Knowledge of thermodynamic fluid properties, such as density and phase behavior, is important for the design, operation, and safety of several processes including drilling, extraction, transportation, and separation that are required in the petroleum. The knowledge is even more critical at extreme temperature and pressure conditions as the search for more crude oil reserves lead to harsher conditions. Currently, there is dearth of experimental data at these conditions and as such, the predictive capability of the existing modeling tools are unproven. The objective of this research is to develop a fundamental understanding of the impact of molecular architecture on fluid phase behavior at temperatures to 523 K (250 °C) and pressures to 275 MPa (40,000 psi). These high-temperature and high-pressure (HTHP) conditions are typical of operating conditions often encountered in petroleum exploration and recovery from ultra-deep wells that are encountered in the Gulf of Mexico. This PhD study focuses on the fluid phase behavior of a low molecular weight compound, two moderately high molecular weight compounds, three asymmetric binary mixtures of a light gas and a heavy hydrocarbon compound with varying molecular size. The compounds are selected to represent the family of saturated compounds found in typical crude oils. Furthermore, this study reports experimental data for two "dead" crude oil samples obtained from the Gulf of Mexico and their mixtures with methane from ambient to HTHP conditions. A variable-volume view cell coupled with a linear variable differential transformer is used to experimentally measure the high-pressure properties of these compounds and mixtures. The reported density data compare well to the limited available data in the literature with deviations that are less than 0.9%, which is the experimental uncertainty of the density data reported in this study. The phase behavior and density data obtained in this study are modeled using the Peng-Robinson (PR), the volume-translated (VT) PR, and the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) equations of state (EoS). The EoS pure component parameters, typically obtained from the open literature, are derived from fitting the particular EoS to, critical point, or to vapor pressure and saturated liquid density data, or to HTHP density data. For the density data reported here, the PREoS provided the worst predictions, while the VT-PREoS gives an improved performance as compared to the PREoS. However, the PC-SAFT EoS provided the best HTHP density predictions especially when using HTHP pure component parameters. The situation is however reversed in the modeling performance for the phase behavior data whereby the PC-SAFT EoS with HTHP parameters provided the worst vapor-liquid equilibria predictions. Better predictions are obtained with the PC-SAFT EoS when using parameters obtained from fit of the vapor pressure data and is comparable to the PREoS predictions. This reversal in performance is not surprising since the phase behavior data occur at moderately low pressures. The performance of the PC-SAFT EoS is extended to the experimental density data reported for the dead crude oil samples and their mixtures with methane. The PC-SAFT EoS with either set of pure component parameters yield similar predictions that are within 3% of the reported crude oil density data. However, when using the HTHP parameters, the PC-SAFT gives a good representation of the slope of experimental data, which is crucial in the calculation of second-derivative properties such has isothermal compressibility. The PC-SAFT EoS is also employed to model the crude oil HTHP density data for both the dead crude oils and their mixtures with methane using correlations for both the Low-P parameters and the HTHP parameters. The Low-P parameters are derived from fitting the PC-SAFT EoS to pure compound vapor pressure and saturated liquid density data, while the HTHP parameters are obtained from fitting the PC-SAFT EoS to pure compound HTHP liquid density data. Interestingly, the PC-SAFT EoS with the Low-P parameters provided better HTHP density predictions that are within 1.5% of the experimental data for the dead oils than the HTHP parameters that are within 2 to 4% of the data. Density predictions for the dead oil mixtures with methane are however comparable for both sets of parameters and are within 1% on average. However, the PC-SAFT EoS with HTHP parameters clearly provided better representation of the isothermal property, a derivative property obtained from density data, within 10% while predictions with the Low-P parameters can be as high as 37%. The successful completion of the thesis work expands the current knowledge base of fluid phase behavior at the extreme operating conditions encountered by engineers in the petroleum industries. Furthermore, the reported HTHP experimental data also provide a means to scientists and researchers for the development, improvement, and validation of equations with improved modeling performance.

