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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.
1

REGULATION TRANSCRIPTIONNELLE DU PROMOTEUR HMWG-DX5 DE BLE DANS L'ALBUMEN DE MAÏS ET CREATION DE PROMOTEURS CHIMERIQUES.

Norre, Frédéric 25 October 2002 (has links) (PDF)
La région promotrice proximale du gène Glu-1D1 de gluténine de haut poids moléculaire de blé (PrHMWG-Dx5) porte une boîte albumen bifactorielle atypique qui comprend un motif G " like " (5'-TTACGTGG-3') situé en amont d'une boîte prolamine (Pb1, 5'-TGCAAAG-3'). Les tests d'expression transitoire dans l'albumen de maïs indiquent que le fragment promoteur minimal contenant au moins la boîte G " like " est nécessaire et suffisant pour une activité maximale de PrHMWG-Dx5. Dans le maïs transgénique, nous avons montré que la séquence de 89 pb qui contient la boîte albumen bifactorielle se comporte comme une unité cis-activatrice fonctionnelle. Sa répétition en tandem direct confère un effet activateur additif puissant spécifique de l'albumen. En contraste, l'association des séquences activatrices as-1 et as-2 du promoteur 35S du CaMV avec des séquences promotrices dérivées de PrHMWG-Dx5 dérégule son activité dans les plants de maïs et de tabac. Par la technique de retard de migration, nous avons démontré que la boîte G " like " peut fixer deux groupes de protéines qui ont respectivement la même affinité de liaison à l'ADN que les facteurs de transcription de la famille Opaque-2 et de la famille ASF-1. Nos résultats nous conduisent à proposer un modèle hypothétique qui repose sur une dualité fonctionnelle de la boîte G " like " dans l'albumen des céréales, et suggère son implication potentielle alternativement dans la synthèse des protéines de réserve et dans la réponse de défense de la plante.
2

Effects of Surface Properties on Adhesion of Protein to Biomaterials

Feng, Fangzhou 2010 August 1900 (has links)
This thesis research investigates the adhesion mechanisms of protein molecules to surfaces of biomaterials. New understanding in such adhesion mechanisms will lead to materials design and surface engineering in order to extend the lifespan of implants. The present research evaluates and analyzes the adhesive strength of proteins on pure High Density Polyethylene (HDPE), Single Wall Carbon Nanotube (SWCNT) enhanced HDPE composites, Ti-C:H coating and Ti6Al4V alloys (grade 2). The adhesive strength was studied through fluid shear stress and the interactions between the fluid and material surfaces. The adhesive strength of protein molecules was measured through the critical shear strength that resulted through the fluid shear stress. The effects of surface and material properties, such as roughness, topography, contact angle, surface conductivity, and concentration of carbon nanotubes on adhesion were analyzed. Research results showed that the surface roughness dominated the adhesion. Protein was sensitive to micro-scale surface roughness and especially favored the nano-porous surface feature. Results indicated that the unpurified SWCNTs influenced crystallization of HDPE and resulted in a nano-porous structure, which enhanced the adhesion of the protein onto a surface. Titanium hydrocarbon coating on silicon substrate also had a porous topography which enhanced its adhesion with protein, making it superior to Ti6Al4V.
3

Modulation de l'immunité innée moléculaire de l'oeuf / Modulating the innate molecular immunity of the egg

