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.

Apesar de Culex quinquefasciatus ser um eficiente vetor de doenças tais como a filariose linfática, febre do Nilo Ocidental e outras várias neuroviroses, poucas pesquisas sobre sua fisiologia têm sido conduzidas. Como em todos os animais ovíparos, o desenvolvimento embrionário dos mosquitos depende da degradação dos nutrientes armazenados no ovo, sendo a catepsina B uma protease que tem sido identificada e caracterizada em vários insetos como envolvida nesta função. Neste trabalho identificamos, por espectrometria de massas, duas catepsinas B de Culex quinquefasciatus, parcialmente purificadas por autoproteólise de extrato total de ovos. Segundo a anotação de suas sequências no banco de dados específico para vetores, o VectorBase, elas são enzimas parálogas e suas sequências apresentam 77% de homologia. Denominadas neste trabalho como CatB1 e CatB2, ambas são expressas simultaneamente no corpo gorduroso de todas as fêmeas vitelogênicas de nossa colônia e sua atividade pode ser detectada nos ovários vitelogênicos, sugerindo sua origem materna. A transcrição de ambas as enzimas se inicia após o repasto sanguíneo (ARS), alcançando o pico de expressão às 36 h ARS, de forma bastante semelhante à da vitelogenina. / Despite Culex quinquefasciatus be an efficient vector of diseases such as lymphatic filariasis, West Nile fever and other various neurotrophic viruses, little research on its physiology have been conducted. As in all oviparous animals, embryonic development of mosquitoes depends on the degradation of the nutrients stored in the egg. Cathepsin B is a protease that has been identified and characterized in a number of insects as involved in this function. In this work we have identified, by mass spectrometry, two cathepsins B of Culex quinquefasciatus, partially purified by self-proteolysis of total egg extract. According to the annotation of their sequences in the specific vector database, the VectorBase, they are paralogue enzymes and their sequences have 77% homology. Named in this work as CatB1 and CatB2, both are expressed simultaneously in the fat body of all vitellogenic females of our colony and its activity can be detected in vitellogenic ovaries, suggesting a maternal origin. The transcription of both enzymes starts post blood meal (PBM), reaching their peak of expression at 36 h PBM, quite similar to vitellogenin.

Made available in DSpace on 2014-08-20T14:38:42Z (GMT). No. of bitstreams: 1 Dissertacao_Aiane_Aparecida_Catalan.pdf: 1283853 bytes, checksum: ef3c631db67b69a9bb46c36afb7dc822 (MD5) Previous issue date: 2011-02-28 / Panax ginseng, a medicinal plant known as the plant that "cure all ills" is indicated as adaptogenic, immune stimulant, restorative physical and mental health, increased resistance to exogenous stress factors, among others. The aim of this study was to evaluate the action of a commercial Panax ginseng product on performance, egg quality, biochemical, hematological, immunological and behavioral profile of hens during initial hen s laying cycle 1. The experimental design was completely randomized with five treatments which consisted in different levels of Panax ginseng (T1 control (without Panax ginseng); T2 1.9; T3 3.8; T4 5.7 and T5 7.6 mg/hen/day) in a total of 70 birds housed in 35 cages with seven replicates per treatment. The basal diets were prepared using corn and soybean meal in agreement with the nutritional values established by the breeder manual. To predict the effect of different levels of Panax ginseng on performance, egg quality, biochemical, hematological, and immunological traits the regression analysis was used. The Dunnett test was used in each Panax ginseng levels to compare to the control treatment. Ethological parameters were evaluated using chi-square analysis. Performance and egg quality were not influenced by dietary treatments, except specific gravity in the first period that was lower in 5.7 mg/hen/day levels and the eggshell weight that was higher in 7.6 mg/hen/day level in comparison with the control treatment in the fourth period. In sensorial analysis, egg yolk color alteration, but