The goal of this master thesis is to analyze impact of shocks in oil prices to automobile industry stock prices and returns. We decompose oil price shocks on oil supply shocks, aggregate demand shocks and oil-specific demand shocks and assess their individual impacts on these stock prices/returns. This is done using the vector autoregression (VAR) methodology which allows us to compute impulse responses, that is the reaction paths on the individual shocks. In addition to linear VARs we also employ threshold VAR models in order to capture nonlinearities in impulse responses and besides the aggregate automobile stock price index we compute these nonlinear impulse responses also for some selected individual car producers. We think that this analysis have two different uses. First, it can be beneficial to stock market investors. Second, it can be used by policymakers in countries such as Slovakia and the Czech Republic, which are relatively heavily dependent on automotive industry. 1

This thesis investigates the relationship between daily spot and futures prices for maturities of one, two, three and four months of West Texas Intermediate (WTI) crude oil. The data cover period January 1987-April 2015. Based on economic theory, the futures prices should be closely related to the spot price, which - in the case of crude oil market - this thesis analyses using wavelet-based approach. Main contributions of this thesis are findings in the field of time-frequency relationship of spot-futures prices of crude oil, where an alternative methodology - wavelet transformation - is used. The usage of this advanced method is also an additional contribution of this thesis because it allows us to rigorously study how co-movement (relationship) differs across frequencies/scales and time. In this thesis wavelet Coherence, wavelet bivariate correlation and relatively new method wavelet band spectral regression (WBLS) are used. This thesis brings 4 main findings. First, relationship between Futures and spot prices of crude oil is strong in all time-periods (frequencies/scales), which supports economic theory. Second and In contrary to the first finding, in the gasoline spot-futures market, we find that the relationship is strong mainly in higher scales (lower frequencies) while in lower scales (higher...

Master of Science / Department of Animal Sciences and Industry / Micheal J. Brouk / The study objective was to evaluate the application of supplemental rumen-protected lysine (RP Lys) to maintain milk production when reducing the crude protein levels in a lactating dairy cow diet. Twelve lactating multiparous Holstein cows, averaging 129 DIM, 50.2 kg milk yield, 3.6% fat and 2.9% true protein were randomly assigned to one of four 3x3 Latin squares. Each 14-d period had 11 d for adaptation followed by 3 d of data collection. Cows were offered one of three experimental treatment rations formulated with CPM Dairy (v3.0); Positive control (PC) — formulated to meet all nutrient requirements; Test diet (Test) — negative control diet formulated to meet nutrient requirements, except deficient in metabolizable protein (MP) (approximately 200 g/d) and first limiting in metabolizable Lys (approximately 10 g/d); and Test+RPL — same basal diet as negative control + RP-Lys to provide 14.5 g/d of MP-Lys. For Test+RPL, 45g of RP-Lys (AminoShure-L®; Balchem Corp., New Hampton, NY, containing 23.4g Lys) was top-dressed on the TMR once daily. The PC diet resulted in lower dry matter intake (P = 0.03) as compared to either the Test or Test+RPL diet. PC, Test, and Test+RPL cows averaged 42.6, 42.9, 43.6 kg/d of milk and 27.3, 28.4, 28.8 kg/d of DMI, respectively. Crude protein intake for the PC, Test, and Test+RPL diets was 4.83, 4.67, and 4.74 kg/d respectively. MUN decreased (P < 0.01) for cows on Test and Test+RPL diets as compared to PC diet (12.5, 12.5 and 14.9 mg/dL, respectively). Milk yield, milk components, milk component yields, FCM, ECM, SCM and production efficiencies (milk, ECM, SCM and FCM) did not differ (P > 0.05) among treatments. A post-study CPM Dairy evaluation using final chemical composition analyses of the feedstuffs and average production data from the animals predicted that diets supported more than 47 kg of milk and Lys was not limiting. Cows on the study produced slightly less milk, however DMI was 5-8% more than predicted by initial formulations. Formulation accuracy of the MP and Lys deficient diet may have been improved if data had been available from an initial adjustment period measuring DMI, body weight, milk yield and milk composition. It is also possible that the bioavailability of the RP Lys was not as great as thought during the diet formulation process. However, given the fact that the post-trial CPM analysis did not indicate a deficiency of Lys, it is not very likely that this impacted the results of this trial.

