892 resultados para Uberlandia (MG) Migração
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The present study aimed to evaluate the efficacy of fipronil (1 mg/kg) against three strains of ivermectin-resistant Rhipicephalus (Boophilus) microplus (R. (B.) microplus), naturally infesting cattle from different states of Brazil. Three rural properties with a history of macrocyclic lactones ineffectiveness against the cattle tick, and low frequency use of fipronil in the herd, were selected for the study. The animals were randomized according to the mean tick counts, performed on days 3, 2 and I, into three groups with 10 animals each: T01, control (saline solution); T02, subcutaneous ivermectin (0.63 mg/kg) and T03, topical fipronil (1 mg/kg). Treatment was performed on day 0. Counts of partially engorged female ticks were performed on days 3,7 and 14 post-treatment (DPT), and then every 7 days until the 49th DPT. In all three experiments, it was possible to diagnose resistance of R. (B.) microplus to ivermectin (0.63 mg/kg). The maximum efficacy (arithmetic mean) obtained for ivermectin was 64% in experiment II. On the other hand, the formulation containing fipronil (1 mg/kg) reached high efficacy values (>= 97%) in all three experiments. The results from all experiments in this study demonstrate the high efficacy of 1 mg/kg fipronil, administered pour-on in naturally infested cattle, against strains of R. (B.) microplus that are resistant to 630 mcg/kg ivermectin. (C) 2014 Elsevier B.V. All rights reserved.
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The current study evaluated, in vivo, the clinical safety and the anthelmintic efficacy of 24% aurixazole (24 mg/kg), administered orally, in bovines. Two experiments were conducted: the first one evaluating the clinical safety of 24% aurixazole (24 mg/kg) in cattle, and a second one evaluating the anthelmintic efficacy of aurixazole (24 mg/kg) against gastrointestinal nematodes on naturally infected cattle. Based on the results of clinical safety, no alterations on clinical and haematological signs and on the biochemical values obtained in animals treated orally with aurixazole 24 mg/kg were observed. Regarding the results of reduction or efficacy, obtained by eggs per gram of faeces (EPG) counts, the formulation of aurixazole reached values superior to 99% (arithmetic means) in all post-treatment dates. In two occasions, this formulation reached maximum efficacy (100%). Comparing these results with the reduction percentages obtained by EPG counts, it is possible to verify that the values obtained by all three formulations were compatible with the efficacy results. Aurixazole reached maximum efficacy (100%) against Haemonchus placei, Cooperia spatulata and Oesophagostomum radiatum. Against Cooperia punctata, this formulation reached an efficacy index of 99.99%. Regarding aurixazole, no specific trials were conducted on the field in order to evaluate the behaviour of this molecule against helminths that are resistant to other molecules, specially isolated levamisole and disophenolat: Due to this fact, future studies will be necessary to assess the effectiveness of aurixazole against strains of nematodes that are resistant to levamisole and disophenolat, but the results of clinical safety and efficacy described in this study allow us to conclude that the aurixazole molecule, concomitantly with other measures and orally administered formulations, can be another important tool in the control of nematodes parasitizing bovines. (C) 2014 Published by Elsevier Ltd.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Agronomia (Produção Vegetal) - FCAV
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The current study assessed the deleterious effects of two formulations of fluazuron (2.5 mg/kg fluazuron and a combination of 3.0 mg/kg fluazuron + 0.5 mg/kg abamectin) on the reproductive parameters of engorged Rhipicephalus (Boophilus) micro plus females that naturally detached from experimentally infested cattle in two experiments. Based on the obtained results, it can be concluded that fluazuron (2.5 mg/ kg) showed deleterious effects only on the hatchability percentage in the period of 2-7 post-treatment days of this ectoparasite's engorged females. On the other hand, the fluazuron (3.0 mg/kg) + abamectin (0.5 mg/kg) combination presented harmful effects over reproductive parameters of this tick species. Further studies should be performed with a known tick population (reference susceptible strain) to determine the effect of these formulations on the reproductive parameters and to elucidate if this field population is fluazuron resistant. (C) 2014 Elsevier Ltd. All rights reserved.
