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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.
11

Desempenho, qualidade dos ovos e balanço de nitrogênio de poedeiras comerciais alimentadas com diferentes níveis de proteína bruta, metionina e lisina / Performance, egg quality, and nitrogen balance of commercial laying hens fed different dietary levels of crude protein, methionine and lysine

Mayra Fernanda Rizzo Silva 20 July 2006 (has links)
Foram conduzidos dois experimentos com um total de 416 poedeiras Hisex White, com os objetivos de avaliar os efeitos de diferentes níveis dietários de proteína bruta (PB) e de lisina (LIS) sobre as características de desempenho, qualidade interna dos ovos e determinar o balanço e o coeficiente de metabolizabilidade aparente do nitrogênio (Experimento 1) e avaliar os efeitos de diferentes níveis dietários de LIS e metionina (MET) sobre o desempenho, qualidade interna dos ovos e propriedades funcionais dos componentes dos ovos (Experimento 2). No Experimento 1, foram utilizadas 160 poedeiras alojadas individualmente e submetidas ao delineamento inteiramente casualizado (DIC) em esquema fatorial 4 x 2, com os fatores: níveis de PB (12%, 14%, 16% e 18%) e de LIS (0,85% e 1,00%), totalizando oito tratamentos com cinco repetições de quatro aves cada. No Experimento 2, foram utilizadas 256 poedeiras alojadas individualmente e submetidas ao DIC em arranjo fatorial 4x4, com os fatores: níveis de LIS (0,482%, 0,682%, 0,882% e 1,082%) e de MET (0,225%, 0,318%, 0,411% e 0,505%), totalizando 16 tratamentos com quatro repetições de quatro aves cada. O desempenho foi avaliado por meio das características consumos de ração (CR), lisina (CLIS), metionina (CMET), proteína bruta (CPB) e de energia (CE), peso (PO), produção (PROD) e massa de ovos (MO), e conversão alimentar (CA). As características CPB, PO e MO tiveram respostas linear crescente. A qualidade interna dos ovos foi avaliada por meio das características peso e porcentagens de albúmen (ALB%) e gema (GEM%), e unidade Haugh (UH). A ALB% apresentou diferença significativa com resposta linear crescente. Em ambos experimentos, a qualidade dos ovos armazenados foi mensurada pelas características UH, PO e altura de albúmen, as quais apresentaram melhores resultados quando os ovos foram conservados em ambiente refrigerado. No entanto, independente do ambiente, a qualidade dos ovos piorou com o aumento do tempo de armazenamento. Respostas máximas das análises de proteína, sólidos totais, viscosidade e pH dos componentes albúmen e gema, foram obtidas quando as aves foram alimentadas com a concentração média de 15,33% de PB na dieta. No Experimento 1, após o término do período experimental foram realizadas coletas das excretas por um período de três dias para cálculo do balanço de nitrogênio, sendo observado aumento significativo da ingestão e excreção de nitrogênio conforme o incremento de PB na dieta. No experimento 2, as características CR, CMET, CE, PROD, PO e MO apresentaram resposta máxima quando as aves foram alimentadas com as concentrações dietárias médias de 0,870% de LIS e de 0,450% de MET. A classificação dos ovos por tipo e as características de qualidade interna e externa dos ovos não sofreram influência dos diferentes níveis dietários de MET e LIS. As propriedades funcionais dos componentes albúmen e gema foram avaliadas por meio da qualidade do cozimento com a confecção de bolos tipos Angel e Sponge cakes, a qual não foi influenciada pelos tratamentos. Conclui-se que níveis médios de 15,33% de PB, 0,450% de MET e 0,870% de LIS satisfazem as exigências das poedeiras para as características avaliadas. / Four hundred sixteen Hisex White hens were used to evaluate the effects of different dietary levels of crude protein (CP) and lysine (LYS) on performance, internal egg quality and to determine the nitrogen balance and its apparent metabolizability coefficient (Experiment 1), and to evaluate the effects of different dietary levels of LYS and methionine (MET) on performance, internal egg quality and functional properties of egg components (Experiment 2). One hundred sixty hens were randomly distributed in a 4 x 2 factorial scheme: CP levels (12%, 14%, 16% and 18%) and LYS levels (0,85% and 1,00%) totalizing eight treatments with five replicates of four birds each (Experiment 1). Two hundred fifty six hens were randomly distributed in a 4 x 4 factorial scheme: LYS levels (0,482%, 0,682%, 0,882% and 1,082%) and MET levels (0,225%, 0,318%, 0,411% and 0,505%) totalizing sixteen treatments with four replicates of four birds each (Experiment 2). Several characteristics were evaluated such as performance: intakes of feed, LYS, MET, CP and energy, egg production, egg weight, egg mass, and feed conversion; internal egg quality: weight and percentages of egg albumen and egg yolk, Haugh unit; quality of storaged eggs: Haugh unit, egg weight and albumen height; analyses of concentrations of protein, total solids, viscosity and pH of the egg components. The characteristics intake of CP, egg weight, egg mass, and albumen percent showed positive and linear response. In both experiments, the quality of storaged eggs was better when eggs were storaged in refrigerated environment than natural environment. However, irrespective of the environment, the internal egg quality was impaired as the time of storage was increased. Maximum responses for analyses of protein, total solids, viscosity, and pH of albumen and yolk were obtained when hens were fed diets containing 15,33% of CP. In the Experiment 1, after the experimental period, another assay was carried out to determine the nitrogen balance by using total excreta procedure during a three-day period. It was observed increase of intake and excretion of nitrogen as the content of CP in the diet was increased. In the Experiment 2, feed intake, MET intake, energy intake, egg production, egg weight, and egg mass showed maximum responses when hens were fed diets containing 0,870% of LYS and 0,450% of MET. Egg grading, internal and external egg quality characteristics were not influenced by the different dietary levels of MET and LYS. The functional properties of egg components (cooking quality by making Angel and Sponge cakes) were not affected by the treatments. It was concluded that hens fed diets containing 15,33% of CP, 0,450% of MET, and 0,870% of LYS show optimum performance, internal and external egg quality.
12