Bedrani, Larbi 11 April 2013 (has links)
L’œuf est un aliment riche en divers composés dont de nombreuses molécules antimicrobiennes qui sont les effectrices de son système de défense moléculaire innée et complètent l’action des immunoglobulines (IgYs) afin de protéger l’embryon. La composition en IgYs de l’œuf est sous la dépendance notamment des stimulations microbiennes de la poule. L’objectif de notre travail a été d’évaluer l’influence de ces mêmes stimulations sur le système de défense moléculaire innée du blanc d’œuf. Nous avons exploré cette hypothèse en utilisant deux approches expérimentales. La première était basée sur la comparaison de l’activité antibactérienne des blancs d’œufs de poules axéniques, de poules exemptes d’organismes pathogènes spécifiques (EOPS), et de poules conventionnelles. La seconde approche a testé les effets de deux types d’inductions du système immunitaire chez la poule: injection d’un immunostimulant, le lipopolysaccharide bactérien (LPS) et administration oral de souches vaccinales atténuées (virale, bactérienne et parasitaire). Nos résultats montrent que l’activité antibactérienne du blanc d’œuf est augmentée en fonction de la charge microbienne du milieu de vie de la poule, après stimulation de celle-ci par voie intraveineuse avec du LPS ou suite à la vaccination avec des souches atténuées virale ou bactérienne. Néanmoins cette augmentation est modérée de par son amplitude et son spectre antibactérien. Ces résultats suggèrent que les poules peuvent renforcer modérément l’activité antimicrobienne du blanc d’œuf en réponse à des stimuli microbiens de leur milieu et anticiper ainsi les besoins de l’embryon en termes de protection. / The egg is a balanced source of different nutrients and contains a myriad of antibacterial peptides/proteins that ensure its chemical protection. These molecules are a part of its innate molecular defense and, in addition to the maternal immunoglobulins IgY, contribute to the protection of the forming embryo whose development occurs ex utero. It is well documented that yolk immunoglobulin deposition is induced by the environmental microbiome of the hen but no such evidence is available for antimicrobial peptides/proteins. Therefore the aim of this thesis was to assess whether the hen has the ability to stimulate the innate molecular immunity of the egg white when facing a higher environmental microbial load (commensal or pathogenic). To address these questions, we developed two main experimental approaches; the first assessed the impact of the hen environmental microbial load through the comparison of three groups of hens with different immune status:-Germ free, -Specific pathogen free (SPF), and -conventional. The second approach explored the effect of different types of immune stimulation in hens: non-infectious stimulation (systemic injection of bacterial lipopolysaccharide (LPS)); immune stimulation using attenuated live vaccines (Infectious bronchitis virus vaccine, Salmonella enterica Enteritidis vaccine and a complex of Eimeria vaccine). Our results show that the activity of egg white is increased in response to higher microbial environmental charge, after LPS systemic stimulation or after vaccinating hens with live attenuated viral and bacterial strains. However this response is moderate both in its amplitude and microbial spectrum. Altogether, it appears that hens when subjected to immune stimuli, have the ability to reinforce moderately the antibacterial activity of the egg white as an attempt to anticipate the need of protection of their embryos.
4

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...
5

Contribution à l’étude du contrôle transcriptionnel de la maturation de la graine d’Arabidopsis / Study of the transcriptional regulation of Arabidopsis seed maturation

