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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
801

Plasma amino acid analysis by automatic high performance liquid chromatography.

January 1998 (has links)
by Chan, Kim Hung. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 76-89). / Abstract also in Chinese. / Chapter 1. --- INTRODUCION --- p.1 / Chapter 1.1 --- amino acid analysis by high performance liquid chromatography --- p.1 / Chapter 1.1.1 --- History and Development --- p.1 / Chapter 1.1.2 --- Separation mechanism --- p.2 / Chapter 1.1.3 --- Derivatization --- p.4 / Chapter 1.1.4 --- Dqproteinization --- p.8 / Chapter 1.1.5 --- Ion-exchange or Reversed-phase HPLC --- p.9 / Chapter 1.2 --- amino acid pattern in cancer patient --- p.11 / Chapter 1.2.1 --- Cancer cachexia --- p.11 / Chapter 1.2.2 --- Causes of cancer cachexia --- p.11 / Chapter 1.2.3 --- Cytokines --- p.12 / Chapter 1.2.4 --- Metabolic Alteration in cancer cachexia --- p.13 / Chapter 1.2.5 --- Amino Acid Studies --- p.14 / Chapter 1.3 --- methodology chosen --- p.19 / Chapter 1.4 --- patient sample chosen --- p.21 / Chapter 2. --- OBJECTIVES --- p.22 / Chapter 3. --- MATERIALS AND METHOD --- p.23 / Chapter 3.1 --- apparatus --- p.23 / Chapter 3.1.1 --- HPLC System --- p.23 / Chapter 3.1.2 --- Column --- p.23 / Chapter 3.1.3 --- Detector --- p.23 / Chapter 3.1.4 --- ChemStation --- p.24 / Chapter 3.2 --- reagents --- p.24 / Chapter 3.2.1 --- Reagent and Chemical source --- p.24 / Chapter 3.2.2 --- Mobile phase --- p.24 / Chapter 3.2.3 --- Derivatization Reagent --- p.25 / Chapter 3.2.4 --- Standard preparation --- p.26 / Chapter 3.2.5 --- Internal standard --- p.28 / Chapter 3.3 --- sample preparation --- p.28 / Chapter 3.4 --- chromatographic conditions --- p.29 / Chapter 3.4.1 --- Column Temperature --- p.29 / Chapter 3.4.2 --- Injector Program --- p.29 / Chapter 3.4.3 --- Time Table for gradient elution and flow program --- p.32 / Chapter 3.5.1 --- OP A and sample Ratio and Volume --- p.32 / Chapter 3.5.2 --- Derivatization Concentration --- p.33 / Chapter 3.5.3 --- Derivatization time --- p.33 / Chapter 3 6 --- analytical performance --- p.34 / Chapter 3.6.1 --- Linearity testing --- p.34 / Chapter 3.6.2 --- Recovery studies --- p.34 / Chapter 3.6.3 --- Precision --- p.34 / Chapter 3.6.4 --- Sample storage --- p.35 / Chapter 3.7 --- clinical sample studies --- p.35 / Chapter 3.8 --- statistical analysis --- p.36 / Chapter 4 --- RESULT --- p.37 / Chapter 4.1 --- chromatographic separation --- p.37 / Chapter 4.2 --- optimization --- p.40 / Chapter 4.2.1 --- OPA and sample Ratio and Volume --- p.40 / Chapter 4.2.2 --- Derivatization time --- p.43 / Chapter 4.2.3 --- OPA Concentration --- p.43 / Chapter 4.3 --- analytical performance --- p.46 / Chapter 4.3.1 --- Linearity --- p.46 / Chapter 4.3.2 --- Recovery studies --- p.46 / Chapter 4.3.3 --- Precision Studies --- p.50 / Chapter 4.3.4 --- Sample storage studies --- p.53 / Chapter 4.4 --- clinical sample study --- p.55 / Chapter 5. --- DISCUSSION --- p.64 / Chapter 5.1 --- analytical --- p.64 / Chapter 5.2 --- clinical --- p.71 / Chapter 5.2.1 --- Normal controls --- p.71 / Chapter 5.2.2 --- Colorectal Cancer --- p.71 / Chapter 5.2.3 --- Lung Cancer --- p.72 / Chapter 5.2.4 --- Nasopharyngeal Cancer --- p.73 / Chapter 5.2.5 --- Summary --- p.74 / Chapter 6. --- CONCLUSION --- p.75 / Chapter 7. --- REFERENCES --- p.75
802

Biodisponibilidade de fontes de metionina e níveis de metionina + cistina em dietas para frangos de corte /