<p>Mass spectrometry (MS) alone or coupled with high-performance liquid chromatography (HPLC) or gas chromatography (GC) is a versatile analytical tool that is routinely employed for identification of unknown compounds in complex mixtures. MS operates by separating ionized analytes based on their mass-to-charge (<i>m/z</i>) ratios. If the analyte can be ionized without complete fragmentation, MS provides molecular weight information and, if performed at high resolution, elemental compositions for the ionized analytes. Tandem mass spectrometry (MSⁿ, n <u>></u> 2 where each MS step corresponds to an ion isolation or separation event) also provides structural information of ionized analytes. With this approach, structural information of the ionized analytes is obtained by isolating the ionized analytes of interest and subjecting them to fragmentation experiments, such as collision-activated dissociation (CAD). The ions of interest can also be isolated and allowed to react with gaseous molecules to generate product ions (ion-molecule reactions). </p> The experiments described in this dissertation focused on the development of tandem mass spectrometry methods based on CAD and/or gas-phase ion-molecule reactions for the differentiation of acyl, <i>N</i>- and <i>O</i>-glucuronide drug metabolites and for identification of primary carbamates as potentially mutagenic impurities. Further, by using a previously published method titled Distillation, Precipitation, Fractionation Mass Spectrometry (DPF MS), the chemical compositions of five crude oil samples, including heavy, medium, and light crude oils with different API gravities, were determined. Additionally, the gravimetric percentages of different compound classes found in these crude oils are reported as well as the correlations found between API gravities and the chemical compositions of crude oils.

Les perspectives énergétiques globales soulignent une demande croissante d'énergie sur les prochaines décennies. Le pétrole brut devrait représenter environ 35% de l'offre d'énergie primaire à l'horizon 2030 d'après l'AIE. Parmi les sources d'approvisionnement, les hydrocarbures "non conventionnels" devraient contribuer significativement à l'offre de produits pétroliers, puisqu'ils présentent un intérêt stratégique en termes de réserves et d'indépendance énergétique. L'objectif de cette thèse est l'étude du potentiel de développement des ressources d'hydrocarbure non conventionnelles sous différents scénarios liés au contexte économique et environnemental. Les sables asphaltiques, principalement localisés au Canada, constituent notre cas d'application. La première partie de cette thèse a mis en évidence deux phases de développement: la première, de 1980 à 2005, correspondant à l'émergence de la filière grâce à des leviers réglementaires, économiques et géographiques; la seconde, amorcée en 2005 avec la dégradation du contexte économique, pendant laquelle le développement de la filière s'est fortement ralenti. La seconde partie de cette thèse porte sur l'analyse prospective à horizon 2050. L'élaboration d'un premier modèle basé sur la programmation linéaire a permis de quantifier l'offre tendancielle sous différents scénarios déterministes de prix et de réglementations environnementales. En particulier, la décision d'investissement apparaît significativement impactée par l'introduction d'une taxe CO2. Un second modèle basé sur la programmation dynamique a permis d'évaluer l'offre prospective en présence d'incertitudes. Un impact négatif de l'incertitude et de la volatilité des prix sur la décision d'investissement a été mis en évidence, avec ou sans réglementation environnementale. Cet impact négatif est accentué lorsqu'une incertitude supplémentaire sur le cadre réglementaire environnemental est introduite. / International energy outlook emphasizes an increasing energy demand over the next decades. Crude oil should represent about 35% of primary energy supply by 2030 according to the IEA. Among supply sources, non conventional crude oil should contribute significantly to the supply of petroleum products, being strategic in terms of reserves and energy independence. This thesis aims to evaluate the development potential of non conventional crude oil using different scenarios regarding the economic and environmental context. Oil sands, essentially located in Canada, constitute our application. The first part of this thesis highlights two development phases: the first one, from 1980 to 2005, corresponding to the emergence of the oil sands sector through regulatory, economic and geographical levers; the second one, started in 2005 with the deterioration of the economic climate, during which oil sands development slowed down significantly. The second part of this thesis focuses on the prospective analysis of the horizon 2050. Firstly, the development of a supply model based on linear programming allowed us to quantify non conventional oil trend supply under deterministic price and environmental regulation scenarios. In particular, investment decision is significantly affected by the establishment of a CO2 tax. Secondly, the development of another supply model based on dynamic programming allowed us to evaluate future non conventional crude oil supply under uncertainties. A negative impact of price uncertainty and volatility on investment decision is highlighted, under or without environmental regulation. This negative impact is strengthened by the introduction of a supplementary uncertainty in environmental legal framework.