not flavor, texture and taste was observed after 30 days of utilization of Panax ginseng. No significant difference was found in hen s hematological profile in all periods evaluated. In metabolic parameters, higher level of phosphorus in hens receiving 7.6 mg/hen/day of Panax ginseng at second and third period and albumin was observed only in the last period when compared to the control group. Cholesterol level was higher in hens receiving 1.9 and 3.8 mg/hen/day of Panax ginseng in comparison with the control treatment. No significant difference among treatments was found in antibody titer after vaccination. In ethological parameters vigilant behavior was more frequent in control group, preening in the group receiving 7.6 mg/hen/day and drinking in the intermediate levels of Panax ginseng (3.8 and 5.6 mg/hen/day). The supplementation with Panax ginseng up to 7.6 mg/hen/day do not change the performance, egg quality, hematological profile and immunological status. Only small variations in the metabolic parameters and behavior frequency of the hens receiving Panax ginseng could be expected. / Panax ginseng, uma planta medicinal conhecida como a planta que cura todos os males é indicada como adaptogênica, imunoestimulante, revigorante físico e mental, aumenta a resistência a fatores de estresse exógeno, entre outros. Neste trabalho foi avaliado a ação de um produto comercial a base de Panax ginseng sob o desempenho produtivo, a qualidade dos ovos (interna, externa e sensorial), o perfil hematológico e bioquímico, parâmetros imunológicos e comportamentais de poedeiras na fase inicial de postura 1. As dietas experimentais foram fornecidas as aves durante 30 dias. O delineamento experimental foi o inteiramente casualizado com cinco tratamentos que consistiram em diferentes doses de Panax ginseng (T1 controle (sem Panax ginseng); T2 1,9 mg/ave/dia; T3 3,8 mg/ave/dia; T4 5,7 mg/ave/dia; T5 7,6 mg/ave/dia) num total de 70 aves, distribuídas em 35 gaiolas, divididas em sete repetições por tratamento. As dietas basais foram formuladas a base de milho e farelo de soja, atendendo as exigências das aves. Para predizer os efeitos das doses de Panax ginseng sobre os parâmetros produtivos, metabólicos e hematológicos foi utilizada análise de regressão polinomial. Foi utilizado o teste de Dunnett, em cada nível de inclusão do Panax ginseng, para comparação com a ração controle. Para a análise da frequência de comportamentos foi utilizado o teste de qui-quadrado. A suplementação da dieta com o produto a base de Panax ginseng não alterou as variáveis de desempenho. As variáveis de qualidade de ovos não foram afetadas pela inclusão de Panax ginseng, exceto a gravidade específica no primeiro período que foi menor na dose 5,7 mg/ave/dia e o peso da casca que foi significativamente maior na dose de 7,6 mg/ave/dia em comparação ao tratamento controle no quarto período de avaliação. Na análise sensorial foi observada alteração na cor da gema dos ovos após 30 dias de utilização do Panax ginseng, mas não no sabor, textura e aroma. No perfil hematológico das poedeiras não foram observadas diferenças significativas entre os tratamentos em nenhuma das fases. No perfil metabólico foram observadas maiores níveis de fósforo nas aves que receberam 7,6 mg/ave/dia de ginseng em comparação com o grupo controle nos períodos dois e três de avaliação e de albumina somente neste último período. Os níveis de colesterol foram maiores nas aves recebendo dosagens de 1,9 e 3,8 mg/ave/dia de Panax ginseng em relação ao grupo controle. Não houve diferença entre os tratamentos para os títulos de anticorpos após a inoculação da vacina. Nas variáveis etológicas os comportamentos de vigiar foram mais frequentes no grupo controle, o comportamento de higiene no grupo com a maior dose de Panax ginseng (7,6mg/ave/dia) e o comportamento de beber água nas doses intermediárias (3,8 e 5,6 mg/ave/dia). A suplementação com Panax ginseng até 7,6 mg/ave/dia não altera o desempenho, a qualidade dos ovos, o perfil hematológico e status imunológico. Apenas pequenas variações no perfil metabólico e na freqüência de alguns comportamentos podem ser esperadas.