Prado Antayhua, Fernando Andres January 2018 (has links)
Orientador: Nilva Kazue Sakomura / Banca: Nei André Arruda Barbosa / banca: Matheus de Paula Reis / Resumo: A avaliação de fontes de metionina e níveis de metionina + cistina (Met+Cis) em dietas para frangos de corte torna-se relevante para fazer ajustes nutricionais nas fórmulas. Foram conduzidos dois experimentos com frangos de corte macho. No experimento I, foi avaliada a biodisponibilidade relativa(BDR) da metionina hidroxi análoga cálcica(Ca-MHA) em relação a DL-metionina(DL-Met) em duas fases de criação de 1 até 21 dias e 21 até 42 dias. Em ambas as fases foram utilizadas 1890 aves macho da linhagem Cobb 500 que foram alimentadas com uma dieta basal com concentrações adequadas em todos os nutrientes com exceção da Met+Cis. Em cada fase, a dieta basal foi suplementada com níveis equimolares de cada fonte de metionina. Em ambas as fases, foram mensurados o ganho de peso, consumo de ração e conversão alimentar. Na segunda fase de criação, aos 42 dias foi determinado o rendimento de carcaça e peito. Através do uso da regressão multi-exponencial foi estimada a BDR média para ambas as fases de 60 e 72% da Ca-MHA em relação à DL-Met na base produto-produto e na base equimolar, respetivamente. No experimento II, foi determinado a concentração ótima biológica e econômica de Met+Cis em dietas de frangos de corte macho em duas fases de 1 até 21 dias, e 21 até 42 dias. Desta forma foram utilizados 1050 aves da linhagem Cobb 500 para cada fase. Na primeira fase, foram avaliadas os níveis de 5.60, 6.08, 7.11, 8.65, e 10.71 g/kg de Met+Cis, em quanto que na segunda fase foram avaliados os n... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Methionine is the first limiting amino acid in poultry diets based on corn and soybean meal. Thus, the assessment of methionine sources and dietary levels of methionine plus cystine (Met+Cys) in broiler diets is important to adjust nutritional composition of broiler diets. It was conducted two experiments with male broilers. In experiment I, it was evaluated the relative bioavailability (RBA) of calcium salt of methionine hidroxi analogue(Ca-MHA) in relation to DL-methionine(DL-Met) in two broiler phases, 1 to 21 days and 21 to 42 days. In both of phases, it was used 1890 birds of Cobb 500 strain that were fed with a basal diet adequate in all nutrients with exception of Met+Cys. In each phase, the basal diet was supplemented with equimolar levels of each methionine source. In both of phases, it was measured body weight gain, feed intake and feed conversion ratio. In the second phase, at 42 days of age it was determined the carcass and breast yield of broilers. By the use of multi-exponential regression analysis it was estimated an average RBA of 60 and 72% of Ca-MHA in relation to DL-Met in a product-to-product basis and on an equimolar basis, respectively. Through the conduction of experiment II, it was determined a biological and economical concentration of Met+Cys of male broiler diets of both of phases 1 to 21 and 21 to 42 days. Thus, it was used 1050 birds of Cobb 500 strain in each phase. In the first phase, it was assessed dietary levels of 5.60, 6.08, 7.11, 8.65, and... (Complete abstract click electronic access below) / Mestre
803