Níveis dietéticos de metionina e cobre quelatado, treonina e zinco quelatado sobre a composição química do ovo e o teor de colesterol da gema / Dietary levels of methionine and chelated copper, threonine and chelated zinc on the chemical composition of the egg and the yolk cholesterol

Janaina Cristina da Silva Maciel de Souza 25 August 2017 (has links)
Na avicultura de postura, a associação dos aminoácidos e minerais quelatados pode afetar positivamente a composição química dos ovos e o colesterol da gema. Desta forma, em dois ensaios experimentais distintos, objetivou-se com avaliar a interação do nível dietético de metionina e cistina com o cobre quelatado e treonina e zinco quelatado sobre a composição química do ovo. Para tanto, foram utilizados em cada ensaio 320 poedeiras comerciais, distribuídas sob o delineamento inteiramente casualizado. Os tratamentos, distribuídos aleatoriamente em quatro repetições, foram organizados em arranjo fatorial 5 x 4: sendo o primeiro fator teor de aminoácido e o segundo nível do mineral quelatado, constituindo 20 tratamentos, com quatro repetições e quatro aves por unidade experimentais. A parcela experimental era constituída de quatro aves com 48 semanas de idade. No primeiro ensaio os níveis totais de metionina+ cistina (met+cys) eram: 0,613, 0,631, 0,816, 0,918 e 0,955 % e os de cobre (Cu): 18, 44, 71 e 99 mg / kg. No segundo, eram: níveis totais de treonina (Thr) 0,614, 0,698, 0,875, 1,006, 1,055%; e. zinco (Zn): 31, 73, 104 e 121 mg / kg. Os níveis avaliados foram estabelecidos após análises laboratoriais. Em ambos os experimentos, foram avaliados: ovos e conteúdos, taxas diárias de deposição, composição química dos conteúdos na Matéria Natural (MN) e Matéria Seca (MS). Para as determinações da composição química PB%, EE%, MM%, H2O% e colesterol dos ovos, foram colhidos dois ovos por parcela. Os dados foram analisados utilizando-se o procedimento SISVAR 5.6 e o nível de significância considerado foi de 5%. No ensaio 1, o efeito de interação (P < 0,05) entre Met + Cys*Cu, foi observado para maioria das variáveis avaliadas. Entretanto, foram observados efeito principal (P < 0,05) de Met+ Cys para as seguintes variáveis: peso de casca e gema; deposição de Nitrogênio (N), Extrato Etéreo no Albúmen (EE no Alb) e Cinzas, composição química do ovo nas Matérias Natural e Seca; Proteína Bruta (PB), Extrato Etéreo (EE) e Cinzas no Albúmen, ovo reconstituído e MS no Alb, e para colesterol total. O efeito do aumento nos níveis de Met + Cys resultou em acréscimo de 18,17 % no teor de colesterol. Ensaio 2: Foi observado efeito de interação (P <0,05) entre Thr* Zn, para maioria das variáveis analisadas. Todavia, foi observado efeito principal (P< 0,05) do aminoácido para as seguintes variáveis: pesos de casca e gema, na composição química do ovo na MN (EE na gema), onde o aumento nos níveis de Thr resultaram no aumento do EE na gema, para o colesterol total. Conclui-se que em ambos os experimentos a utilização mineral quelatado em dietas para poedeiras pode trazer benefícios para qualidade do ovo, melhorando alguns parâmetros da composição química do ovo. / In laying hens production, an association of amino acids and chelated minerals can positively affect a chemical composition and yolk cholesterol.of the eggs. Thus, the objective was to evaluate the interaction of the dietary level of methionine and cystine with the chelated copper and chelated threonine and zinc on the chemical composition of the egg, in two different experimental trials. For this, 320 commercial layers were used in each experiment, distributed under a completely randomized design. The treatments, were randomly distributed in four replications, in a 5 x 4 factorial arrangement of treatments, with five levels of the factor amino acid content and four levels of the factor chelated mineral concentration, constituting 20 treatments, with 4 replicates and 4 layers per experimental unit. The experimental plot consisted of four birds with 48 weeks of age. In the first trial, the total methionine + cystine (Met + Cys) levels were: 0.613, 0.631, 0.816, 0.918 e 0.955% and cooper (Cu): 18, 44, 71 e 99 mg / kg. In the second trial, the total threonine (Thr) levels were: 0.614, 0.698, 0.875, 1.006, 1.055%, and zinc (Zn): 31, 73, 104 e 121 mg / kg. The levels assessed were established after laboratory analysis. In both experiments, were evaluated: eggs and contents, daily rates of deposition, chemical composition of contents in natural matter (NM) and dry matter (DM). For the determinations of the chemical composition (PB%, EE%, MM%, H2O% and cholesterol of the eggs), two eggs were collected per plot. Data were analyzed using the SISVAR 5.6 procedure and the level of significance considered was 0.05. Experiment 1: the interaction effect (P < 0.05) between Met + Cys*Cu was observed for most of the evaluated variables. However, the main effect of Met + Cys was observed (P < 0.05) for the following variables: egg shell and yolk weight; deposition of nitrogen (N), ether extract (EE) in albumen and ash; chemical composition of the egg in natural and dry matter (CP, EE and Ash in the albumen, reconstituted egg and DM in albumen) for the total cholesterol. The effect of the increase in a Met + Cys levels resulted in an increase of 18.17% in the cholesterol content. Experiment 2: the interaction effect (P < 0.05) between Thr* Zn was observed for most of the observed variables. However, the main effect (P < 0.05) of the amino acid was observed for the following variables: egg shell and yolk weights, in the chemical composition of the egg in the NM (EE yolk), where the increase in Thr levels resulted in increased of yolk EE, Therefore, it is concluded that in both experiments the chelated mineral utilization in laying diets can bring benefits to egg quality, improving some parameters of the egg chemical composition.
13