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Potassium fertilization is very important to alfalfa crop in terms of yield, quality and persistence of forage, especially on soils naturally poor K. Thus, to assess the effects of K fertilization in alfalfa production and nutritional status, was carried out an experiment in a greenhouse using samples of a Dystrophic Oxisol medium texture (LV) (0.6 mmol(c) dm(-3) K) and a Dystrophic Ultisol sandy/medium texture (PVA) (2.2 mmol(c) dm(-3) K). A completely randomized design in a factorial arrangement 6 x 2 (six K rates and two soils) was used, with four replications. The K rates used were: 0, 25, 50, 100, 150 and 200 mg kg(-1) K. Potassium fertilization increased K content in soil and shoots. Dry matter production was increased with the K addition. However, in the PVA, this occurred only in the second cut. In LV, potassium fertilization increased N concentration in alfalfa shoots in both cuts. Plants with K concentration around 10 g kg(-1) had typical symptoms of this nutrient deficiency. The K critical levels of K in soil and shoots were 1.8 mmolc dm(-3) and 16.7 g kg(-1), respectively.
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Despite the high nutritional requirements of Tifton 85 grass, often the importance of liming and potassium fertilization for this forage has been neglected. In order to evaluate the effects of such practices on shoots dry matter and tillering of this forage, was carried out an experiment in green-house conditions, by two cuts, using samples of an Oxisol medium texture and a sandy soil. Efforts were also made to determine parameters to support recommendations for liming and potassium fertilization. Was adopted the completely randomized design with four replications in a factorial scheme 4x4x2, with four K rates (0, 60, 120 and 180 mg kg(-1) K), four pH values (original, 4.9, 5.9 and 6.4) and two soils. Potassium fertilization and liming promoted a significant increase in shoot dry matter and tillering in Tifton 85 grass, in both soils and cuts. The highest yields of shoot dry matter were associated with a base saturation of 56% and pH 5.2. The critical levels of K in soil and plant were 1.7 mmol dm(-3) and 14.0 g kg(-1), respectively.
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There are few studies for the crambe crop (Crambe abyssinica Hochst), and studies that characterize the sufficiency level of K in the soil and leaves are indispensable to support future programs potassium fertilization for this crop of fall/winter. An experiment was carried out to investigate the response of crambe to K soil. The experiment was carried out on a clayey Red Latossol under no-till in Botucatu, S (a) over tildeo Paulo State, Brazil. Treatments consisted of seven K levels in the soil, resulting from the application year (2000 to 2010), the summer crop (soybean), 0, 30, 60, 90, 120, 150 and 180 kg ha(-1) K2O. Before starting the experiment, soil samples were collected at depths of 0-20 cm and soil K contents determined by the resin and Mehlich-1 method. The sufficiency levels of K in soil and leaves were obtained considering the relative yield of 90%. When the levels of soil K extracted by resin and Mehlich-1, are above 88 and 94 mg dm(-3), respectively, equivalent to 26 g kg(-1) K in the leaves, the increase in crop yield of crambe is unlikely. These values should match the sufficiency level of crop and are sufficient to achieve relative grain yield of 90%.
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The constant search for sustainability of production systems have driven research to find alternatives to the problems arising from the intensified use such systems. In this context the present work aimed study the effects of substitution of mineral nitrogen by chicken litter in oat and corn crop in succession and the chemical characteristics of soil. The study was conducted during the period May 2009 to March 2010 in area of Oxisol. The design was of randomized block with four replications. The six treatments were obtained by a combination of different amounts of chicken litter (0, 1500, 3000, 4500, 6000 and 7500 kg ha(-1)) applied 30 days before the sowing of oats combined with the mineral nitrogen applied in coverage in corn (311.1, 257.8, 202.2, 148.9, 95.6, 42.2 kg ha(-1) of urea), for the total supply of 140 kg ha(-1) of nitrogen (N). The application of poultry litter in oat promotes increased the production of dry matter, and content and accumulation of N. The mineral nitrogen substitution by chicken litter increases the yield of corn crop. The use of poultry litter alters the chemical properties of soil, increasing the levels of organic matter, exchangeable Al and acidity potential. However lowers the pH, K, Ca, Mg, sum of bases and base saturation.