Exigência de isoleucina para frangos de corte /

Melaré, Mirella Cunha. January 2018 (has links)
Orientador: Nilva Kazue Sakomura / Coorientador: Matheus de Paula Reis / Banca: Flávio Alves Longo / Banca: Gabriel da Silva Viana / Resumo: A utilização de modelos matemáticos na área de nutrição avícola está se tornando frequente entre as empresas do ramo, que manipulam essa ferramenta com o intuito de melhorar a produtividade e o lucro da atividade. Neste contexto, existe a necessidade de mais pesquisas, visando o estudo das respostas dos animais, estabelecendo valores corretos de eficiência de utilização e assim produzir modelos acurados para predição da ingestão ideal de nutrientes, como a ingestão de Isoleucina (Ile). Dessa forma, o objetivo do presente estudo foi avaliar as respostas das aves submetidas a dietas com níveis crescentes de isoleucina de modo a estimar a exigência de consumo desse aminoácido, além de determinar a eficiência de utilização e desenvolver modelos de predição da exigência de isoleucina para frangos de corte. Foram realizados seis ensaios, três para machos e três para fêmeas, utilizando 640 frangos de corte Ross 308 em cada ensaio. Avaliou-se as fases inicial (1 a 14 dias), crescimento (15 a 28 dias) e final (29 a 42 dias). No total, 8 tratamentos foram distribuídos aleatoriamente em 4 repetições de 20 aves cada. Os tratamentos consistiram em 7 níveis crescentes de Ile e um contra-prova, para confirmar que a Ile foi o primeiro aminoácido limitante na dieta. A técnica de diluição foi aplicada para produzir os níveis de Ile e manter a relação de aminoácidos com a lisina. As variáveis de resposta foram: consumo de ração (CR), ganho de peso corporal (GP) e conversão alimentar (CA). No pr... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of models in poultry nutrition is becoming decisive among companies, which uses such tool to improve their productivity and profit. In this context, there is a necessity of more research, to study the responses of birds, to elucidate the efficiency of utilization and to produce models to predict an optimal nutrient intake, such as Isoleucine (Ile) intake. The objective of this work was to evaluate the responses of birds submitted to diets with increasing levels of Ile in order to estimate the requirements of this amino acid, as well as to determine the efficiency of isoleucine utilization and to develop models of prediction of Ile requirements for broiler chickens. Six dose response trials were carried out, three for males and three for females, with 640 Ross 308 in each studied phase. The initial (1 to 14 days), grower (14 to 28 days), and finisher (28 to 42 days) phases were evaluated to cover the growing phase of the broiler chicken. In total, 8 treatments were randomly distributed to 4 replicates of 20 birds each. The treatments consisted in 7 crescent levels of Ile and one counter proof, to ensure that Ile was the first limiting amino acid in the diet. Dilution technique was applied to produce the levels of Ile and keep the amino acid ratio with lysine. The response variable where feed intake (FI), body weight gain (BWG), and feed conversion ratio (FCR). In the firs paper, three different mathematical models (linear broken line (LBL), quadratic broken line (QBL),... (Complete abstract click electronic access below) / Mestre
804

The evolution of codon usage and base composition

Perry, Richard Henry John January 2015 (has links)
This thesis aims to address issues relating to genome architecture and base composition. The first part of this thesis addresses questions relating to codon usage. Initially I will investigate thousands of bacterial species using a detailed analysis of strengths of selection acting upon codons usage while also investigating patterns of optimal codon changes with respect to genomic base composition and tRNA abundance. I report that selection on codon usage increases throughout the length of highly expressed genes, in particular, the first quarter of genes have significantly lower selection. Further, it is clear that factors affecting genomic base composition can eventually lead to changes in optimal codons if the change in base composition is strong enough, however these patterns differ substantially between amino acids. The debate over translational efficiency vs. accuracy was addressed by comparing sites of differing conservation. Differing conservation were defined using a phylogenetic method, allowing sites to change in their extent of conservation throughout the tree. The results show that translational accuracy acts strongly on the top 10% of conserved sites, however is relatively weak when compared to the efficiency for other sites. Also detected is a reduction in apparent selection on codon usage on the bottom 10% of conserved sites which is likely to be caused by conflicting positive selection on amino acids. Finally, although differences in patterns are observed between amino acids, the general relationship to conservation is similar. As much of the variation in codon usage is determined by variation in base composition, this aspect of base composition is investigated in the second part of the thesis. The observed variation in intragenomic base composition in bacteria was found to be far higher than expected for GC-rich bacteria. The non-core part of the genome contributes to this variation to a greater extent than the core part, suggesting that processes such as AT-rich horizontal gene transfer may be involved. Secondly, base composition is modelled under Brownian motion and as an extension, the Ornstein- Uhlenbeck process, which allows for multiple optima throughout the tree. The model including optima fits the data better than standard Brownian motion or Brownian motion with multiple diffusion coefficients. Finally, I investigate a case where a previous codon usage analysis has been seriously confounded by an unusual genome architecture of abnormal regional base composition in two species of eukaryotic parasites in the genus Theileria. In both species, the background G+C content is 37% at most, out of the four syntenic chromosomes. In many orthologous regions however, T.annulata has a decreased G+C content of 28% while T.parva has an increased G+C content of 41%. Various factors coincide with this remarkable divergence: increased divergence at all types of site, recombination hot spots in T.parva, an increased frequency of tandem repeats and DNA sequence motifs in both species. The evolutionary origins of these unusual patterns will be discussed.
805