Made available in DSpace on 2014-08-20T14:38:49Z (GMT). No. of bitstreams: 1 Dissertacao_ Juliana_ Klug_ Nunes.pdf: 4118597 bytes, checksum: 3c27dbdcf97e2cfc50cbf822af01cb11 (MD5) Previous issue date: 200-11-20 / This study aimed to evaluate the effect of graded levels (0, 1, 2 and 3%) of dietary inclusion of an yeast-extract product2 on internal and external quality of eggs and on performance of layers. A total of 240-Hy Line W36 layers (47 to 75 weeks of age) were allocated in 60 cages (4 birds per cage), divided into 15 cages per treatment. Feed intake, body weight, egg production, egg weight, egg mass, feed conversion (per dozen), feed conversion (per mass), specific gravity, eggshell weight and thickness, albumen height, Haugh units and yolk and albumen weights were evaluated. Data were subjected to ANOVA and polynomial regression. A P<0.05 was required for statements of significance. Results indicated that addition of 1,5% NuPro® resulted in better eggshell quality. The remaining variables were not statistically influenced by dietary treatments. / Esta pesquisa teve por objetivo avaliar o efeito dos níveis crescentes (0, 1, 2 e 3%) de suplementação dietética do extrato de levedura1 sobre o desempenho produtivo e a qualidade externa e interna de ovos. Um total de 240 poedeiras Hy Line W36, no período de 47 a 75 semanas de idade, foram distribuídas em 60 gaiolas, sendo quatro aves por gaiola, divididas em 15 repetições por tratamento. As características avaliadas foram consumo de ração, peso corporal produção de ovos, peso do ovo, massa de ovo, conversões alimentares por dúzia e por massa de ovo, gravidade específica, peso e espessura da casca, altura do albúmen, unidade Haugh e pesos da gema e do albúmen. Os dados foram submetidos à análise de variação e regressão polinomial. O valor de P<0,05 foi estabelecido para a determinação de significância. Os resultados indicaram que a adição de 1,5% do extrato de levedura resultou melhor qualidade de casca dos ovos. As demais variáveis não foram influenciadas estatisticamente pelos tratamentos.

Two experiments were conduced to the effect of relationship between calcium and phosphorus available (8/1; 11/1 and 14/1) in diets based on maize and soybean meal. Each experiment used 144 brown egg layer (UFSM V and UFSM P strain) from 28Th to 36Th weeks of age. The evaluated parameters had been body weight, fed intake, fed efficiency, egg production, albumen height, eggs mass, specific gravity of eggs, Haugh Unit and percentage of calcium, phosphorus and ash of the tibia. Each experiment was in a factorial design 3x2, with tree relationship between calcium and phosphorus available (8/1; 11/1 and 14/1) and two phytase levels (0 and 300FTU/kg), with six replicates with four layers hens each. The external quality of eggs based on specific gravity, were positively affected (P<0.026), by interaction between calcium and phosphorus available relationship and phytase, in the last studied period, of UFSM-P strain, when the specific gravity improved with the increase of the calcium and phosphorus available relations and phytase. The productive parameters and the internal quality of eggs were not affected by the studied factors, however, the bone quality, based on ash, calcium and phosphorus in the tibias, were lower when dietary calcium and phytase levels were decreased. / Foram conduzidos dois experimentos para determinar os efeitos das diferentes relações cálcio:fósforo disponível e fitase em dietas a base de milho e farelo de soja. Um experimento utilizou a linhagem UFSM-V e outro a linhagem UFSM-P, que são linhagens de poedeiras de ovos de casaca marrom. Cada experimento utilizou 144 poedeiras da 28ª a 36ª semana de idade. Os parâmetros avaliados foram: peso corporal, consumo de ração, conversão alimentar, produção de ovos, altura de albúmen, massa e gravidade específica dos ovos, Unidade Haugh e teor de cálcio, fósforo e cinzas da tíbia. Cada experimento utilizou um delineamento em esquema fatorial 3x2 onde 3 foram as diferentes relações cálcio: fósforo disponível (8/1; 11/1; 14/1) e 2 os níveis de fitase (0 e 300FTU/kg). A qualidade externa dos ovos, avaliada pela gravidade específica, foi significativamente influenciada (P<0,026), pela interação entre as relações de Ca:Pd e fitase, no último período estudado, com a linhagem UFSM-P, elevando a gravidade específica com o aumento das relações Ca:Pd e fitase. Os parâmetros produtivos e a qualidade interna dos ovos não foram afetados pelos fatores estudados, porém, a qualidade óssea, avaliada pelo teor de cinzas, cálcio e fósforo nas tíbias, foi significativamente influenciada pelo decréscimo das relações Ca:Pd e de fitase na dieta.