Níveis dietéticos de metionina e cobre quelatado, treonina e zinco quelatado sobre a composição química do ovo e o teor de colesterol da gema / Dietary levels of methionine and chelated copper, threonine and chelated zinc on the chemical composition of the egg and the yolk cholesterol

Souza, Janaina Cristina da Silva Maciel de 25 August 2017 (has links)
Na avicultura de postura, a associação dos aminoácidos e minerais quelatados pode afetar positivamente a composição química dos ovos e o colesterol da gema. Desta forma, em dois ensaios experimentais distintos, objetivou-se com avaliar a interação do nível dietético de metionina e cistina com o cobre quelatado e treonina e zinco quelatado sobre a composição química do ovo. Para tanto, foram utilizados em cada ensaio 320 poedeiras comerciais, distribuídas sob o delineamento inteiramente casualizado. Os tratamentos, distribuídos aleatoriamente em quatro repetições, foram organizados em arranjo fatorial 5 x 4: sendo o primeiro fator teor de aminoácido e o segundo nível do mineral quelatado, constituindo 20 tratamentos, com quatro repetições e quatro aves por unidade experimentais. A parcela experimental era constituída de quatro aves com 48 semanas de idade. No primeiro ensaio os níveis totais de metionina+ cistina (met+cys) eram: 0,613, 0,631, 0,816, 0,918 e 0,955 % e os de cobre (Cu): 18, 44, 71 e 99 mg / kg. No segundo, eram: níveis totais de treonina (Thr) 0,614, 0,698, 0,875, 1,006, 1,055%; e. zinco (Zn): 31, 73, 104 e 121 mg / kg. Os níveis avaliados foram estabelecidos após análises laboratoriais. Em ambos os experimentos, foram avaliados: ovos e conteúdos, taxas diárias de deposição, composição química dos conteúdos na Matéria Natural (MN) e Matéria Seca (MS). Para as determinações da composição química PB%, EE%, MM%, H2O% e colesterol dos ovos, foram colhidos dois ovos por parcela. Os dados foram analisados utilizando-se o procedimento SISVAR 5.6 e o nível de significância considerado foi de 5%. No ensaio 1, o efeito de interação (P < 0,05) entre Met + Cys*Cu, foi observado para maioria das variáveis avaliadas. Entretanto, foram observados efeito principal (P < 0,05) de Met+ Cys para as seguintes variáveis: peso de casca e gema; deposição de Nitrogênio (N), Extrato Etéreo no Albúmen (EE no Alb) e Cinzas, composição química do ovo nas Matérias Natural e Seca; Proteína Bruta (PB), Extrato Etéreo (EE) e Cinzas no Albúmen, ovo reconstituído e MS no Alb, e para colesterol total. O efeito do aumento nos níveis de Met + Cys resultou em acréscimo de 18,17 % no teor de colesterol. Ensaio 2: Foi observado efeito de interação (P <0,05) entre Thr* Zn, para maioria das variáveis analisadas. Todavia, foi observado efeito principal (P< 0,05) do aminoácido para as seguintes variáveis: pesos de casca e gema, na composição química do ovo na MN (EE na gema), onde o aumento nos níveis de Thr resultaram no aumento do EE na gema, para o colesterol total. Conclui-se que em ambos os experimentos a utilização mineral quelatado em dietas para poedeiras pode trazer benefícios para qualidade do ovo, melhorando alguns parâmetros da composição química do ovo. / In laying hens production, an association of amino acids and chelated minerals can positively affect a chemical composition and yolk cholesterol.of the eggs. Thus, the objective was to evaluate the interaction of the dietary level of methionine and cystine with the chelated copper and chelated threonine and zinc on the chemical composition of the egg, in two different experimental trials. For this, 320 commercial layers were used in each experiment, distributed under a completely randomized design. The treatments, were randomly distributed in four replications, in a 5 x 4 factorial arrangement of treatments, with five levels of the factor amino acid content and four levels of the factor chelated mineral concentration, constituting 20 treatments, with 4 replicates and 4 layers per experimental unit. The experimental plot consisted of four birds with 48 weeks of age. In the first trial, the total methionine + cystine (Met + Cys) levels were: 0.613, 0.631, 0.816, 0.918 e 0.955% and cooper (Cu): 18, 44, 71 e 99 mg / kg. In the second trial, the total threonine (Thr) levels were: 0.614, 0.698, 0.875, 1.006, 1.055%, and zinc (Zn): 31, 73, 104 e 121 mg / kg. The levels assessed were established after laboratory analysis. In both experiments, were evaluated: eggs and contents, daily rates of deposition, chemical composition of contents in natural matter (NM) and dry matter (DM). For the determinations of the chemical composition (PB%, EE%, MM%, H2O% and cholesterol of the eggs), two eggs were collected per plot. Data were analyzed using the SISVAR 5.6 procedure and the level of significance considered was 0.05. Experiment 1: the interaction effect (P < 0.05) between Met + Cys*Cu was observed for most of the evaluated variables. However, the main effect of Met + Cys was observed (P < 0.05) for the following variables: egg shell and yolk weight; deposition of nitrogen (N), ether extract (EE) in albumen and ash; chemical composition of the egg in natural and dry matter (CP, EE and Ash in the albumen, reconstituted egg and DM in albumen) for the total cholesterol. The effect of the increase in a Met + Cys levels resulted in an increase of 18.17% in the cholesterol content. Experiment 2: the interaction effect (P < 0.05) between Thr* Zn was observed for most of the observed variables. However, the main effect (P < 0.05) of the amino acid was observed for the following variables: egg shell and yolk weights, in the chemical composition of the egg in the NM (EE yolk), where the increase in Thr levels resulted in increased of yolk EE, Therefore, it is concluded that in both experiments the chelated mineral utilization in laying diets can bring benefits to egg quality, improving some parameters of the egg chemical composition.
14