Applications of iontophoresis in sports medicine

Sylvestre, Jean-Philippe January 2007 (has links)
In this thesis, two potential applications of transdermal iontophoresis in the field of sports medicine were studied: (1) the local delivery of dexamethasone phosphate (Dex-Phos), a corticosteroid used to treat musculoskeletal inflammation, and (2) the extraction of systemic amino acids (AAs), potential biological markers of fatigue in athletes. The iontophoretic delivery of Dex-Phos was studied, in vitro, in order to evaluate the effects of competing ions and electroosmosis, and identify the optimal conditions for its delivery. The iontophoretic extraction of AAs from the skin was first studied in vitro, before evaluating the method in a group of human volunteers. Dex-Phos was best delivered by iontophoresis from the cathode in absence of background electrolyte in the drug solution. In this situation, the delivery of Dex-Phos is limited principally by the competition with counter-ions (mainly Na+) present subdermally and the small mobility of the drug inside the membrane. The accumulation of Cl-, released by the Ag/AgCl cathode in the drug solution during current passage, can also reduce Dex-Phos delivery. The extraction of zwitterionic AAs from the skin during iontophoresis was highly influenced by their presence in the outermost layer of the skin, the stratum corneum (SC). In the pig skin model, the amount of the AAs extracted during a short extraction period (1 hour) correlated with their abundance in the SC. Once this ‘reservoir’ was emptied (after ~3 hours of iontophoresis), the subdermal compartment could be sampled, suggesting that the method could be used to monitor systemic levels of AAs. The experiments in human volunteers revealed, however, that a 4-hour iontophoretic extraction period was insufficient to deplete the AAs SC ‘reservoir’. It follows that the method can be used to evaluate the abundance of AAs in the SC, but is unpractical for the clinical monitoring of their systemic levels.
806

Avaliação do metabolismo proteico e aminoacídico de cães com shunt portossistêmico / Evaluation of amino acid and protein metabolism in dogs with portosystemic shunt

Mariane Ceschin Ernandes 31 August 2018 (has links)
No desvio portossistêmico, o sangue proveniente do trato gastrintestinal não é direcionado ao fígado para ser metabolizado e sim desviado para a circulação sistêmica. O acúmulo dessas substâncias tóxicas associado às alterações funcionais do órgão pode resultar em encefalopatia hepática. O manejo nutricional é o ponto chave para o sucesso da terapia. Dessa forma, o presente estudo objetivou avaliar os efeitos do emprego de um alimento hipoproteico nas concentrações séricas aminoacídicas de cães com desvio portossistêmico. Foram incluídos nove cães com diagnóstico de desvio portossistêmico (Shunt) e nove cães saudáveis (Controle). Os animais foram avaliados no dia um (T0) e após 60 dias (T60) de ingestão de uma dieta hipoproteica comercial. Nos dois momentos foram coletadas amostras de sangue para realização de hemograma, leucograma, bioquímica sérica, determinação dos aminoácidos séricos e amônia. A análise estatística dos resultados referentes aos hemogramas e exames bioquímicos foi baseada em um modelo misto que considerou efeito fixos de grupo, tempo e interação e, para os aminoácidos somente efeitos fixos de grupo (p<0,05). Os animais do grupo controle apresentaram maiores valores de proteína total (p<0,0001), ureia (p<0,0001), creatinina (p=0,0163), albumina (p<0,0001) e colesterol (p=0,0012) quando comparado ao grupo Shunt que apresentou maiores valores de hematócrito (p=0,0213), ALT e FA (p=0,0253 e p=0,0004, respectivamente), amônia em jejum (p=0,0083) e amônia pós-prandial (p=0,0036). Em relação aos aminoácidos séricos, o grupo Shunt apresentou valores maiores quando comparados ao grupo Controle nas concentrações dos aminoácidos fenilalanina (p=0,0054), glutamato (p=0,0066), serina (p=0,0054) e tirosina (p=0,0106), já o aminoácido sérico alanina (p=0,0280), a razão de Fischer (p=0,0093) e a razão da concentração sérica de aminoácidos de cadeia ramificada e tirosina (p=0,0243) foram maiores no grupo Controle. Concluiu-se que o manejo dietético foi eficiente em prevenir a progressão da doença e controlar os sinais clínicos, sem promover aumento nas concentrações séricas dos aminoácidos de cadeia ramificada. / In the portosystemic shunt, the blood coming from the gastrointestinal tract is not directed to the liver to be metabolized but rather diverted to the systemic circulation. The accumulation of these toxic substances associated with functional alterations of the organ can result in hepatic encephalopathy. Nutritional management is the key to successful therapy. Thus, the present study aimed to evaluate the effects of the use of a hypoproteic food on the protein and amino acid profile of dogs with portosystemic shunt. For this, nine dogs with a diagnosis of portosystemic shunt (Shunt) and nine healthy dogs (Control) were included. The dogs were evaluated on day one (T0) and after 60 days (T60) feeding a commercial hypoprotein diet. Blood samples were collected for hemogram, leukogram, serum biochemistry, determination of serum amino acids and ammonia. For the analysis of hemograms and biochemistry, a mixed model was used considering group fixed effects, time and interaction, and for amino acids only group fixed effects (p<0.05). The results showed that the animals in the Control group presented higher values of total protein (p<0.0001), urea (p<0.0001), creatinine (p=0.0163), albumin (p<0.0001) and cholesterol (p=0.0012) when compared to the Shunt group that presented higher values of hematocrit (p=0.0213), ALT and FA (p=0.0253 and p=0.0004, respectively), fasting ammonia (p=0.0083) and postprandial ammonia (p=0.0036). Serum amino acids (p=0.0054), glutamate (p=0.0066), serine (p=0.0054) and tyrosine (p=0.0054) were higher in the Shunt group than in the Control group (0.0106). The Fischer ratio (p=0.0093) and the ratio of serum concentration of branched-chain amino acids and tyrosine (p=0.0243) were higher for the Control group. In conclusion, that dietary management was efficient in preventing disease progression and controlling clinical signs without increasing branched-chain amino acids.
807