Barthole, Guillaume 18 September 2013 (has links)
Chez la plante modèle Arabidopsis, le processus de maturation de la graine et, en particulier, l’accumulation de composés de réserves (huile et protéines de réserve) sont étudiés depuis de nombreuses années. Si les voies de biosynthèse conduisant à l’accumulation de tels composés sont bien décrites, leur régulation est encore largement méconnue. Mon travail de thèse s’inscrit dans un projet de recherche dont le but est d’identifier de nouveaux régulateurs transcriptionnels de la maturation de la graine d’Arabidopsis. Après avoir réalisé une étude comparative du processus de maturation chez les deux zygotes de la graine, embryon et albumen, nous avons caractérisé un facteur de transcription appelé MYB118, exprimé spécifiquement dans l’albumen et potentiellement impliqué dans la régulation du processus de maturation. Son patron d’expression, finement caractérisé, montre un pic d’accumulation d’ARNm en début de maturation de la graine, plus spécifiquement dans l’albumen. Des études menées sur des lignées mutantes ou surexprimant LEAFY COTYELDON2 (LEC2) révèlent que l’expression de MYB118 est activée par ce régulateur maître de la maturation de la graine. Une analyse biochimique de graines myb118 montre que le contenu en huile et en protéines de réserve est doublé dans l’albumen et réduit dans l’embryon de ce mutant par comparaison aux graines sauvages. Finalement, une analyse transcriptomique effectuée sur des graines myb118 a permis d’identifier des cibles putatives dont la dérégulation pourrait expliquer le phénotype : MYB118 semble être un répresseur de l’accumulation de composés de réserve dans l’albumen. Comme la famille de facteurs de transcription à laquelle appartient MYB118 comprend de nombreux membres, nous nous sommes intéressés au patron d’expression et au rôle de ses paralogues les plus proches. L’un d’entre eux, appelé MYB115, est exprimé spécifiquement dans l’albumen chalazal et semble avoir une fonction partiellement redondante à celle de MYB118. / In the model plant Arabidopsis thaliana, seed maturation and more especially the accumulation of storage compounds such as oil and seed storage proteins (SSP) have been widely studied. Although the biosynthetic networks underlying the accumulation of such compounds are now well described, regulation of these pathways remains poorly understood. My Ph.D. project is a part of a research program aimed at identifying new transcriptional regulators of seed maturation in Arabidopsis. After a comparative analysis of maturation processes in the two zygotic tissues of the seed, namely the embryo and the endosperm, we have characterized MYB118, an endosperm-specific transcription factor, putatively involved in the regulation of this maturation process. A fine and comprehensive characterization of its expression pattern showed a peak of expression at the onset of the maturation phase in the endosperm. Expression studies carried out in LEAFY COTYLEDON2 (LEC2) mutant and over-expressing lines demonstrated that MYB118 expression is positively regulated by this master regulator. Biochemical analysis of myb118 seeds showed that oil and SSP contents were doubled in the endosperm fraction and decreased in the embryo of this mutant compared to the wild type. A transcriptomic analysis of myb118 mutant seeds point out some putative targets, the misregulation of which could explain this phenotype: MYB118 seems to be a repressor of storage compounds accumulation in the endosperm.Since MYB118 belongs to the broad family of MYB transcription factors, we investigated the expression pattern and the role of its closest paralogs. One of them, called MYB115 is expressed specifically in the chalazal endosperm and seems to have partially redundant functions with MYB118.
6

A functional and genetic analysis of novel signaling molecules regulating embryo surface formation in Arabidopsis thaliana / Analyse fonctionnelle et génétique de nouvelles molécules de signalisation impliquées dans la régulation de la formation de la surface de l’embryon d’Arabidopsis thaliana