O objetivo desta pesquisa foi o desenvolvimento de métodos para: determinação simultânea de Cr/Fe/Ni/V em óleo cru; determinação simultânea de Co/Cu/Pb/Se em óleo cru, gasolina e diesel; determinação monoelementar de Si em óleo cru, gasolina e diesel; e determinação de espécies porfirínicas de Fe/Ni/V em óleo cru, utilizando ultracentrifugação e extração em ponto nuvem, por espectrometria de absorção atômica com forno de grafite e detecção simultânea (SIMAAS). Foram estudadas as condições de preparo das amostras por emulsão, empregando Triton X-100® como surfactante e hexano ou clorofórmio como solventes diluentes do óleo cru. Nas melhores condições, as emulsões foram preparadas em 6% (m v-1) de Triton X-100® com o óleo cru previamente diluído com 125 &#181;L de hexano (nos métodos para as determinações totais dos elementos) ou diluído com 400 &#181;L de clorofórmio (no método para a determinação das espécies porfirínicas). No método envolvendo a determinação simultânea total de Cr/Fe/Ni/V não foi utilizada agitação ultrassônica devido à pequena massa de óleo necessária (50 mg) para análise. Por outro lado, a agitação ultrassônica foi essencial para possibilitar a estabilização de maiores massas de óleo cru (200 mg e 400 mg) na emulsão. A estabilidade da emulsão só foi melhorada com agitação ultrassônica, antes da etapa de diluição com água. Nessa condição, foi possível obter emulsões estáveis com 200 mg ou 400 mg de óleo cru, por 30 min ou mais de 8 h, respectivamente. O programa de aquecimento do forno de grafite foi avaliado em cada caso, com e sem uso de diferentes modificadores químicos (Pd e Mg), especialmente nos métodos de determinação simultânea, em que foi necessário adotar condições de compromisso. Para a determinação monoelementar de Si foi verificado melhora nos parâmetros analíticos (sensibilidade e repetibilidade) com o uso de NbC como modificador permanente combinado com 20 &#181;g de Pd como modificador químico co-injetado. Os LODs estimados para Cr (0,07 &#181;g g-1), Fe (2,15 &#181;g g-1), Ni (1,25 &#181;g g-1), V (1,25 &#181;g g-1), Co (0,02 &#181;g g-1), Cu (0,03 &#181;g g-1), Pb (0,04 &#181;g g-1), Se (0,11 &#181;g g-1) e Si (0,16 &#181;g g-1) foram suficientemente baixos para permitir as determinações dos elementos com boas precisão e exatidão. Análises de materiais de referência forneceram resultados a um nível de confiança de 95%, quando aplicado o teste t>/i> de Student. O fracionamento de porfirinas de Fe/Ni/V foi feito em emulsão de óleo cru combinando com a extração por ponto nuvem (CPE) e ultracentrifugação. Nesse estudo, foi verificado a necessidade do uso de 0,1 mol L-1 de HCl para extração dos elementos associados a espécies organometálicas não porfirínicas. Após a ultracentrifugação da emulsão de óleo cru, os alfaltenos e material particulado foram separados e no sobrenadante permaneceram espécies inorgânicas, compostos organometálicos leves e porfirinas de Fe, Ni e V. Após CPE de outra emulsão de óleo cru permaneceram na fase aquosa espécies inorgânicas e composto organometálicos leves. As concentrações das porfirinas de Fe, Ni e V foram determinadas após a subtração dos resultados obtidos no primeiro (ultracentrifugação) e segundo (CPE) procedimentos. / The objective of this research was the methods development for: simultaneous determination of Cr/Fe/Ni/V in crude oil; simultaneous determination of Co/Cu/Pb/Se in crude oil, gasoline and diesel; determination of Si in crude oil, gasoline and diesel; and determination of porphyrin species of Fe/Ni/V in crude oil using graphite furnace atomic absorption spectrometry with simultaneous detection (SIMAAS). It was studied the conditions for the emulsion sample preparation, employing Triton X-100® as surfactant and hexane or chloroform as diluent of the crude oil. Under the best conditions, the emulsions were prepared in 6% (m v-1) of Triton X-100® with crude oil previously diluted with 125 &#181;l of hexane (in methods for total determination of elements) or diluted with 400 &#181;l of chloroform (in the method for determination of porfhyrin species). In the method for the simultaneous determination of Cr/Fe/Ni/V it was not necessary to use ultrasonic agitation due to the small mass of oil needed (50 mg) for analysis. On the other hand, ultrasonic agitation was essential to enable the stabilization of larger masses of crude oil (200 mg and 400 mg) in emulsion. The emulsion stability was improved with ultrasonic agitation, before dilution step with water. In this condition, it was possible to obtain stable emulsions with 200 mg or 400 m;g of crude oil, for 30 min or more than 8 h, respectively. The heating program of graphite furnace was