L-prolina no alívio do estresse térmico em tomateiro cultivado em ambiente protegido / L-proline in the relief of heat stress in tomatoes cultivated in a protected environment

Rachel Tonhati 12 November 2018 (has links)
A produção de tomate (Solanum lycopersicum L.) no estado de São Paulo é de grande importância para a produção brasileira, pois representa 21,5 % da produção total e é o principal estado produtor de tomate de mesa. O tomate de mesa é cultivado por tutoramento das plantas e o cultivo em casas de vegetação é uma prática crescente no Brasil, trazendo muitas vantagens a produção, como proteção às chuvas e pragas. Porém em muitos casos, dependendo da estrutura utilizada, pode ocorrer aumento da temperatura interna das casas de vegetação. O tomateiro é uma planta sensível as altas temperaturas, e alterações dos níveis ótimos podem causar danos no metabolismo e consequentemente na produtividade da cultura. Altas temperaturas no cultivo de tomate são prejudiciais ao seu desenvolvimento, pois alteram a homeostase celular e desregulam funções vitais das plantas, como fotossíntese, gerando em excesso espécies reativas de oxigênio (EROs) como os radicais superóxidos, peróxido de hidrogênio e radicais hidroxilas, que são tóxicos às plantas e causam estresse oxidativo, levando até a sua morte. Plantas estressadas acumulam solutos osmoprotetores, entre eles a L-prolina, que auxiliam na proteção das estruturas celulares, na eliminação das EROs e também ativam o metabolismo antioxidante das plantas. Além da acumulação endógena de L-prolina, a aplicação exógena desse aminoácido pode trazer vantagens ao alívio do estresse térmico. Esse estudo teve por objetivo avaliar a eficiência da L-prolina nas doses de 0, 50, 100, 200, 400, 800 e 1600 mg/L na nutrição foliar, parâmetros fotossintéticos, enzimas do sistema antioxidante, malonaldeído e peróxido de hidrogênio, produtividade e características pós colheita dos frutos. Os dados climáticos durante o cultivo do tomateiro evidenciaram a ocorrência de temperaturas elevadas durante o ciclo de produção. Assim, foi possível observar que a aplicação exógena de L-prolina nas doses de 50 e 100 mg/L aumentaram a eficiência do uso da água, diminuíram o conteúdo de malonaldeído e aumentaram a produtividade comercial e total de frutos por planta. O uso de 50 mg/L desse aminoácido também proporcionou aumento do número de frutos comerciais por planta. A aplicação de L-prolina, independente da dose, proporcionou diminuição no conteúdo de peróxido de hidrogênio e elevou a atividade das enzimas do sistema antioxidante, além de melhorar a qualidade do fruto, diminuindo a acidez e aumentando a relação SST/ATT. Dessa maneira, constatou-se o efeito positivo do uso exógeno da L-prolina no alívio dos danos causados por altas temperaturas, principalmente em plantas tratadas com 50 e 100 mg/L. / The production of tomato (Solanum lycopersicum L.) in the state of São Paulo is of great importance for the Brazilian production, it represents 21.5% of total production and is the main state table tomato producer. The fresh tomato is grown by staking of plants and cultivation in greenhouses is a growing practice in Brazil, bringing many benefits to production, as protection of rain and pests. However, in many cases, depending on the structure used, there may be an increase in the internal temperature of the greenhouse. The tomato is a plant sensitive to high temperatures, and changes in optimal levels can cause damage to metabolism and consequently crop productivity. High temperatures in tomato cultivation are detrimental to their development, as they alter cellular homeostasis and deregulate vital plant functions, such as photosynthesis, generating in excess reactive oxygen species (ROS) such as superoxide radicals, hydrogen peroxide and hydroxyl radicals, which are toxic to plants and cause oxidative stress, leading to their death. Stressed plants accumulate osmoprotective solutes, including proline, which help protect cell structures, eliminate ROS and also activate plant antioxidant metabolism. In addition to the accumulation of endogenous proline, exogenous application of this amino acid can bring advantages to the relief of heat stress. The objective of this study was to evaluate the efficiency of L-proline at doses of 0, 50, 100, 200, 400, 800 and 1600 mg / L by foliar spray, in photosynthetic parameters, antioxidant system enzymes, malonaldehyde and hydrogen peroxide, productivity and post-harvest characteristics of fruits. The climatic data during tomato cultivation evidenced the occurrence of high temperatures during the production cycle. Thus, it was possible to observe that the exogenous application of L-proline at doses of 50 and 100 mg / L increased the efficiency of water use, decreased malonaldehyde content and increased commercial and total fruit yield per plant. The use of 50 mg / L of this amino acid also provided an increase in the number of commercial fruits per plant. The application of L-proline, regardless of the dose, resulted in a decrease in the hydrogen peroxide content and increased the activity of the antioxidant system enzymes, besides improving fruit quality, decreasing the acidity and increasing the SST/ATT ratio. Thus, there was the positive effect of the exogenous use of L-proline in alleviating the damage caused by high temperatures, especially in plants treated with 50 and 100 mg / L.
808