This thesis deals with important factors that affect the temporal organization of emergence and early survival of Baltic salmon (Salmo salar L.). The study population was obtained from the Norrfors hatchery (63°50'N,20°05'E), Umeälven (Ume river) in Northern Sweden. The main objectives of the thesis has been to study; a: the effect of female and egg characteristics on embryonic survival, b: the effect of egg size, temperature and photoperiod on the emergence pattern and c: the impact of early or late emergence on survival in relation to predation and limited territorial space. The main results are summarized as follows: (1) Fecundity and egg size increased with increasing weight of females. No effect of female size were found on egg colour. Longer impoundment and later stripping increase egg colour. Egg mortality was not correlated with egg colour. Stripping date was found to have the strongest effect on mortality. (2) Egg size had no effect on the timing of emergence but fry of different egg size emerged synchronously. Fry from large eggs left the gravel as heavier fry and with a larger proportion of yolk left compared to fry from small eggs. (3) The number of days and number of degree days from hatching to 50% emergence decreased exponentially with increasing temperature. Synchronization of emergence increased with increasing temperature. Fry emerged with more yolk at 12 °C compared to 6 °C. (4) Eggs kept in a LD 16:8 light regime hatched mainly during the light period, while eggs kept in constant darkness hatched continously over a 24 hour period. Alevins kept at different light regimes (light&gt;4h) from hatching until emergence left the gravel during the dark period. Daylength had no effect on the annual onset of emergence. (5) In a laboratory stream channel, predator presence at emergence increased mortality especially in early emerging fry. If the predator was introduced after completed emergence high mortality was noted among late emerging fry. The presence of fish predators and a limited territorial space for fry seemed to make early and late emergence hazardous and to favour a "peak" emergence. In the presence of a predator the fry changed their behaviour by reducing their swimming activity. / digitalisering@umu.se

La compréhension du lien entre alimentation et santé est un challenge majeur pour les domaines des sciences de l'aliment et de la nutrition. L'effet d'un aliment sur la santé étant conditionné par son passage et sa déstructuration dans le tube digestif, explorer cette question implique donc nécessairement de progresser dans la compréhension du processus de digestion. L'œuf est un produit apprécié dans le monde entier et compte parmi les aliments les plus nutritifs pour l'Homme. La fraction blanc d'œuf, solution aqueuse de protéines, est un ovoproduit très utilisé par l'industrie alimentaire en raison de ses propriétés fonctionnelles et nutritionnelles. De plus, la possibilité de générer des structures d'aliment très différentes selon les modalités du traitement technologique, sans avoir à en modifier la composition, fait du blanc d'œuf un aliment modèle réaliste particulièrement intéressant. Cette étude a été menée dans l'objectif d'étudier l'impact des caractéristiques structurales de matrices protéiques agrégées et gélifiées sur leur déstructuration au cours de la digestion. Un modèle in vitro de digestion gastro-intestinale, permettant un suivi temporel, a été combiné avec un modèle in vivo (porcin), plus proche de la réalité physiologique et permettant un suivi spatio-temporel de la digestion. Dans le cas du blanc d'œuf, la structuration de la matrice protéique s'est avérée avoir une influence non seulement sur les aspects quantitatifs de la digestion comme le degré d'hydrolyse des protéines, mais également sur les aspects qualitatifs comme la nature des peptides libérés. De même in vivo, les niveaux de bioaccessibilité pourraient être impactés par les différences relatives aux caractéristiques structurales des matrices gélifiées. A l'échelle moléculaire, cette étude suggère ainsi que les changements structuraux induits par les traitements thermiques, variables selon les conditions du milieu, rendent accessibles aux enzymes digestives des zones variables des protéines. A l'échelle micro- et macroscopique, les caractéristiques structurales des gels impactent également le déroulement de la digestion. / Understanding the relationship between health and diet is a major challenge in Food Science and Nutrition. As the impact of a food product on health depends on its journey and breakdown in the gastrointestinal tract, exploring this question necessarily implies increasing our knowledge of the food digestion process. Eggs are popular worldwide and are among the most nutritious foods for humans. The egg white fraction, an aqueous protein solution, is an egg product widely used in the food industry because of its unique functional and nutritional properties. In addition, the ability to generate very different food structures depending on the technological process without modifying its composition, makes egg white a very interesting and realistic food model. The aim of the study was to investigate the impact of structural characteristics of aggregated and gelled protein matrices on their breakdown during digestion. An in vitro model of gastrointestinal digestion, enabling temporal tracking, was combined with an in vivo model (pig), closer to physiological reality and enabling spatio-temporal mapping of digestion. For egg white, the structural characteristics of the protein matrix were found to have an influence not only on the quantitative aspects of protein digestion such as the degree of hydrolysis, but also on the qualitative aspects such as the nature of the peptides released. Similarly, the in vivo bioaccessibility levels could be impacted by differences relating to the structural characteristics of the gelled matrices. At the molecular scale, this study suggests that the structural changes induced by heat treatments, depending on physicochemical conditions, render a number of protein regions accessible to digestive enzymes. At the micro- and macroscopic scale, the structural characteristics of the gels also impact the digestion process.