evaluated in each case, with and without use of different chemical modifiers (Pd and Mg), especially in the methods for simultaneous determination, in which was necessary to adopt compromise conditions. For Si determination, was verified significant improvement in analytical parameters (sensitivity and repeatability) with the use of NbC as permanent modifier, combined with co-injected 20 &#181;g of Pd as chemical modifier. The LODs estimated for Cr (0.07 &#181;g g-1), Fe (2.15 &#181;g g-1), Ni (1.25 &#181;g g-1), V (1.25 &#181;g g-1), Co (0.03 &#181;g g-1), Cu (0.03 &#181;g g-1), Pb (0.04 &#181;g g-1), Se (0.11 &#181;g g-1) and Si (0.16 &#181;g g-1) were low enough to allow measurements of the elements with great precision and accuracy. Analysis of reference materials provided results at confidence level of 95%, when applied to the Student\'s t-test. The Porphyrin fractionation of Fe/Ni/V was done on crude oil emulsion by combining cloud point extraction (CPE) and ultracentrifugation. In this method, 0.1 mol L-1 of HCl must be used for extraction of elements associated with the organometallic species different of porfhyrins. After the ultracentrifugation of crude oil emulsion, asfalthene and particulate matter were separated and in the supernatant remained inorganic species, organometallic compounds and porphyrins of Fe, Ni and V. After CPE of another emulsion of crude oil, remained in the aqueous phase only the inorganic and organometallic compound species. The porphyrin concentrations of Fe, Ni and V were determined after the subtraction of the results obtained in the supernatant from the first (centrifugation) and second (CPE) procedures.

Thesis advisor: Christopher Baum / Thesis advisor: Fabio Ghironi / Do events in the natural gas market cause repercussions in the crude oil market? In light of the enormous impact that price movements in the two largest U.S. energy markets have on the economy, it is important to understand not just the individual markets but also how they relate to one another. On this front, the literature presents a puzzle: while economic theory suggests that the oil and gas markets are interlinked through a bi-directional causal relationship, empirical research has concluded that the oil market affects the gas market but not vice versa. The first chapter of this dissertation improves on the previous studies in two ways: by using high-frequency, intraday oil and gas futures prices and by analyzing the effect of specific news announcements from the weekly oil and gas inventory reports. The results dispel the notion of one-way causality and provide support for the theory. The reaction of the futures volatility and returns is asymmetric, although this asymmetry does not follow the "good news" vs. "bad news" pattern from stock and bond markets; the response depends on whether the shock is driven by oil or gas inventory gluts or shortages. The two-way causality holds not only for the nearby futures contract but also for contracts of longer maturities. These findings underscore the importance of analyzing financial markets in a multi-market context. The second chapter of this dissertation asks whether volatility and trading volume evolve in a unidirectional or bidirectional, contemporaneous or lagged relationship in the crude oil and natural gas futures markets. This question is important because it affects trading and government regulation but previous studies have come to conflicting conclusions. Their main shortcoming is the low frequency of data used in the analysis. This chapter improves on the previous studies in three ways: by using high-frequency, intraday oil and gas futures prices and volume, by including trading not only during the day but also during the night, and by analyzing not only the nearby futures contract but also contracts with longer maturities. For the nearby contract, Granger-causality tests show that past values of volume help explain volatility which agrees with the Sequential Information Arrival Hypothesis. Past values of volatility have explanatory power for volume only when absolute return is used as the volatility measure; when the conditional variance from GARCH models is used as the volatility measure, the causality in this direction disappears. These results change when low-frequency daily data is applied. It is also shown that the volatility-volume relationship differs for contracts with longer maturities. These findings are relevant for regulations, such as trader position limits recently adopted by the U.S. Commodity Futures Trade Commission. The third chapter of this dissertation investigates whether the production structure of firms affects international optimal