Moussu, Steven 16 December 2016 (has links)
Le développement de la graine est une étape cruciale du cycle de vie des Angiospermes. La graine est composée de trois compartiments : (1) Le tégument, assurant un rôle protecteur, (2) l’albumen, qui a un rôle principalement nourricier pour (3) l’embryon, qui donnera la future plante. Ainsi, ces trois tissus se développent de concert pour former une graine viable. Une telle coordination présuppose que les différents compartiments communiquent entre eux. Dans ce contexte, j’ai étudié les gènes impliqués dans la formation de la cuticule embryonnaire, une structure hydrophobe recouvrant la plante et essentielle pour limiter les pertes d’eau, assurant ainsi sa survie. Au début de ma thèse, différents gènes étaient déjà connus, certains spécifiques de l’embryon, et d’autres spécifiques de l’albumen, renforçant l’idée de l’existence d’une communication moléculaire entre les deux tissus. Côté albumen, le facteur de transcription ZOU contrôle l’expression d’ALE1, une protéase. Côté embryon, deux récepteurs, GSO1 et GSO2, sont impliqués. L’étude de l’interaction génétique de ces différents gènes a permis de prouver leur appartenance à la même voie de signalisation. L’identité de ces gènes nous a amené à supposer l’existence d’un ou plusieurs peptides agissant comme messagers entre l’embryon et l’albumen. Ainsi, mes travaux de thèse ont permis de caractériser de nouveaux gènes impliqués dans ce processus, ainsi que certaines propriétés de la cuticule. Le principal est CERBERUS, dont l’expression est contrôlée par ZOU, un peptide sécrété par l’albumen qui est nécessaire pour la mise en place d’une cuticule fonctionnelle et la mise en place d’une structure non encore décrite à ce jour, la gaine embryonnaire. Un nouveau rôle pour GSO1 et GSO2 a aussi été démontré. Des résultats préliminaires suggèrent que TPST, une enzyme impliquées dans la sulfation des peptides, est impliquée dans la voie de signalisation étudiée. Enfin, mes travaux ont identifiés un autre gène, FRIABLE1, qui est aussi essentiel à la mise en place de la cuticule et joue dans la même voie de signalisation. Les découvertes associées à mes travaux de thèse ont permis de compléter et d’approfondir les connaissances sur les gènes impliqués dans la formation de la surface de l’embryon chez Arabidopsis. / Seed development is a crucial step in Angiosperms life cycle. The seed is composed of three distinct compartments: (1) The testa, ensuring a protective function, (2) the endosperm, which plays a key nutritive role supporting (3) the embryo, the fate of which is to become the future plant. These three tissues develop concomitantly to form a viable seed. Such developmental coordination necessitates the involvement of communication between the compartments. In this context, I have studied genes involved in the establishment of the embryonic cuticle, a hydrophobic structure that surrounds the embryo, plays an essential post-germination function in regulating water loss and is thus critical for plant survival. At the beginning of my PhD, several proteins were known to be involved in the process of cuticle establishment, some of which were expressed in the endosperm and others in the embryo, hinting at the existence of molecular communication between the two tissues. On the endosperm side, the transcription factor ZOU controls the expression of ALE1, a subtilisin-like serine protease. On the embryo side, two receptors, GSO1 and GSO2, are involved. Genetic interaction between the genes encoding these proteins had confirmed their involvement the same signalling pathway. The molecular identities of these proteins led us to propose the existence of one or more unidentified peptides acting as messengers between the embryo and the endosperm. My research has allowed the characterization of novel proteins involved in the process of embryonic surface formation. The principal subject of my research has been CERBERUS, a peptide produced in the endosperm, the expression of which is controlled by ZOU, and which is necessary both for the formation of an intact embryonic cuticle and the production of a previously uncharacterised structure, the embryo sheath. I have demonstrated novel roles for GSO1 and GSO2 in embryo sheath deposition. Furthermore, I have generated preliminary data suggesting that a protein involved in peptide sulfation, TPST, is involved in the GSO1 GSO2 signalling pathway. Finally, I have shown that another protein involved in posttranslational protein modification, FRIABLE1 is involved in this same pathway. My results have advanced knowledge of the molecular mechanisms controlling embryonic surface formation in Arabidopsis.
7

Análise proteômica dos ovos de codorna não fertilizados em diferentes tempos e temperaturas de estocagem / Proteomic analysis of quail eggs unfertilized at different times and storage temperatures

