999 resultados para perigos alimentares


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The food chain theory predict that presence of omnivory prevent the trophic cascade and could be a strong stabilizing factor over resource and consumer community dynamics, and that the nutrient enrichment destabilize populations dynamics. Most of the freshwater tropical reservoirs are eutrophic, and strategies that seek improve the water quality through the control of phytoplankton biomass and nutrient input, become essential for the improvement and preservation of water quality. The aim of this study was test the zooplanktivory (when larvae) and omnivory (when young and adult) effects of Nile Tilapia over the structure and dynamics of plankton communities, in addition or absence of nutrients enrichment. For this, one field experiment was performed with a factorial design 2x3 resulting in six treatments: control, without fish and nutrient (C); with omnivorous fish (O); with zooplanktivorous fish (Z); without fish and with enrichment of nutrients (NP); with omnivorous fish and nutrients (ONP); and, with zooplanktivorous fish and nutrients (ZNP). The two planktivory types reduced the zooplankton biomass and increased the phytoplankton biomass, but the omnivory of filter-feeding fish attenuated the trophic cascade magnitude. The fertilization by nutrients increases the nutrient concentrations in water and the phytoplankton biomass, but the effect on zooplankton is dependent of the trophic structure. In a general way, the effects of the fish and nutrient addition were addictive, but significant interactions among those factors were observed in the answer of some zooplankton groups. The effects of omnivorous fish over the temporal variability of phytoplankton and zooplankton biomass were very variable, the increase or reduce in variability of the plankton depending of the level of nutrients and of the analyzed variable. With base in this study, we conclude that the planktivory type exercised by the fish and the concentrations of nutrients in the water affects the force of pelagic trophic cascades and probably the success of biomanipulation programs for the handling of water quality in lakes and tropical reservoirs

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This study aims, to characterize the diversity of cephalopods by analyzing the stomach contents of fishes caught in the islands of St. Peter and St. Paul (ASPSP) and Fernando de Noronha (AFN). Also, verify the participation of cephalopods in the diet of their main predators. A total of 723 stomachs were collected, from 8 species of fish, caught by the fishery, 471 stomachs were from ASPSP and 252 were from the AFN. It was recorded the occurrence of food items (fish, cephalopods and crustaceans) and the cephalopods were identified to the lowest taxa possible, according to specialized literature. The Ommastrephidae family represented 84.46% of occurrence in the ASPSP and 63.48% in the AFN, confirming the importance of this family in the area studied and also in the diet of their predators. Among the species with greatest occurrence Ornitoteuthis antillarum was the most representative in both regions. This species had an average mantle length of 54.25 mm, thus demonstrating that the majority of this population is in the juvenile stage of development. The smallest species found was Argonauta nodosa with a mantle length of 4.06 mm and the largest was Ommastrephes bartrami, with 223.33 mm. In the AFN, the species richness (d) was 2.318, the diversity index (H ') was 1.454 and the measure of evenness (J) was 0.585. In the ASPSP, the species richness (d) was 2.66, the Shannon diversity index (H ') was 1.013 and the measure of evenness (J) was 0.373. AFN has a greater cephalopod diversity than ASPSP, confirming the pattern suggested by the Theory of Island Biogeography. Among the occurrence of prey items for all predators, the cephalopods are secondary preys. The most important cephalopod species in the diet of Thunnus albacares and Acantocybium solandri was Ornithoteuthis antillarum. These predators have different niche width the diet of Thunnus albacares is more specialized, but they have an overlap of 84.684% in the trophic niche, suggesting that in the ASPSP these two species may use similar niches

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O conhecimento científico sobre nutrição de animais de companhia tem aumentado de forma contínua, acompanhando o fenômeno visto em diversas áreas de conhecimento. Na última década, têm-se prioritariamente pesquisas direcionadas ao uso de nutrientes na promoção de saúde, prevenção de doenças degenerativas, melhoria da qualidade de vida e aumento da expectativa de vida de cães e gatos. Este direcionamento de pesquisas é, em grande parte, explicado pela importância que cães e gatos assumiram na vida das pessoas, fazendo com que as decisões alimentares dos proprietários com seus animais se assemelhassem às que adotam para si próprios. A publicação da nova revisão do Nutrient Requirements of Dogs and Cats em 2006 foi, talvez, o avanço recente mais significativo, trazendo novo entendimento sobre necessidades energéticas e de nutrientes nas diferentes fases de desenvolvimento e estados fisiológicos. Apesar destes avanços, ainda são necessárias pesquisas na área de caracterização físico-química e de utilização dos ingredientes, efeitos do processo de extrusão e mesmo de necessidades nutricionais, que conta com uma base pequena de artigos disponíveis, a maioria antiga. Talvez os desafios científicos mais importantes em nutrição de cães e gatos sejam metabolismo de carboidratos, importância da massa corporal magra na saúde, urolitíases, gerontologia, relação entre microbiota intestinal e saúde, imunonutrição e manejo nutricional em condições clínicas específicas importantes para estas espécies.