Teplotně závislá antimikrobiální aktivita bílkových proteinů u prekociálních a altriciálních druhů ptáků / Temperature-dependent activity of egg-white antimicrobial proteins in precocial and altricial birds

Novotná, Lucie January 2015 (has links)
Microorganisms are considered to be crucial selective factor affecting reproductive success of birds. It is hypothesized that egg-white antimicrobial proteins and incubation behavior are the most important defense mechanisms that eliminates the risk of microbial trans-shell infection. The latest studies supposed that incubation temperatures may significantly affect the antimicrobial activity of egg white proteins. The concentration of egg white antimicrobial proteins as well as incubation patterns differ among altricial and precocial species of birds. However, experimental study testing the effect of incubation temperature on the antimicrobial potential of antimicrobial egg white proteins in altricial and precocial birds is missing. In this study we tested in manipulative experiment the effect of partial and full incubation, the concentration of lysozyme and ovotransferrin and their interactions on the antimicrobial activity of egg whites of two model species - Japanese quail (Coturnix japonica) and home pigeon (Columba livia). Antimicrobial protein activity was determined by the agar well diffusion method against two Gram-positive bacteria - Bacillus subtilis and Micrococcus luteus that have been documented as pathogenic egg-white invaders of several birds. Moreover, we analyzed the effect of...
15

Vibrações no transporte de ovos fertilizados: efeitos no nascimento e na qualidade de pintos de corte / Vibrations on transport of fertile eggs: implications during birth and on the quality of broiler chicks