This research project consisted of five experiments. The main objective of this study was to determine the effects of restricted feeding and season on growth, carcass characteristics, meat chemical composition, reproduction and egg laying performance of Koekoek chickens. Feed restriction lowered the body weight, weight gain, feed intake and improved the feed conversion efficiency during the rearing phase. During the laying phase, chickens that were in the RA treatment had higher body weights, weight gains and lower FCR. Chickens that were reared in summer had a higher body weight, weight gain and FCR, while total feed intake and mortality rates were high in winter. Feed restriction reduced the slaughter weight, defeathered weight, dressed weight, skin weight, breast muscle weight, shank width, chest width and heart girth during the rearing phase. The intestine, liver and abdominal fat pad weights were higher in chickens that were fed ad libitum. Chickens that were reared in summer had higher shank width, slaughter weight, defeathered weight, chest width, heart girth, breast muscle weight, skin weight, abdominal fat pad weight, intestine weight, liver weight and the relative skin percentage at the age of 18 weeks. During the laying phase, abdominal fat pad weight, abdominal fat pad percentage, intestine percentage, liver weight, gizzard weight and gizzard percentage were higher in the ad libitum fed chickens. Unrestricted feeding during the rearing phase increased the development of combs, wattles, pubic bones, ovaries and oviducts more than restricted feeding while at the age of 32 weeks, enhanced growth of the reproductive organs was seen in chickens that were fed ad libitum only during the laying phase (RA). The cold winter conditions hindered the growth of the combs, wattles, pubic bones, oviducts and ovaries. Restricted feeding during the laying phase reduced the laying percentage, egg weights and improved the hatching percentage. Ad libitum feeding during the rearing phase resulted in the attainment of puberty at an earlier age in chickens. Chickens that were produced in summer reached puberty first as well as 20%, 50% and 80% egg production, and had a higher average laying percentage and egg weights. / Thesis (PhD)--University of Pretoria, 2012. / Animal and Wildlife Sciences / unrestricted

Ovos e seus produtos derivados têm sido envolvidos em surtos de doenças transmitidas por alimentos devido à contaminação por Salmonella Enteritidis. A irradiação é uma das tecnologias existentes para a conservação de alimentos que poderia minimizar esse problema. O objetivo desta pesquisa foi determinar o efeito da irradiação sobre ovo líquido, ovo congelado, ovo em pó, gema em pó e clara em pó contaminados com Salmonella Enteritidis. As amostras de ovo líquido, clara em pó e gema em pó, inoculadas com S. Enteritidis, foram expostas a doses de 0,5; 1,0; 1,5; 2,0; 2,5; 3,0 kGy e as de ovo congelado e ovo em pó foram irradiadas com 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 3,5 e 4,0 kGy. Amostras não inoculadas e irradiadas e amostras não inoculadas e não irradiadas dos diferentes tipos de ovos foram testadas quanto ao odor cru, odor e sabor cozidos, cor, viscosidade e oxidação lipídica. Doses de 2,0; 3,0; 3,5; 3,0 e 3,5 kGy reduziram em 5 ciclos log a população de S. Enteritidis em ovo líquido, ovo congelado gema em pó, clara em pó e ovo em pó, respectivamente, com alterações levemente perceptíveis pelo painel de degustadores. A cor não sofreu alteração ou sofreu alteração moderada. As alterações mais intensas foram verificadas para viscosidade dos produtos em pó e para o aumento da concentração de malonaldeído em gema e ovo em pó. Portanto, o emprego da irradiação é factível para ovo líquido e congelado. Para os em pó, porém, deve ser ressaltado que a aplicação do processo está condicionada ao uso final do produto ao quais serão adicionados devido à alteração na viscosidade. / Eggs and their products have been incriminated in foodborne disease outbreaks due to Salmonella Enteritidis contamination. Irradiation is a food preservation technology that could be applied