Adriano Aquino 12 June 2015 (has links)
O uso de codornas japonesas (Coturnix coturnix japonica) como modelo animal para estudos relacionados a indústria avícola está crescente em decorrência do aumento no consumo de carne e ovos. O ovo possui várias aplicações e a sua funcionalidade está correlacionada com a composição química e, mais especificamente, com seu alto valor proteico. Contudo, o ovo é um alimento altamente perecível, pois pode perder sua qualidade rapidamente entre o período de estocagem e consumo. A qualidade do ovo pode ser afetada por condições ambientais como tempo e temperatura de estocagem. Parâmetros convencionais como pH, massa e a unidade Haugh são usados para a avaliação da qualidade do ovo. Além disso, técnicas analíticas podem ser utilizadas para a avaliação de qualidade em diversas matrizes alimentares. Assim, o presente trabalho tem como objetivos a avaliação e identificação de proteínas presentes em ovos de codorna japonesa submetidos a diferentes tempos e temperaturas de estocagem empregando técnicas eletroforéticas e espectrometria de massas, além de, ferramentas estatísticas. Durante estocagem à 0-21 dias, observou um aumento no pH, diminuição na massa do ovo e uma mudança significativa no proteoma das amostras nos períodos de 14 a 21 dias. Além disso, os resultados de análise de componentes principais (PCA) demostraram a influência da temperatura pela formação de 4 grupos independentes para amostras de albúmen e 3 grupos para as amostras de plasma e fração granular, respectivamente. Para o plasma, as amostras estocadas à 25 °C e controle se agruparam. Já para a fração granular, o agrupamento ocorreu entre as amostras estocadas a 25 °C com a 37 °C, demonstrando similaridade entre si. As proteínas com os níveis significativamente (p <0.05) alterados durante a estocagem pertencem as famílias serpina (ovalbumina), transferrina (ovotransferrina), inibidores Kazal tipo de protease (ovoinibidor). Para a ovotransferrina, proteína encontrada em todas as amostras foi observado a formação de isoformas no albúmen, plasma e fração granular nas amostras estocadas a 37 °C, sendo um bom indicador de controle de qualidade. Por fim, para as amostras de albúmen fracionadas por OFFGEL e analisadas por 1D-PAGE foi observado a formação de isoformas tanto para a ovalbumina quanto para a ovotransferrina bem como a degradação de ovoinibidor nas amostras estocadas por 21 dias a 37 °C, fatos que podem estar associados ao desbaste. Esses eventos afirmam a influência do tempo e temperatura de estocagem na qualidade do ovo de codorna. / The use of Japanese quail (Coturnix coturnix japonica) as animal model for studies related to the poultry industry is becoming more common due to the increased consumption of meat and eggs. The egg has a variety of applications and its functionality is correlated to the chemical composition and, more specifically, its high protein value. However, the egg is a highly perishable food, and it can lose its quality between the period of storage and consumption. The egg quality can be affected by environmental conditions such as storage time and temperature. Conventional parameters such as pH and Haugh unit mass are used for egg quality assessment. Furthermore, analytical techniques can be used for quality assessment in various food matrices. This study aims to review and to identify proteins present in Japanese quail eggs submitted at different times and storage temperatures using electrophoretic techniques and mass spectrometry techniques, as well as statistical tools. During storage at 0-21 days, observed an increase in pH, decrease in egg mass and a significant change in the proteome of samples during the 14 to 21 day period. Moreover, the principal component analysis results (PCA) have shown the influence of temperature because of the formation of the four groups to albumin samples and three groups for the plasma and granules fraction samples, respectively. In plasma, the samples stored at 25 ° C and clustered control. As for the granule fraction pooling occurred between samples stored at 25 ° C to 37 ° C, showing similarities among them. The proteins with significant levels (p <0.05) of change during the storage belong to serpin family (albumin), transferrin (ovotransferrin), Kazal type protease inhibitors (ovoinhibitor). Ovotransferrin, a protein isoform found in albumin, plasma and granules fraction samples and was observed the formation of more isoforms in samples stored at 37 ° C, a good to quality control lost indicator. Finally, for the albumen samples that were fractionated by OFFGEL and analyzed by 1D-PAGE, the formation of both isoforms to ovalbumin was observed as well as ovotransferrin and ovoinhibitor degradation in samples stored for 21 days at 37 ° C that can be associated to thinning. These events affirm the influence of time and storage temperature on quail egg quality.
8

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.
9

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.
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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

Silva, Mayra Fernanda Rizzo 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.

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