380 resultados para Bos taurus taurus


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The aim of this study was to evaluate the effects of breed and season on semen quality parameters of zebu bulls. Data (1,632 registers) of semen production from Gir (n = 4) and Nelore (n = 15) bulls were collected between October 2005 and November 2009. The ejaculates were collected twice a week during various seasons (summer, fall, winter, and spring) and evaluated for the following semen parameters: ejaculate volume, sperm concentration, sperm motility, forward progressive motility (FPM), and sperm morphology. Factor analysis was used to determine the relationship among variables. The effect of breed (Gir and Nelore) and season and their cross effect on each parameter and extracted factor were tested using ANOVA. A negative correlation (P < 0.05) was observed between FPM and proximal droplet, as well as with abnormal loose head, abnormal small head, pouch formation, abnormal mid-peace, and strongly folded tail. Gir bull sperm showed more major defects, detached acrosome, and minor FPM (P < 0.01), whereas Nelore bulls showed a higher number of sperm with normally loose head.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Given the importance of Guzera breeding programs for milk production in the tropics, the objective of this study was to compare alternative random regression models for estimation of genetic parameters and prediction of breeding values. Test-day milk yields records (TDR) were collected monthly, in a maximum of 10 measurements. The database included 20,524 records of first lactation from 2816 Guzera cows. TDR data were analyzed by random regression models (RRM) considering additive genetic, permanent environmental and residual effects as random and the effects of contemporary group (CG), calving age as a covariate (linear and quadratic effects) and mean lactation curve as fixed. The genetic additive and permanent environmental effects were modeled by RRM using Wilmink, All and Schaeffer and cubic B-spline functions as well as Legendre polynomials. Residual variances were considered as heterogeneous classes, grouped differently according to the model used. Multi-trait analysis using finite-dimensional models (FDM) for testday milk records (TDR) and a single-trait model for 305-days milk yields (default) using the restricted maximum likelihood method were also carried out as further comparisons. Through the statistical criteria adopted, the best RRM was the one that used the cubic B-spline function with five random regression coefficients for the genetic additive and permanent environmental effects. However, the models using the Ali and Schaeffer function or Legendre polynomials with second and fifth order for, respectively, the additive genetic and permanent environmental effects can be adopted, as little variation was observed in the genetic parameter estimates compared to those estimated by models using the B-spline function. Therefore, due to the lower complexity in the (co)variance estimations, the model using Legendre polynomials represented the best option for the genetic evaluation of the Guzera lactation records. An increase of 3.6% in the accuracy of the estimated breeding values was verified when using RRM. The ranks of animals were very close whatever the RRM for the data set used to predict breeding values. Considering P305, results indicated only small to medium difference in the animals' ranking based on breeding values predicted by the conventional model or by RRM. Therefore, the sum of all the RRM-predicted breeding values along the lactation period (RRM305) can be used as a selection criterion for 305-day milk production. (c) 2014 Elsevier B.V. All rights reserved.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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O câncer, manifestação originada pelo crescimento descontrolado de células, afeta milhões de indivíduos. Os macrófagos são as primeiras células a serem ativadas para participar de uma resposta imunológica propriamente dita, são células capazes de secretar mais de cem produtos biologicamente ativos, entre esses, espécies reativas de nitrogênio e citocinas que atuam no contexto da resposta imunológica e/ou inflamatória. Sabendo que compostos de paládio (II) podem apresentar potenciais atividades antitumorais, neste trabalho foram testado os compostos de fórmula geral PdI2 (tdmPz) e Pd (SCN)2 (tdmPz), quanto a atividade anti-inflamatória e antitumoral. Como droga padrão das reações realizadas foi utilizada a cisplatina. Foi determinada a ação destes compostos frente ao sistema imunológico através, de ensaios de determinação de índice de citotoxicidade mediano (IC50) pela técnica de MTT, óxido nítrico (NO) e determinação das citocinas pró-inflamatórias TNF- e IL-12. Além disso, foi determinada a atividade antitumoral dos compostos frente à célula tumoral de Ehrlich. Os resultados não mostraram produção de NO e das citocinas IL-12 e TNF- pelos macrófagos peritoneais de animais normais e animais portadores do tumor de Ehrlich na sua forma sólida. No que se referem à atividade tóxica dos compostos testados, estes mostraram efeito citotóxico sobre os macrófagos e sobre a linhagem tumoral testada. Sendo assim mesmo não havendo a produção de mediadores próinflamatórios, os compostos apresentaram uma considerável citotoxicidade frente às células tumorais de Ehrlich e macrófagos peritoneais

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This work analyses the chapter 35, book I, of the agricultural treatise Opus agriculturæ, written by Rutilius Taurus Aemilianus Palladius (V C.E.). In that chapter the author presents some recipes, called remedia, to protect the farm and the garden against weeds and weather phenomena, as blight and fogs. The magical practices are identified according to both the fundamental principles of magic (similarity, contiguity, contrariety), which rule magical thought, and some elements of magical symbology. As the author seems not to distinguish magic and science, for he brings together both kinds of recipes, the analysis of some remedia emphasizes a specific study on the materials and substances employed in those recipes and their value in Science today. This leads to the discussions of how magical thought works, what are the limits (if they actually exist) between Magic and Science and between Magic and Religion. This work covers the subjects above and it has the following pourposes: demonstrate the characteristics that authorize the remedia described by Palladius to be classified as folk magic; identify the relations between this kind of practice with more complex forms of magic, as with religion, with science; demonstrate the contribution of the folk magic in ancient Rome farming for the formulation of more apropriated criteria of evaluating magic in comparison to religious and scientific thought.

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Pós-graduação em Medicina Veterinária - FCAV

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)