Donofre, Ana Carolina 10 March 2014 (has links)
O objetivo deste trabalho foi avaliar os efeitos das vibrações mecânicas decorrentes do transporte sobre a qualidade de ovos fertilizados e sobre o nascimento e a qualidade de pintos de corte. O experimento foi dividido em duas fases desenvolvidas em um incubatório comercial em Mogi-Mirim/SP. Na primeira, 1920 ovos fertilizados de matrizes da linhagem Cobb-500 (31 a 34 semanas) foram expostos a simulações dos movimentos vibratórios, produzidos por um agitador mecânico desenvolvido para este fim. Na segunda fase, esses ovos foram incubados até o nascimento das aves. Avaliaram-se os efeitos de diferentes intensidades de vibração e tempos de exposição sobre as respostas de interesse. A intensidade foi definida por duas faixas de vibração simuladas pelo agitador (faixa inferior; RSS de 2,5 m.s-2 e faixa superior; RSS de 7,5 m.s-2), as quais foram associadas a dois tempos de exposição, um mínimo e um máximo (60 e 180 minutos, respectivamente). Foi adotado um delineamento aleatorizado em blocos com tratamentos em esquema fatorial mais um controle (2 x 2 + 1). A qualidade dos ovos fertilizados foi mensurada a partir da perda de peso e de medidas tomadas na gema e no albúmen (altura, diâmetro e índices, e unidade Haugh). Pela análise de variância foi possível observar efeitos dos fatores experimentais na qualidade dos ovos fertilizados, principalmente nas medidas tomadas no albúmen. Os resultados indicaram que os ovos quando expostos às vibrações, em faixas mais intensas e/ou por mais tempo, apresentam seu albúmen liquefeito, o que é um sinal de perda de qualidade. Esses resultados foram comprovados pela redução no índice de albúmen e na unidade Haugh, quando realizados os testes t e de Tukey a 5% de significância. Após o nascimento das aves foi avaliada a taxa de eclodibilidade, a caracterização da mortalidade e a qualidade dos pintos de corte (peso absoluto e classificação). Por meio da regressão logística, observou-se que a exposição dos ovos fertilizados às vibrações pode afetar negativamente a taxa de eclodibilidade e a proporção de pintos classificados em primeira linha. Essas respostas foram menores pelo teste de Wald a 5% de significância no tratamento formado pela faixa de vibração superior aplicada por mais tempo. Os piores resultados no nascimento refletiram diretamente em um aumento nas perdas totais devido à exposição dos ovos aos movimentos vibratórios, com a significância de efeito comprovada principalmente pela a faixa de vibração. Além disso, pela análise de variância foi observada uma pequena redução do peso das aves nascidas de ovos vibrados, quando feita a comparação de médias pelo teste t com o controle. Por fim, acredita-se que o comprometimento da qualidade do albúmen tenha gerado piores resultados no nascimento e na qualidade dos pintos de corte. Dessa forma, é possível concluir que a exposição às vibrações pode comprometer a incubação e gerar prejuízos de grandes dimensões para os incubatórios, caso ocorram em condições semelhantes às simuladas nesta pesquisa. / The aim of this research was to evaluate the effects of mechanical vibrations during birth, and on the quality of fertile eggs and broiler chicks due to transportation. The experiment was divided in two phases developed in a commercial incubator in Mogi-Mirim, São Paulo. In the first phase, 1920 fertile eggs from Cobb-500 matrix (31 to 34 weeks) were used. These eggs were exposed to vibrations in a mechanical simulator. In the second phase, the eggs were incubated until the moment of birth. The effects of different vibration intensities and time exposition upon different feed backs were assessed. The intensity was defined by two vibration levels simulated by a mechanical agitator (inferior level; RSS - 2.5 m.s-2; superior level; RSS - 7.5 m.s-2), in which were associated to two different exposition periods of time (minimum, 60 minutes; and maximum, 180 minutes, respectively). A modeling in blocks with treatments in a factorial treatment and a control (2 x 2 +1) was chosen randomly. The quality of fertile eggs was evaluated considering the weight loss and measurements taken in the egg yolk and in the albumen (height, diameter, indexes, and Haugh unity). Using the analysis of variance, it was possible to observe the effects of experimental factors on the quality of fertile eggs, mainly, in the measurements found in the albumen. The results indicated that the eggs that were exposed to vibrations in very intense levels, and/or for more time, presented liquefied albumen, showing quality loss. These results were seen by the reduction in the albumen index as well as in the Haugh unity, found in the Tukey test submitted to the level of significance of 5%. After birth, the hatching tax, the mortality characterization, and the quality of broiler chicks (absolute weight and classification) were evaluated. Using the logistical regression, it was possible to observe that fertile eggs exposed to vibrations can affect negatively the hatching tax and the proportion of chicks classified in first line. These results were found smaller in the Wald test at significance of 5% in the treatment formed by the superior vibration level applied for a longer period of time. The worst results found in birth demonstrated an increase in total loss because of vibration exposition on the eggs with a significance effect proved, mainly, by the vibration level. Furthermore, through the analysis of variance, it was observed a small weight reduction of birds hatched from vibrated eggs. These results were observed when they were compared to the averages found in the control group and t test. Thus, if the albumen quality is compromised it is believed that it generates worst results in birth and in the quality of broiler chicks. Hence, it is possible to conclude that vibrations are capable of compromise incubation, resulting in huge financial loss for incubators, if similar conditions happen to be the way they were simulated on this study.
16

Analyse du protéome de l'albumen et des couches périphériques du grain de blé (Triticum aestivum L.) en développement : vers une intégration des données avec le transcriptome

Tasleem-Tahir, Ayesha 04 July 2012 (has links) (PDF)
Le blé est la seconde céréale la plus produite dans le monde. Il constitue une importante source de denrées alimentaires et de beaucoup d'autres usages industriels. La compréhension des mécanismes impliqués dans le développement du grain de blé est fondamentale pour développer des blés à valeur ajoutée. La physiologie du grain de blé et les mécanismes moléculaires impliqués dans son développement nécessitent d'être mieux connus et ces connaissances pourront être très utiles pour l'amélioration du blé mais aussi des autres céréales. L'approche protéomique a été aussi utilisée dans ce contexte mais aucun travail n'avait jusqu'ici été réalisé sur la totalité des phases de développement des tissus et sur des intervalles de temps très courts. La caractérisation des changements d'expressions protéiques dans les couches périphériques du grain et de l'albumen est présentée dans cette étude. Nous avons utilisé les grains de Triticum aestivum de la variété Récital, cultivés à l'INRA de Clermont-Ferrand. Les grains ont été prélevés tous les 50°C jour (°Cj) depuis la fécondation jusqu'à la maturité sur 15 stades de développement pour les couches périphériques et sur 21 stades pour l'albumen amylacé. Pour chaque échantillon, les couches périphériques des grains ont été disséquées et les protéines totales extraites. L'analyse des protéines en électrophorèse bidimensionnelle puis par spectrométrie de masse MALDI-TOF a permis d'identifier via l'interrogation des bases de données, 207 protéines différentiellement exprimées sur 15 stades de développement (0°Cj-700°Cj). Ces protéines ont ensuite été classées en 16 classes fonctionnelles. L'analyse en cluster a révélé 5 profils d'expression au cours du temps. Parallèlement, l'albumen amylacé a été isolé des grains et les protéines métaboliques de ce tissu extraites. Après électrophorèse bidimensionnelle des protéines, 487 protéines variant significativement dans l'albumen sur l'ensemble des stades de développement (0°Cj-1006°Cj) ont été identifiées par utilisation de la LC-MS. Les protéines ont été réparties sur neuf profils d'expression et 17 fonctions biochimiques. Le protéome des couches périphériques a ensuite été comparé au protéome de l'albumen dans le but de comprendre si l'évolution des processus biochimiques diffère dans chacun de ces tissus. Au final, nous avons optimisé l'intégration des données protéomiques avec celles du transcriptome (en se focalisant sur les protéines du métabolisme carboné). Seulement 32% des profils d'expression protéome/transcriptome montrent une corrélation significative au cours du développement (152°Cj-700°Cj). Les profils d'expression des enzymes ont été comparés sur les deux niveaux. Ils devraient permettre de distinguer les processus régulés au niveau du transcriptome de ceux régulés au niveau du protéome. L'ensemble de ces données pourra être compilé dans une base de données propre de la variété Récital et utilisé comme référence dans l'étude des maladies et des stress abiotiques des tissus du grain de blé en développement.
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Contribution à la validation fonctionnelle du gène majeur contrôlant la dureté / tendreté de l'albumen du grain de blé par l'étude de lignées quasi-isogéniques