portfolios, risk-sharing, and response of terms of trade (TOT) to shocks. The answer to this question would enhance our understanding of the home equity bias, yet it has not been addressed in the theoretical literature. This chapter studies the question in a two-country dynamic stochastic general equilibrium model with endogenous portfolio allocation. It shows that the optimal portfolio includes more home equity as the production structure changes from exporter-only, i.e., firms operating in their home countries and serving foreign markets by exports, to multi-national-company-extreme (MNC), i.e., firms hiring labor in both countries and producing locally in both countries. This shift occurs because changing the firms' production structure eliminates exposure to technology differences and allows the home household to accomplish the same diversification with less foreign equity. The production structure also has implications for the effect of technology shocks on the TOT. Under the exporter-only setup, a shock to technology causes a standard TOT deterioration, whereas under the MNC-extreme setup, a shock to technology leads to a TOT improvement. By producing testable predictions, this chapter underscores the need to take firms' production structure into account when analyzing international optimal portfolios, risk sharing, and response of the TOT to technology shocks. This is especially important since empirical research has generated conflicting results. / Thesis (PhD) — Boston College, 2012. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

Este trabalho visa o estudo da viabilidade da redução do uso de água no processo de dessalgação em refinarias de petróleo. Em uma primeira fase, foi necessário o estudo teórico da separação das emulsões água/óleo. Em seguida, foi desenvolvido um modelo matemático baseado nas forças atuantes nas gotas de água, o que possibilitou a determinação do tempo entre as colisões de pares de gotas e o estabelecimento do critério para que ocorra o fenômeno de coalescência. Esse modelo foi empregado em um sistema desenvolvido com base em autômatos celulares, o qual possibilitou o acompanhamento do processo micro e macroscópico, através do cálculo para o conjunto das gotas, e o acompanhamento visual até a separação da fase contínua. Os experimentos de laboratório, para os quais foi usado equipamento ótico para a medição da intensidade de luz transmitida ou espalhada pelas gotas, possibilitaram avaliar a influência da qualidade da água de mistura no tempo de separação das emulsões. Na unidade industrial, foram realizados testes que permitiram analisar o desempenho das dessalgadoras em diferentes situações operacionais. Os resultados obtidos através dos experimentos de laboratório e da simulação usando o modelo matemático desenvolvido mostraram-se compatíveis com os dados obtidos nos testes na unidade industrial. O trabalho mostrou ser possível alterar os esquemas de usos de água nas dessalgadoras, aumentando a taxa de reciclagem e possibilitando a otimização do consumo de água fresca neste processo, o que resultaria em redução substancial no consumo geral de água na refinaria. / The aim of this work is the study of the reduction of water consumption in petroleum desalting processes. The study of the attraction forces acting on the droplets was necessary to know how the emulsion water/oil is separated. A mathematical model based upon these forces was built to calculate the time between each droplets collision and to establish criteria for their coalescence. This model was applied to a system developed based on cellular automata, which allows to follow the process micro and macroscopically. Computations were carried out to the ensemble of droplets and the visual progression, from the start of droplets separation of the continuous phase to the end of the process could be visualized. Laboratory experiments, in which optical equipment was used to measure the light intensity transmitted or scattered by the droplets, allowed to evaluate the influence of the type of mixing water in the separation time of the emulsions. Tests in the industrial unity allowed evaluating the performance of the desalting units at different operating conditions. Conclusions of the laboratory experiments and the results of the mathematical model were compared with results of the industrial tests, showing coherence between them. The work shows that it is possible to simulate the effect of the operating variables and to alter schemes of water use in desalting units, increasing the water recycling rate, allowing optimization of fresh water consumption in this process and reducing the total water consumption in the refinery.

Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2018-09-28T18:11:26Z No. of bitstreams: 1 Edgard Gonçalves Malaguez.pdf: 624903 bytes, checksum: 6111134e8079c358a6202f314465611a (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2018-09-28T18:11:37Z (GMT) No. of bitstreams: 1 Edgard Gonçalves Malaguez.pdf: 624903 bytes, checksum: 6111134e8079c358a6202f314465611a (MD5) / Made available in DSpace on 2018-09-28T18:11:37Z (GMT). No. of bitstreams: 1 Edgard Gonçalves Malaguez.pdf: 624903 bytes, checksum: 6111134e8079c358a6202f314465611a (MD5) Previous issue date: 2018 / O objetivo deste estudo foi identificar os parâmetros que impactam na interface planta-animal e nutrição de bovinos em função dos diferentes níveis de intensificação da pastagem nativa do Bioma Pampa. O experimento teve início em agosto de 2015 e finalizado em maio de 2017. Porém, o processo das intensificações dos tratamentos começou em março de 2015. A área destinada para o experimento foi de aproximadamente 34 ha de pastagem natural. Foram avaliados os tratamentos: Campo nativo (CN); CN com calagem e adubação com fósforo e potássio (CNA); CNA com introdução de azevém anual (Lolium multiflorium) (40 kg ha-1 de sementes) e adubação nitrogenada correspondendo a 80 kg/ha/ano (CNAN); CNA com introdução de azevém anual e semeadura de leguminosas (CNAL). O grupo de animais foi constituído de novilhas em recria da raça Braford com peso aproximado no início do experimento de 136 kg de peso corporal. O delineamento experimental foi em blocos completamente casualizados com duas repetições de área e quatro tratamentos totalizando oito unidades experimentais (UEs). No capítulo I, os períodos utilizados para as avaliações foram realizados em dois momentos distintos; março e outubro de 2016. Foram avaliadas as estruturas do dossel, qualidade da pastagem e os aspectos nutricionais. Foi evidenciado crescentes consumo e digestibilidade em outubro, nos tratamentos CNAN e CNAL, assim como a relação do consumo de proteína degradável no rúmen com consumo da matéria orgânica digestível (CPDR: CMOD) foram mais altas para este mesmo período, que consequentemente influenciou o ganho médio diário (GMD), com maiores ganhos nos tratamentos CNAN 0,627 kg/dia e CNAL com 0,574 kg/dia. No capítulo II, as coletas foram mensalmente durante todo o experimento. A digestibilidade da matéria orgânica (DMO) consumida pelas novilhas, foi maior nos tratamentos CNAN e CNAL 0,635 e 0,641 g/kg DMO, respectivamente. Porém, durante a primavera foi obtido a melhor DMO com média 0,653 g/kg de DMO. A concentração proteína bruta na dieta (CPB), apresentou comportamento semelhante ao DMO. Foi criado dois modelos com uso de regressões múltiplas considerado a análise de stepwise. O primeiro modelo utilizando a estrutura da pastagem e a digestibilidade permitiu explicar 42 % da variabilidade para GMD. No segundo modelo com as variáveis; CPDR:CMOD, CMOD e CMS determinaram o coeficiente de 87 %. Conclui-se que, há medida que se intensifica a pastagem nativa há um impacto da qualidade do alimento e nos parâmetros nutricionais dos ruminantes, que são determinantes para estimativa do desempenho. / The objective of this study to identify the parameters that affect the plant-animal interface and the nutrition of cattle due to the different strategies of intensification of the native pasture from Pampa Biome. The experiment started in August 2015 and ended in May 2017. However, the process of intensifying treatments began in March 2015. The area destined for the experiment is approximately 34 ha of natural pasture, average. The following treatments were evaluated: native pasture (NP); NP with liming and fertilization with phosphorus and potassium (NPF); NPF with introduction of annual ryegrass (Lolium multiflorium) (40 kg ha-1 of seeds) and nitrogen fertilization corresponding to 80 kg / ha / year (NPFRN); NPF with introduction of annual ryegrass and legume sowing (NPFRL). The animals were composed of Braford breed with approximate weight at the beginning of the experiment of 136 kg of body weight. The experimental design was completely randomized blocks with two replicates and four treatments totaling eight experimental units (EUs). In Chapter I, the periods used for the evaluations were carried out at two different times; March and October 2016. Were evaluated canopy structures, pasture quality and nutritional aspects. Increasing intake and digestibility were evidenced in October, in the NPFRN and NPFRL treatments, as well as the relation of the intake of degradable protein in the rumen with intake of the digestible organic matter (RDP:DOMI) were higher for this same period, that consequently influenced the average daily gain (ADG), with higher gains in the treatments NPFRN 0.627 kg/day and NPFRL with 0,574 kg/day. In Chapter II, the collections were monthly throughout the experiment. The digestibility of organic matter (DOM) consumed by heifers was higher in treatments NPFRN and NPFRL 0.635 and 0.641 g/kg DMO, respectively. However, during the spring the higher DOM was obtained with a mean of 0.653 g/kg. The crude protein concentration in the diet (CPC) presented similar behavior to DOM. Two models were created using multiple regressions considered stepwise analysis. The first model using the pasture structure and the digestibility allowed explaining 42% of the variability for ADG. In the second model with the variables: RDP:DOMI, DOMI and DMI determined the coefficient of 87%. It was conclude that, as native pasture intensifies, there is an impact on the quality of the food and on the nutritional parameters of ruminants, which are determinant for estimating performance.