to minimize the problem. The aim of this study was to determine the effect of irradiation in liquid and frozen egg as well as in powdered egg, egg yolk and egg white spiked with Salmonella Enteritidis. Spiked samples of liquid egg, egg white and egg yolk were exposed to 0,5; 1,0; 1,5; 2,0; 2,5; 3,0 kGy and spiked samples of frozen and powdered egg were exposed to 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 3,5 e 4,0 kGy. Raw odour, cooked odour and taste of non inoculated and irradiated samples and non irradiated samples of egg and egg products were analysed by a trained panel. Viscosity and lipid oxidation (malonaldheyd concentration) were also determined. Doses of 2,0; 3,0; 3,5; 3,0 e 3,5 kGy reduced in 5 log the population of S. Enteritidis in liquid and frozen egg, powdered egg yolk, egg white and egg, respectively, with moderate alterations in relation to non irradiated samples detected by the trained panel. Viscosity and lipid oxidation in the powdered products, however, showed more intense alterations. Therefore, irradiation can be considered a feasible process for liquid and frozen egg while when applied to powdered products it should be considered the type of food product to which they will be added due to alterations in viscosity.

Made available in DSpace on 2016-01-26T18:55:45Z (GMT). No. of bitstreams: 1 Dissertacao Luciana Puga.pdf: 175865 bytes, checksum: ab5d65c8bd35ac9dbd8f2cc6697281da (MD5) Previous issue date: 2008-08-29 / The purpose of this study was to standardize a flotation technique for the recovery of Toxocara canis eggs from soil, comparing different steps. The tests were done under standardized conditions on 1 g of previously sterilized soil samples contaminated experimentally with 200 eggs of T. canis. The following variables were evaluated in serial steps: sieving; type of wash; time of stirring; resuspention of sediment; solution flotation. Centrifuge-flotation in sodium nitrate (d= 1,20) was adopted as an initial technique, using Tween 80 (0.2%) and decinormal sodium hydroxide as solutions for washing the samples. Ten tests were made to compare the variables, using counting in triplicate. The sieving of the material reduced the recovery of eggs in a significant difference (p<0.001) and the number of eggs recovered were higher when the sediment was resuspended (p<0.05). After standardization, flotation solutions sodium chloride, zinc sulphate, sodium dichromate, magnesium sulphate, and sodium nitrate (d= 1,20) were compared. There was a significant difference between zinc sulphate and sodium chloride (p<0.05). In conclusion, the chance of recovering T. canis eggs from samples using flotation solutions can be increased by using resuspended sediment. On the other hand, the sieving procedure can drastically reduce the number of eggs. / O objetivo do estudo foi padronizar uma técnica para recuperação de ovos de ascarídeos (Toxocara canis) em solo, com a comparação de diferentes etapas. Amostras de solo foram previamente esterilizadas e divididas em alíquotas de um grama, sendo contaminadas com 200 ovos. Após a contaminação, foram comparadas, em etapas seriadas, as variáveis: filtragem, tipo de lavagem e re-suspensão do material. Como ponto de partida para comparação, utilizou-se uma técnica com lavagem de solo em Tween 80 (0,2%) e solução de hidróxido de sódio 0,1N; re-suspensão; e centrífugo-flutuação em solução de nitrato de sódio (d=1.20). Os ovos recuperados foram contados com 10 repetições, com três leituras para cada repetição. A filtragem reduziu significativamente a recuperação de ovos em relação ao material não filtrado (p<0,001), enquanto o número de ovos foi significativamente maior quando utilizada a re-suspensão do material (p<0,05). Após padronização, comparou-se as soluções de cloreto de sódio, dicromato de sódio, nitrato de sódio, sulfato de zinco, sulfato de magnésio, havendo diferença entre sulfato de zinco e cloreto de sódio (p<0,001). Dessa forma, as chances de recuperação de ovos de T. canis podem ser ampliadas pelo re-suspensão do sedimento, enquanto que a filtragem reduz consideravelmente o número de ovos.