Lesage, Véronique 15 December 2011 (has links) (PDF)
La dureté du grain de blé est un des paramètres fondamentaux de la texture de l'albumen. Ce caractère, essentiel pour la valeur d'utilisation des farines, est fortement lié à l'absence ou à la modification des puroindolines. Afin de mieux comprendre la fonction biologique de ces protéines dans le grain de blé (Triticum aestivum L.), nous avons étudié à quatre stades de développement du grain la localisation subcellulaire des puroindolines par immunocytochimie et les protéomes dans deux lignées de blé quasi-isogéniques pour la dureté. Dès la fin de la cellularisation de l'albumen, les puroindolines sont localisées sur la face interne des membranes vésiculaires et dans les corps protéiques en formation, structures dans lesquelles s'accumulent les protéines de réserve du grain. L'analyse par AFFFF (Asymmetrical Flow Field-Flow Fractionation) des deux lignées Hard et Soft, qui diffèrent essentiellement par l'absence du gène Pina dans la lignée Hard, a montré une corrélation entre la dureté et la taille des polymères de protéines de réserve. L'analyse protéomique des fractions albumines/globulines et amphiphiles des grains en développement a révélé une augmentation des protéines de la machinerie de repliement et de réponse au stress dans la lignée Hard, par rapport à la lignée Soft. Les deux approches méthodologiques utilisées semblent également mettre en évidence une cinétique de développement du grain raccourcie dans la lignée Hard. Ces observations suggèrent que les puroindolines interagissent avec les protéines de réserve du grain et suivent le même routage cellulaire. Elles pourraient être impliquées dans les mécanismes de repliement et d'assemblage des prolamines.
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Vibrações no transporte de ovos fertilizados: efeitos no nascimento e na qualidade de pintos de corte / Vibrations on transport of fertile eggs: implications during birth and on the quality of broiler chicks

Ana Carolina Donofre 10 March 2014 (has links)
O objetivo deste trabalho foi avaliar os efeitos das vibrações mecânicas decorrentes do transporte sobre a qualidade de ovos fertilizados e sobre o nascimento e a qualidade de pintos de corte. O experimento foi dividido em duas fases desenvolvidas em um incubatório comercial em Mogi-Mirim/SP. Na primeira, 1920 ovos fertilizados de matrizes da linhagem Cobb-500 (31 a 34 semanas) foram expostos a simulações dos movimentos vibratórios, produzidos por um agitador mecânico desenvolvido para este fim. Na segunda fase, esses ovos foram incubados até o nascimento das aves. Avaliaram-se os efeitos de diferentes intensidades de vibração e tempos de exposição sobre as respostas de interesse. A intensidade foi definida por duas faixas de vibração simuladas pelo agitador (faixa inferior; RSS de 2,5 m.s-2 e faixa superior; RSS de 7,5 m.s-2), as quais foram associadas a dois tempos de exposição, um mínimo e um máximo (60 e 180 minutos, respectivamente). Foi adotado um delineamento aleatorizado em blocos com tratamentos em esquema fatorial mais um controle (2 x 2 + 1). A qualidade dos ovos fertilizados foi mensurada a partir da perda de peso e de medidas tomadas na gema e no albúmen (altura, diâmetro e índices, e unidade Haugh). Pela análise de variância foi possível observar efeitos dos fatores experimentais na qualidade dos ovos fertilizados, principalmente nas medidas tomadas no albúmen. Os resultados indicaram que os ovos quando expostos às vibrações, em faixas mais intensas e/ou por mais tempo, apresentam seu albúmen liquefeito, o que é um sinal de perda de qualidade. Esses resultados foram comprovados pela redução no índice de albúmen e na unidade Haugh, quando realizados os testes t e de Tukey a 5% de significância. Após o nascimento das aves foi avaliada a taxa de eclodibilidade, a caracterização da mortalidade e a qualidade dos pintos de corte (peso absoluto e classificação). Por meio da regressão logística, observou-se que a exposição dos ovos fertilizados às vibrações pode afetar negativamente a taxa de eclodibilidade e a proporção de pintos classificados em primeira linha. Essas respostas foram menores pelo teste de Wald a 5% de significância no tratamento formado pela faixa de vibração superior aplicada por mais tempo. Os piores resultados no nascimento refletiram diretamente em um aumento nas perdas totais devido à exposição dos ovos aos movimentos vibratórios, com a significância de efeito comprovada principalmente pela a faixa de vibração. Além disso, pela análise de variância foi observada uma pequena redução do peso das aves nascidas de ovos vibrados, quando feita a comparação de médias pelo teste t com o controle. Por fim, acredita-se que o comprometimento da qualidade do albúmen tenha gerado piores resultados no nascimento e na qualidade dos pintos de corte. Dessa forma, é possível concluir que a exposição às vibrações pode comprometer a incubação e gerar prejuízos de grandes dimensões para os incubatórios, caso ocorram em condições semelhantes às simuladas nesta pesquisa. / The aim of this research was to evaluate the effects of mechanical vibrations during birth, and on the quality of fertile eggs and broiler chicks due to transportation. The experiment was divided in two phases developed in a commercial incubator in Mogi-Mirim, São Paulo. In the first phase, 1920 fertile eggs from Cobb-500 matrix (31 to 34 weeks) were used. These eggs were exposed to vibrations in a mechanical simulator. In the second phase, the eggs were incubated until the moment of birth. The effects of different vibration intensities and time exposition upon different feed backs were assessed. The intensity was defined by two vibration levels simulated by a mechanical agitator (inferior level; RSS - 2.5 m.s-2; superior level; RSS - 7.5 m.s-2), in which were associated to two different exposition periods of time (minimum, 60 minutes; and maximum, 180 minutes, respectively). A modeling in blocks with treatments in a factorial treatment and a control (2 x 2 +1) was chosen randomly. The quality of fertile eggs was evaluated considering the weight loss and measurements taken in the egg yolk and in the albumen (height, diameter, indexes, and Haugh unity). Using the analysis of variance, it was possible to observe the effects of experimental factors on the quality of fertile eggs, mainly, in the measurements found in the albumen. The results indicated that the eggs that were exposed to vibrations in very intense levels, and/or for more time, presented liquefied albumen, showing quality loss. These results were seen by the reduction in the albumen index as well as in the Haugh unity, found in the Tukey test submitted to the level of significance of 5%. After birth, the hatching tax, the mortality characterization, and the quality of broiler chicks (absolute weight and classification) were evaluated. Using the logistical regression, it was possible to observe that fertile eggs exposed to vibrations can affect negatively the hatching tax and the proportion of chicks classified in first line. These results were found smaller in the Wald test at significance of 5% in the treatment formed by the superior vibration level applied for a longer period of time. The worst results found in birth demonstrated an increase in total loss because of vibration exposition on the eggs with a significance effect proved, mainly, by the vibration level. Furthermore, through the analysis of variance, it was observed a small weight reduction of birds hatched from vibrated eggs. These results were observed when they were compared to the averages found in the control group and t test. Thus, if the albumen quality is compromised it is believed that it generates worst results in birth and in the quality of broiler chicks. Hence, it is possible to conclude that vibrations are capable of compromise incubation, resulting in huge financial loss for incubators, if similar conditions happen to be the way they were simulated on this study.
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Contribution à la validation fonctionnelle du gène majeur contrôlant la dureté / tendreté de l'albumen du grain de blé par l'étude de lignées quasi-isogéniques / Contribution to functional validation of the major gene controlling hardness / softness trait in bread wheat endosperm of near-isogenic lines

