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131.
132.
Our hypothesis suggests an improvement in carcass and meat quality of pasture‐finished animals by introducing concentrate feed into diets. This study aimed to evaluate the effect of different levels of protein‐energy supplementation on carcass and meat characteristics of Texel lambs raised on Brachiaria pastures, and compare the results with those obtained from confined animals. Thirty 2‐month‐old intact lambs were divided into five treatments: pasture with mineral supplementation, pasture containing daily supplies of 0.8, 1.6, and 2.4% BW protein‐energy supplementation, and confinement (reference treatment). All animals were slaughtered 104 days after the beginning of the experiment. Lambs submitted to 1.6% and 2.4% BW supplementation presented similar characteristics to animals kept in confinement and were superior to animals treated with 0 or 0.8% of BW supplementation levels (p < .05). Increases of subcutaneous fat thickness were verified for 0.0, 0.8, 1.6, 2.4% BW, and confinement treatments, being respectively of 0.25, 0.74, 1.61, 1.69, and 1.98. Conversely, treatments had no influence on meat physical‐chemical characteristics, being all considered moderately soft, juicy (tender), and with mild tastes and odors. Lambs raised on Brachiaria pastures have high‐quality meat, but more protein‐energy supplementation is needed to be an alternative for the feedlots for young animals.  相似文献   
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This study aimed to investigate the effects of chitosan and whole raw soybean on nutrient intake, apparent digestibility, nitrogen utilization, microbial protein synthesis, blood metabolites, feeding behavior, ruminal fermentation, digesta kinetics, and reticular flow of nutrients of buffaloes. Four ruminally‐cannulated Murrah buffaloes (351 ± 15 kg of initial BW) were randomly assigned according to a 4 × 4 Latin square design. Treatments were arranged as 2 × 2 factorial arrangement: the first factor was whole raw soybean (WRS), and the second factor was chitosan (CHI) with or without their inclusion in diets. Intake and apparent digestibility of ether extract (p < .01; p = .04, respectively), non‐fiber carbohydrates intake (p = .03) and apparent ruminal digestibility of dry matter (p = .01) were affected by diets. An interaction effect or tendency was observed for microbial nitrogen (p = .09), concentrations, ruminal ammonia nitrogen (p = .05), total volatile fatty acid (p = .03). Association of chitosan with whole raw soybean has potential effects as a modulator of rumen fermentation; therefore, chitosan can be applied as an alternative non‐ionophore for Murrah buffaloes.  相似文献   
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The objective of this study was to establish a nutrient sufficiency range and DRIS standards of Conilon coffee grown in southern Bahia, Brazil for the pre-flowering and grain-filling stages and to perform a nutritional diagnosis of these plants using different methods. The collections were performed in 24 Conilon coffee farm fields to establish the leaf nutritional standards, and 278 samples were collected to the nutritional diagnosis. The nutritional diagnosis was performed by using the sufficiency range criterion and the DRIS method. The nutrient sufficiency range and the DRIS standards must be specific to each phenological stage of the Conilon coffee plants. The leaf concentrations of calcium (Ca), sulfur (S), and boron (B) were higher in the pre-flowering stage; and the leaf concentrations of nitrogen (N), potassium (K), copper (Cu), and zinc (Zn) were higher in the grain-filling stage.  相似文献   
137.
A three-dimensional Lagrangian random flight model was constructed for numerical simulations of maize pollen dispersion. The model simulates the paths of tracer particles which are interpreted as individual pollen grains, with particle motion determined by the mean flow and a stochastic turbulent velocity. The Lagrangian approach was chosen because it can be extended to complex flow regimes. The capacity of the model to simulate measured patterns of pollen deposition was tested by comparing simulations to measurements for a small maize canopy isolated within a large field of soybeans near Ames, Iowa, USA in August 2003. For this application, measurements from a single point meteorological observation were used to generate a surface layer wind profile over the maize canopy and surrounding soybean field. The method used to construct the wind field included development of internal boundary layers as the airflow passed from one canopy surface to another. The dispersion model produced spatial patterns of particle deposition that included the sharp near-source deposition gradient consistent with observations. The model tended to over-predict particle deposition near the source field and under-predict deposition at greater distances. Inclusion of the effect of the roughness difference between the maize canopy and the surrounding soybean canopy on the flow field was found to be essential for simulation accuracy. Agreement with observations improved considerably by including an approximation for vertical motions induced by changes in surface cover. These results indicate that the Lagrangian random flight model provides a realistic simulation of pollen dispersal from an isolated maize canopy. A more complete hydrodynamic model should be explored to better represent the influence of surface inhomogeneities on winds and turbulence.  相似文献   
138.
This paper briefly reviews different debates about approaches for paths out of poverty, considering several views, from the analysis of specific policies to more general or systemic considerations. The contribution of this paper is to present a broad outline of those debates and to serve as an illustration of the complexity of analyzing paths out of poverty. It discusses in sequence, the more microeconomic approach of evaluation of individual policies for poverty alleviation; then it moves to broader issues of growth and development strategies, and macroeconomic policies, and their links to the persistence or reduction of poverty; and finally discusses the topic of institutions, related to how policy decisions are made and enforced in societies at the previous three levels. Finally, the concluding section argues that a successful program to eliminate poverty must integrate all levels of individual policies, macroeconomic programs, development strategies and good institutions. This paper hopes to contribute to that crucial work.  相似文献   
139.
Tropical arthropod surveys generally use a combination of complementary sampling methods to increase the detection of species and individuals, and to decrease the number of singletons. However, given the high arthropod abundance and the taxonomic challenges of arthropod surveys, the combination of different sampling methods may be inefficient and may increase survey costs. Harvestmen were sampled using beating tray, nocturnal search, leaf-litter manual sorting and Winkler apparatus in 70 plots distributed in two areas in Central Amazonia. Every sampled method documented different assemblages, and only the nocturnal search method proved to be efficient in representing both harvestmen richness and composition. Given the data collected from leaf-litter manual sorting, Winkler apparatus and beating tray can be used in inventories to increase the number of species collected, but may be less useful for applied or monitoring studies. Although pooling data from three methods was effective to obtain an overview of species richness, it may not be the more efficient strategy for studies of assemblage associations with environmental variables. As each method may sample distinct assemblages that have different responses to the surrounding environment, pooling data from these different methods may obfuscate patterns of assemblage composition related to environmental factors instead of clarifying them.  相似文献   
140.
A total of 179 surface sediment samples from shallow waters have been collected in Catalonia (Northwestern Mediterranean) from 2002 to 2010 to analyze heavy metals (Al, Cd, Cu, Hg, Pb, V, and Zn) concentrations, organic matter content, and sediment size in order (i) to find baseline values, (ii) to investigate metal contamination trends, and (iii) to identify its spatial and temporal distribution. Highest metals concentrations were registered in the Barcelona metropolitan area and in the mouth of Besòs and Llobregat Rivers for Zn, Cu, Pb, and Cd. Mercury was also abundant in these areas but the highest record was found close to Tarragona. The concentrations agree with those reported in other studies performed in big river’s mouths and industrialized areas. The absence of large industrial activity and urbanization outside Barcelona and Tarragona explains the low metal contents found at the other sampling sites. Based on enrichment factor (EF), Pb was the most enriched metal. Results will provide a useful aid for sustainable marine management in Catalonia.  相似文献   
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