneiros emtodas as classes de CAP. A dinâmica da estrutura horizontal apontou que, para o sucesso, continuidade e desenvolvimentoda recuperação da área, seja monitorada a regeneração natural em relação à sua presença e à eficiência dos fatoresbióticos e abióticos que nela interferem. A não observância de indivíduos arbustivos e arbóreos regenerados naturalmente,na classe de inclusão do estudo, indica a fragilidade inicial da área rumo à sustentabilidade do sistema.The study was realized in an area of riparian forest in process by means of rehabilitation. Thestudy area is located in Rio Itapemirim, in Alegre city, Brazil. The occupation and use of the soil beforethe recovery were of pasture with Brachiaria sp. The recovery of this area was in 1997, with autochthonousand allochthonous species, in casually distribution arrangement, in an area of 1,2 ha. For this studies wasrealized forest inventories in the periods of 2004/2005 and 2005/2006, being measured the arboreal individualswith circumference at breast height (CBH) and total heights. The species found in the area were identifiedand classified in this ecological groups, dispersion syndromes and wild presence, it forms calculated thefloristic parameters, the vertical structure and the structural dynamics of this plantation. The objective ofthis work went evaluate the development of the plantation implanted to subsidize practical silviculture withrelationship to the selection and plantation of species for the revegetation of degraded areas of riparianforest, in similar conditions. The results of the studies demonstrated that a forest plantation was implantedwith great diversity of species and the bedding in height classes it went to the likeness of natural heterogeneous.The species identified as builders of the plantation of the studied area were: Anadenanthera colubrina, Caesalpinia leyostachia, Acacia auriculiformis, Acacia mangium, Handroanthus serratifolius, Inga edulis, Joannesia princeps,Pterogyne nitens, Enterelobium contortisiliquum, Tabernaemontana hystrix, and Anthocephalus indicus . Theimplanted community's distribution diametric happens in reverse J shape having the pioneer individuals'predominance in all the classes of CBH. The dynamics of the horizontal structure points that for the success,continuity and development of the recovery of the area, the natural regeneration be monitored in relationto its presence and efficiency of the biotic factors and abiotic those interfere in the same. The not tree individualsobservance in natural regeneration, in the class of inclusion of the study, indicate the initial fragility of thearea heading for sustentabilidade of the system

    Abnormal Brain Activation in Neurofibromatosis Type 1: A Link between Visual Processing and the Default Mode Network

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    Neurofibromatosis type 1 (NF1) is one of the most common single gene disorders affecting the human nervous system with a high incidence of cognitive deficits, particularly visuospatial. Nevertheless, neurophysiological alterations in low-level visual processing that could be relevant to explain the cognitive phenotype are poorly understood. Here we used functional magnetic resonance imaging (fMRI) to study early cortical visual pathways in children and adults with NF1. We employed two distinct stimulus types differing in contrast and spatial and temporal frequencies to evoke relatively different activation of the magnocellular (M) and parvocellular (P) pathways. Hemodynamic responses were investigated in retinotopically-defined regions V1, V2 and V3 and then over the acquired cortical volume. Relative to matched control subjects, patients with NF1 showed deficient activation of the low-level visual cortex to both stimulus types. Importantly, this finding was observed for children and adults with NF1, indicating that low-level visual processing deficits do not ameliorate with age. Moreover, only during M-biased stimulation patients with NF1 failed to deactivate or even activated anterior and posterior midline regions of the default mode network. The observation that the magnocellular visual pathway is impaired in NF1 in early visual processing and is specifically associated with a deficient deactivation of the default mode network may provide a neural explanation for high-order cognitive deficits present in NF1, particularly visuospatial and attentional. A link between magnocellular and default mode network processing may generalize to neuropsychiatric disorders where such deficits have been separately identified
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