Lesage, Véronique 15 December 2011 (has links)
La dureté du grain de blé est un des paramètres fondamentaux de la texture de l’albumen. Ce caractère, essentiel pour la valeur d’utilisation des farines, est fortement lié à l’absence ou à la modification des puroindolines. Afin de mieux comprendre la fonction biologique de ces protéines dans le grain de blé (Triticum aestivum L.), nous avons étudié à quatre stades de développement du grain la localisation subcellulaire des puroindolines par immunocytochimie et les protéomes dans deux lignées de blé quasi-isogéniques pour la dureté. Dès la fin de la cellularisation de l’albumen, les puroindolines sont localisées sur la face interne des membranes vésiculaires et dans les corps protéiques en formation, structures dans lesquelles s’accumulent les protéines de réserve du grain. L’analyse par AFFFF (Asymmetrical Flow Field-Flow Fractionation) des deux lignées Hard et Soft, qui diffèrent essentiellement par l’absence du gène Pina dans la lignée Hard, a montré une corrélation entre la dureté et la taille des polymères de protéines de réserve. L’analyse protéomique des fractions albumines/globulines et amphiphiles des grains en développement a révélé une augmentation des protéines de la machinerie de repliement et de réponse au stress dans la lignée Hard, par rapport à la lignée Soft. Les deux approches méthodologiques utilisées semblent également mettre en évidence une cinétique de développement du grain raccourcie dans la lignée Hard. Ces observations suggèrent que les puroindolines interagissent avec les protéines de réserve du grain et suivent le même routage cellulaire. Elles pourraient être impliquées dans les mécanismes de repliement et d’assemblage des prolamines. / Wheat grain hardness, a major trait for endosperm texture and flour end-use properties, is strongly associated to absence or modification of puroindolines. To gain insight into biological function of those proteins in bread wheat kernel (Triticum aestivum L.), puroindolines’ subcellular localization was sought by immunocytochemistry and proteomes were analyzed at four stages of developing kernels in two near-isogenic lines for hardness, differing mainly in the absence of Pina in the Hardline. As early as the end of endosperm cellularisation, puroindolines were localized onto vesicular membranes and into protein bodies, where storage proteins accumulate. Using AFFFF (Asymmetrical Flow Field-Flow Fractionation), we observed a correlation between hardness and storage protein polymer size. Proteomic analyses of the albumin/globulin and amphiphilic fractions revealed an increase in folding and stress-related proteins in the Hard line, as compared to the Soft one. Both ultrastructural and proteomic studies suggested also that the Hard/Soft genotype affects the kinetics of kernel development. These lines of evidence imply that puroindolines interact with storage proteins and display the same routage. Puroindolines could therefore be involved in prolamines folding and assembly mechanisms.
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Analyse du protéome de l'albumen et des couches périphériques du grain de blé (Triticum aestivum L.) en développement : vers une intégration des données avec le transcriptome / Proteomic analysis of endosperm and peripheral layers during kernel development of wheat (Triticum aestivum L.) and a preliminary approach of data integration with transcriptome