Suplementação de um complexo enzimático de carboidrases em dietas milho-soja para frangos de corte / Supplementation of a carbohydrases enzymatic complex in corn-soy based diets for broiler chickens

Rios, Heitor Vieira January 2017 (has links)
Objetivou-se avaliar o efeito da suplementação de um complexo enzimático, composto principalmente por endo 1,4 xilanase e endo 1,3(4) β-glucanases (CE), sobre o desempenho produtivo, a digestibilidade de aminoácidos (AA) e a utilização da energia em frangos de corte. Foram alojados 2.016 frangos de corte machos Cobb x Cobb 500 de um dia de idade em 72 boxes experimentais. As aves foram distribuídas em delineamento inteiramente casualizado com 9 tratamentos, 8 repetições e 28 aves por unidade experimental. Os tratamentos consistiram de uma dieta controle, formulada com níveis usuais de energia metabolizável aparente (EMA) e aminoácidos digestíveis (AA dig.) sem a inclusão do CE; e 8 dietas com reduções de EMA (-80 e -120 kcal/kg) e de AA dig. (-3% e 6%), suplementadas ou não com 50 mg/kg do CE. Foi utilizado um programa alimentar de 3 fases: inicial (1 a 21 d), crescimento (22 a 35 d) e final (36 a 42 d). Todas as dietas foram formuladas a base de milho e farelo de soja e com 1% de Celite, utilizado como indicador indigestível. Ganho de peso, consumo de ração e conversão alimentar corrigida para mortalidade (CA) foram avaliados aos 21, 35 e 42 d. Nos dias 21 e 42, 4 aves por unidade experimental foram sacrificadas para coleta de conteúdo ileal e posterior determinação da energia digestivel ileal (EDI) e da digestibilidade de AA. Os dados foram submetidos à análise de variância e, quando significativas, as médias foram comparadas pelo teste de Student-Newman-Keuls a 5% de significância. Contrastes ortogonais foram realizados entre os tratamentos com reduções nutricionais com e sem adição do CE. Frangos alimentados com dietas com reduções de energia e de AA dig. sem a adição do CE apresentaram maior CA e menor EDI quando comparados aos frangos que receberam a suplementação do CE. A suplementação do CE nas dietas aumentou a digestibilidade total de AA aos 21 d, porém não houve efeito aos 42 dias. A maior liberação de energia proporcionada pelo CE foi observada aos 21 d em frangos de corte alimentados com dietas com -120 kcal/kg AME e -6% AA dig., sendo 5,8% maior quando comparados aos alimentados com a dieta análoga sem enzima. Conclui-se que a adição do CE melhorou o desempenho produtivo e resultou em aumento da digestibilidade de AA e do aproveitamento da energia em frangos de corte aos 21 e aos 42 d. / The objective of this study was to evaluate the effect of supplementation of an enzyme complex, composed of endo 1,4 xylanase and endo 1,3 (4) β-glucanases (EC), on the productive performance, amino acid digestibility (AA) and the use of energy in broilers. A total of 2,016 one-day-old Cobb x Cobb 500 male broilers were allocated in 72 floor pens. Chicks were distributed into 9 treatments with 8 replicates of 28 birds each in a completely randomized design. Treatments consisted of a control diet formulated with usual apparent metabolizable energy (AME) and nutrient levels without enzyme supplementation as well as 8 diets having reductions in formulated AME (-80 and -120 kcal/kg) and digestible amino acids (dig. AA; -3 and -6%) supplemented or not with 50 mg/kg of the supplemental enzyme complex. A 3 phases feeding program was used: Starter (1 to 21 d), Grower (22 to 35 d) and Finisher (36 to 42 d). All diets were corn-soybean meal based with 1% of Celite, used as marker. Body weight gain, feed intake and feed conversion corrected for the weight of dead birds (FCR) were evaluated at 21, 35 and 42 d. On days 21 and 42, four birds per experimental unit were sacrificed for ileal content collection and subsequent determination of ileal digestible energy (IDE) and AA digestibility. Data were submitted to analysis of variance and, when significant, the means were compared by the Student-Newman-Keuls test at 5% significance. Orthogonal contrasts were performed between treatments with nutritional reductions with and without EC addition. Diets with AME and dig. AA reductions without enzyme had higher FCR and lower IDE (P < 0.05). The supplemental enzyme increased total AA digestibility at 21 d; however, no effects were observed at 42 d. The highest energy improvement provided by the supplemental enzyme was observed at 21 d on broilers fed diets with -120 kcal/kg AME and -6% dig. AA, being 5.8% higher when compared to those fed the analogous diet without enzyme. Summarizing, the addition of EC led to improvements on growth performance, digestibility of AA and energy utilization on broilers at 21 and 42 d.
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Meta-analysis of the response of broilers to the digestible lysine intake /