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The aim of this study was to estimate milk production and food consumption during the occurrence of heat waves in the Triangulo Mineiro and Alto Paranaiba, MG by means of bioclimatic zoning based on the Temperature and Humidity Index (THI). Therefore a history of heat wave occurrence between the years 2000-2010 was compiled. The decline in milk production (DMP) and reduced food consumption (RFC) were simulated in cities where periods of heat waves were identified. Frutal and Ituiutaba had the highest rate of heat wave occurrence per year. The DMP and RFC showed bioclimatic differences between the cities of Uberaba, Ituiutaba and Frutal. The cities with the best bioclimatic conditions were Sacramento and Patrocinio, as they presented a THI classified outside of the emergency range, with a night THI of below 76 and without heat waves. Therefore, the occurrence of heat waves can impair food intake and decrease milk production, thereby most effectively demonstrating the effects of thermal stress on dairy cows in the Triangulo Mineiro and Alto Paranaiba, MG region.
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This work presents structural studies in the northwestern portion of the Pitanga Structural High, between the towns of Ipeúna and Charqueada. The area is composed by the sedimentary rocks from Paraná Basin, represented basically by Paleozoic rocks (Itararé Group, Tatuí, Irati and Corumbataí formations) and Mesozoics rocks (Pirambóia and Botucatu formations), in association with lower Cretaceous intrusive basic rocks expressed by dikes and sills. The most important structural features are distensive faults, which put together unleveled tectonic blocks and are frequently filled by diabase dikes. In this context, the main objective of this work is the study of local structures and the recognition of the tectonic association between dropped and uplifted blocks, jointly with the caracterization of a production, migration and storage model for hydrocarbons. Through the interpretation of aerial photos, field recognitions, structural and laboratorial analysis, a normal fault with direction of N30W and a slip of 20-25 meters located south of Ipeúna was recognized this fault puts the Tatuí and Irati Formations side by side. At this place and by the SP-191 route (north of Ipeúna city), sandstones from the top of Tatuí Formation are impregnated by asfaltic material. The data interpretation shows that local fault systems with NW directions have played a determinant part in the fault blocks arrangement, placing sandstone lenses from Tatuí Formation topographically above the oil shales from Irati Formation. In addition, these systems acted as migration paths to transport and storage hydrocarbon in sanstone lenses from Tatuí Formation
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This study aimed the geological characterization at scale 1:50.000 of an area belonging to the southern sector of the Brasilia Belt, located in the western portion of the Passos Nappe, near the town of Cássia, MG. In this region, outcrops rock types belonging to Araxá Group, composed of metasediments associated with metavolcanics which form a tectonometamorphic terrain of great importance for understanding the geological evolution of southeast and midwest regions of Brazil. With the development of work was possible to group the rocks in 10 lithostratigraphic units and had been identified 3 different zones of metamorphism generated during the peak metamorphism. The structural pattern of the area shows that the main foliation has average dip 30 ° NW and mineral lineation parallel to the stretching direction with 290 °. Still, we can conf irm that this inverse gradient metamorphic rocks of the Passos Nappe, described by several authors. Also, were seen lithotypes of economic interest, some already in exploitation, such as clay and sand, and other mineral commodities, which are occurring and can be used: quartz, quartzite, garnet, kyanite, rutile and zircon.
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The aim of this research project is to analyze the spatial productive circuit and circles of cooperation of Fairtrade coffee, taking as a case of study the Associação dos Agricultores Familiares do Córrego D'antas (ASSODANTAS), Poços de Caldas - MG. The main purpose is to analyze material flows (grains, supplies, etc.) established between geographically separated stages of production (production, exchange, distribution and consumption) and the relationships between the agents in order to analyze the organization and regulation of production of Fairtrade coffee. It is understood as the insertion of the Fairtrade ASSODANTAS to permit the creation of new production lines, adding value and providing greater identity and autonomy to their small farms, when compared with traditional coffee trade commodity
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Geological researches conducted in the past few years detected, through deep drill hole data, the presence of alkaline rocks in the region of Três Fontes-MG, where the Barbacena Group rocks, the Morro do Ferro Greenstone Belt rocks and Araxá/Canastra groups‟ rocks are exposed. This paper aimed the petrographic and chemical characterization of these alkaline rock types, which have not yet been described in the literature. Based on petrographic descriptions and geochemical and Scanning Electron Microscopy analysis, it was possible to characterize the rock in question as lamprophyre, rich in carbonates, phlogopite, pyroxene, olivine, titaniferous opaque minerals and apatite concentrations that reach 7%. This occurrence corresponds to an alkaline intrusion, which caused brecciation of host rocks, possibly indicating that the material is explosive, however, in the study area there was no evidence of volcanic activity on the surface