Tasleem-Tahir, Ayesha 04 July 2012 (has links)
Le blé est la seconde céréale la plus produite dans le monde. Il constitue une importante source de denrées alimentaires et de beaucoup d’autres usages industriels. La compréhension des mécanismes impliqués dans le développement du grain de blé est fondamentale pour développer des blés à valeur ajoutée. La physiologie du grain de blé et les mécanismes moléculaires impliqués dans son développement nécessitent d’être mieux connus et ces connaissances pourront être très utiles pour l’amélioration du blé mais aussi des autres céréales. L’approche protéomique a été aussi utilisée dans ce contexte mais aucun travail n’avait jusqu’ici été réalisé sur la totalité des phases de développement des tissus et sur des intervalles de temps très courts. La caractérisation des changements d’expressions protéiques dans les couches périphériques du grain et de l’albumen est présentée dans cette étude. Nous avons utilisé les grains de Triticum aestivum de la variété Récital, cultivés à l’INRA de Clermont-Ferrand. Les grains ont été prélevés tous les 50°C jour (°Cj) depuis la fécondation jusqu’à la maturité sur 15 stades de développement pour les couches périphériques et sur 21 stades pour l’albumen amylacé. Pour chaque échantillon, les couches périphériques des grains ont été disséquées et les protéines totales extraites. L’analyse des protéines en électrophorèse bidimensionnelle puis par spectrométrie de masse MALDI-TOF a permis d’identifier via l’interrogation des bases de données, 207 protéines différentiellement exprimées sur 15 stades de développement (0°Cj-700°Cj). Ces protéines ont ensuite été classées en 16 classes fonctionnelles. L’analyse en cluster a révélé 5 profils d’expression au cours du temps. Parallèlement, l’albumen amylacé a été isolé des grains et les protéines métaboliques de ce tissu extraites. Après électrophorèse bidimensionnelle des protéines, 487 protéines variant significativement dans l’albumen sur l’ensemble des stades de développement (0°Cj-1006°Cj) ont été identifiées par utilisation de la LC-MS. Les protéines ont été réparties sur neuf profils d’expression et 17 fonctions biochimiques. Le protéome des couches périphériques a ensuite été comparé au protéome de l’albumen dans le but de comprendre si l’évolution des processus biochimiques diffère dans chacun de ces tissus. Au final, nous avons optimisé l’intégration des données protéomiques avec celles du transcriptome (en se focalisant sur les protéines du métabolisme carboné). Seulement 32% des profils d’expression protéome/transcriptome montrent une corrélation significative au cours du développement (152°Cj-700°Cj). Les profils d’expression des enzymes ont été comparés sur les deux niveaux. Ils devraient permettre de distinguer les processus régulés au niveau du transcriptome de ceux régulés au niveau du protéome. L’ensemble de ces données pourra être compilé dans une base de données propre de la variété Récital et utilisé comme référence dans l’étude des maladies et des stress abiotiques des tissus du grain de blé en développement. / Wheat is the second most produced cereal in the world, important for food, feed and many industrial uses. Understanding of the mechanisms involved in grain development is fundamental for developing high quality wheat. In particular, detailed knowledge of the wheat grain physiology and molecular mechanisms involved in its development would help in breeding not only of wheat but also many other cereals. A proteomic approach has been used in this context but, up to now, there had been no work on developing tissues at very short temporal distances. This thesis presents, firstly, a proteomic study to characterize protein expression changes in peripheral layers and in starchy endosperm of wheat, during kernel development. We used grains of Triticum aestivum cv Récital, cultivated at INRA, Clermont-Ferrand. Grains were harvested at each 50°Cd from fertilization to maturity at fifteen stages for peripheral layers and at twenty-one stages for starchy endosperm. After grain dissection, protein extraction and 2DE- MALDI-TOF MS and data mining, we identified 207 differentially expressed proteins at fifteen stages (0°Cd-700°Cd) of peripheral layers during kernel development. These proteins were then classed in sixteen different functional classes. HCA revealed five different expression profiles during development. Similarly after obtaining starchy endosperm from dissected grains, we performed protein extraction specific to metabolic proteins. After 2DE, 487 proteins were identified from fertilization to grain maturity (0°Cd-1006°Cd), using LC-MS and data mining. Proteins were grouped in nine different expression profiles and were classed in seventeen biochemical functions. We have constructed proteome maps of these two important grain tissues during kernel development. Further, the comparison of peripheral layers and starchy endosperm proteomic data was made, with an objective to understand whether the changes in different biochemical processes differ between these tissues.Finally, we performed an integration of our proteomic data (focusing our approach on proteins involved in carbohydrate metabolism) with that of transcriptomics. Only 32% of proteome/transcriptome expression profiles showed a significant correlation during development (from 152°Cd-700°Cd). Comparison of enzyme expression profiles with those of proteome and transcriptome would help to distinguish the processes regulated at transcriptome level and those controlled at the proteome level. This comprehensive grain development data could further help in construction of a Récital databank, which may be used as reference for studies of diseased and stressed grain tissues during development.

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