Gobi, Jaqueline de Paula. January 2015 (has links)
Orientador: Luciano Hauschild / Coorientador: Ines Andretta / Banca: Edney Pereira da Silva / Banca: Charles Kiefer / Resumo: Numerosos estudos estão sendo publicados para avaliar os efeitos do consumo de lisina sobre o desempenho de frangos de corte, no entanto, tais estudos diferem em seus resultados, principalmente devido à variabilidade existente nas condições experimentais. Uma meta-análise foi realizada para conduzir a informação disponível neste campo de pesquisa e estudar a resposta de lisina em dietas para frangos de corte. Os dados de diferentes níveis de lisina 104 experimentos dose-resposta oriundos de 66.726 frangos de corte foram utilizados neste banco de dados. Codificações foram usadas com critérios de agrupamento qualitativo e como moderador nas variáveis analisadas. O banco de dados foi dividido em quatro grupos: machos em fase inicial (de 1 a 21 dias de idade); machos em fase de crescimento (22-42 dias de idade); fêmeas em fase inicial (de 1 a 21 dias de idade); e fêmeas em fase de crescimento (22-42 dias de idade). Análises gráficas foram usadas para explorar a base de dados, ao passo que equações foram utilizadas para estudar o estudo das respostas das variáveis dependentes em cada grupo anteriormente descrito. Essas equações foram geradas através de análises sequenciais usando modelos de efeitos fixos e de efeitos aleatórios. Menores variâncias foram observados em modelos equipados usando dados de frangos de corte machos, comparando com os dados de fêmeas. A utilização de componentes aleatórios permitiu que os modelos explicassem a variabilidade na base de dados e reduzir a variação de 67% em média para machos e fêmeas nos períodos: inicial e crescimento, em comparação com o modelo de efeito fixo. O ganho de peso médio diário foi maximizado num... / Abstract: Numerous publications are being published evaluating the effects of lysine intake on broiler performance, however, showing differing results mainly due to the variability in the experimental conditions. A meta-analysis was conducted to address the available information in this research field and study the response of lysine in diets for broilers. Data of 104 dose-response experiments testing different dietary lysine levels for 66.726 broilers were used in this database. Codifications were used with qualitative grouping criteria and as moderating variables in the analysis. The database was subdivided into four groups, which were: males in initial phase (from 1 to 21 days of old); males in growth phase (from 22 to 42 days of old); females in initial phase (from 1 to 21 days of old); and females in growth phase (from 22 to 42 days of old). Graphical analyses were used to explore the database, whereas equations were used to study study the response of dependent variables in each group previously described. These equations were generated through sequential analysis using fixed-effects and random-effects models. Lower variance responses were observed in models fitted using data of male broilers comparing to the female treatments. Using random components allowed the models to account for the variability in the database and to reduce the variance by 67% in average for males and females in initial and growing comparing to the fixed-effect model. Average Daily Gain was maximized at dietary digestible lysine intake of 0,526 and 1,364 grams day-1 for males in the initial and growth phases ... / Mestre
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Avaliação do metabolismo proteico e aminoacídico de cães com shunt portossistêmico / Evaluation of amino acid and protein metabolism in dogs with portosystemic shunt

Ernandes, Mariane Ceschin 31 August 2018 (has links)
No desvio portossistêmico, o sangue proveniente do trato gastrintestinal não é direcionado ao fígado para ser metabolizado e sim desviado para a circulação sistêmica. O acúmulo dessas substâncias tóxicas associado às alterações funcionais do órgão pode resultar em encefalopatia hepática. O manejo nutricional é o ponto chave para o sucesso da terapia. Dessa forma, o presente estudo objetivou avaliar os efeitos do emprego de um alimento hipoproteico nas concentrações séricas aminoacídicas de cães com desvio portossistêmico. Foram incluídos nove cães com diagnóstico de desvio portossistêmico (Shunt) e nove cães saudáveis (Controle). Os animais foram avaliados no dia um (T0) e após 60 dias (T60) de ingestão de uma dieta hipoproteica comercial. Nos dois momentos foram coletadas amostras de sangue para realização de hemograma, leucograma, bioquímica sérica, determinação dos aminoácidos séricos e amônia. A análise estatística dos resultados referentes aos hemogramas e exames bioquímicos foi baseada em um modelo misto que considerou efeito fixos de grupo, tempo e interação e, para os aminoácidos somente efeitos fixos de grupo (p&lt;0,05). Os animais do grupo controle apresentaram maiores valores de proteína total (p&lt;0,0001), ureia (p&lt;0,0001), creatinina (p=0,0163), albumina (p&lt;0,0001) e colesterol (p=0,0012) quando comparado ao grupo Shunt que apresentou maiores valores de hematócrito (p=0,0213), ALT e FA (p=0,0253 e p=0,0004, respectivamente), amônia em jejum (p=0,0083) e amônia pós-prandial (p=0,0036). Em relação aos aminoácidos séricos, o grupo Shunt apresentou valores maiores quando comparados ao grupo Controle nas concentrações dos aminoácidos fenilalanina (p=0,0054), glutamato (p=0,0066), serina (p=0,0054) e tirosina (p=0,0106), já o aminoácido sérico alanina (p=0,0280), a razão de Fischer (p=0,0093) e a razão da concentração sérica de aminoácidos de cadeia ramificada e tirosina (p=0,0243) foram maiores no grupo Controle. Concluiu-se que o manejo dietético foi eficiente em prevenir a progressão da doença e controlar os sinais clínicos, sem promover aumento nas concentrações séricas dos aminoácidos de cadeia ramificada. / In the portosystemic shunt, the blood coming from the gastrointestinal tract is not directed to the liver to be metabolized but rather diverted to the systemic circulation. The accumulation of these toxic substances associated with functional alterations of the organ can result in hepatic encephalopathy. Nutritional management is the key to successful therapy. Thus, the present study aimed to evaluate the effects of the use of a hypoproteic food on the protein and amino acid profile of dogs with portosystemic shunt. For this, nine dogs with a diagnosis of portosystemic shunt (Shunt) and nine healthy dogs (Control) were included. The dogs were evaluated on day one (T0) and after 60 days (T60) feeding a commercial hypoprotein diet. Blood samples were collected for hemogram, leukogram, serum biochemistry, determination of serum amino acids and ammonia. For the analysis of hemograms and biochemistry, a mixed model was used considering group fixed effects, time and interaction, and for amino acids only group fixed effects (p&lt;0.05). The results showed that the animals in the Control group presented higher values of total protein (p&lt;0.0001), urea (p&lt;0.0001), creatinine (p=0.0163), albumin (p&lt;0.0001) and cholesterol (p=0.0012) when compared to the Shunt group that presented higher values of hematocrit (p=0.0213), ALT and FA (p=0.0253 and p=0.0004, respectively), fasting ammonia (p=0.0083) and postprandial ammonia (p=0.0036). Serum amino acids (p=0.0054), glutamate (p=0.0066), serine (p=0.0054) and tyrosine (p=0.0054) were higher in the Shunt group than in the Control group (0.0106). The Fischer ratio (p=0.0093) and the ratio of serum concentration of branched-chain amino acids and tyrosine (p=0.0243) were higher for the Control group. In conclusion, that dietary management was efficient in preventing disease progression and controlling clinical signs without increasing branched-chain amino acids.

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