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Octopus insularis, target species in this study, is the dominant benthic octopus of the North and Northeast Brazil. Studies on behavior and ecology of the species have been conducted primarily on oceanic islands, with little information on the continental populations. In this study, two regions of the coast of RN, Rio do Fogo and Pirangi, were chosen for the characterization of the niche by O. insularis populations. The dietary niche, habitat and distribution of O. insularis of oceanic islands and the mainland, were compared. In addition, individual characteristics of feeding behavior in a population at Atol das Rocas was studied, taking into account the size of individuals, the proximity of the dens and characteristics of their "personality". The diet of the Rio do Fogo population was composed mainly of bivalve molluscs (82%), unlike Pirangi population that has a diet consisting mainly of crustaceans Decapoda (68%), similar to that described for the populations of the islands. Consequently, the feeding niches of the island populations were more similar, with greater overlap, but the niche breadth of the continent was larger. The habitats of occurrence on the coast includes reefs, rocks, gravel and an environment called Restinga, a plateau composed of biogenic gravel, sand, sponges and algae, showed a high density of animals. Similarly to that found in the islands, O. insularis in the continent, had a clumped distribution, and a bathymetric segregation between small and large individuals. The differences in diet composition among populations were explained by differences in habitat and coverage of the substrate, which may be directly influencing the diversity and prey availability in these environments. The individual analyzes of the population at Atol das Rocas, showed no relationship between the degree of individual specialization and the different personalities, or the distance between dens. The results suggest that the foraging strategy with greater availability of prey in the environment has an influence on diet octopuses over preferences or personalities

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Avaliaram-se os efeitos da utilização de ciclos alternados de restrição alimentar e realimentação no crescimento do pacu, durante o período de engorda, e a viabilidade desta prática na produção comercial da espécie. Juvenis foram distribuídos em três tanques e submetidos a diferentes manejos alimentares, constituindo os tratamentos: A (alimentado ad libitum), B (restrição alimentar de 4 semanas, realimentado por 9 semanas) e C (6 semanas de restrição alimentar, realimentado por 7 semanas), em um total de 13 semanas por ciclo (4 ciclos experimentais). No final de cada ciclo alimentar, 20 peixes de cada tratamento foram amostrados e os dados biométricos registrados. Os valores obtidos para peso, comprimento total e fator de condição (K) foram submetidos a ANOVA e as médias comparadas pelo teste de Duncan. Os resultados mostraram que o tratamento C é o mais indicado somente para outono/inverno, promovendo maior crescimento, menor custo com ração, baixa conversão alimentar e maior receita líquida parcial. Entretanto, durante as estações mais quentes do ano (primavera/verão) outros programas de alimentação devem ser testados, utilizando-se períodos mais curtos de restrição alimentar. Quando se tratou da produção anual, o tratamento A respondeu melhor em termos de biomassa produzida, apesar do maior gasto com alimentação, visto que, com o aumento da temperatura, o crescimento dos peixes dos demais tratamentos ficou prejudicado.

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This essay presents and discusses knowledge obtained through tradition taken as knowledge built along generations, transmitted from mouth to mouth and everyday experiences result of a non-scientific knowledge based on observation and hints given by more experient generations. The referred icon used to develop such a discussion in this essay is fishing. We point out the knoledge which enables the fishermen, among other dominions, to: find out the fish and other animals feeding habits; find their way through by astral influence during night navigation and learn the tide flowing based on the moon cycle. On what comes to fishing knowledge, the research was organized based on a bibliographic study about several ways of fishing in the Northern, Northeastern, Southern and Southestern regions of Brazil. In the Northern and Northeastern regions, the field research was also focused. Having interviews, photographs and films as reference, this part of the research was divided into two parts: the first one situated in the Amazonian Region in na area called Baixo-Tocantins, in the State of Pará where we worked with fishermen in the small towns of Abaetetuba and Igarapé-Miri; and the second one was held in the Northeastern region of Brazil, in the State of Rio Grande do Norte, where we worked with fishermen on the Piató Lake, in the small city of Assú. We tarted discussing based on a descriptive study of the fishing techniques used, aiming to identify them as an ordered activity, differed and classified by knoledge obtained through the years, based on the relationship between man and Nature. Creativity, stimulated by human curiosity, is also discussed and shown as a result of various fishing journeys. The myths, as a component of the fishing world, especially those which describe the relationship between men and waters, also have an outstanding place. At last, two fishing techniques belonging to the research field reference, are also described and analysed under the focus of construction and systematization of the knowledge related to fishing. The theory approach is based on reflection upon the tradition knowledge discussed by Almeida (2001), Balandier (1997), Câmara Cascudo (1957, 2000, 2002) and Claude Lévi-Strauss (1976, 1987 and 1991). The essay is an exercise of knowledge production which defends the "relink" of knowledge, as Edgar Morin suggests when dealing with the sciences of complexity

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This paper gives clues for the educative action in nutrition subjects. It deals about the professors experiences deployments lived in 2003 e 2004, both in Nutrition undergraduate course of the Federal University of the Rio Grande do Norte (UFRN), in Nutrition Education and Supervised Internship in Social Nutrition academic disciplines, as well as in the II Update Course in Nutrition Practices for Health Basic Care , offered to the supervisors nutritionists of internship, in this same department, being able to be characterized as an action-research, with interventionism purpose. The study stands out the importance of a new point of view about the nutritionist formation to overcome the limits imposed by the scientism, and the adoption of a complex and reflexive reference about the educational practice in this area. The corpus is made up by 81 undergraduate students alimentary autobiography (source of generating subjects for interventions with the nutritionists), 17 questionnaires and 05 interviews, being 03 of them biography (the start up for an initial dialogue with the nutritionists). The data found and the professors experiences allied to a theoretic reference, by the light of the education proposals for the XXI century were used as establishment elements for the proposition of five guidance axles used to build a complex and reflexive nutrition education, which are: 1) Take the cookery and the culture of eating together as significant elements for the human being integral formation; 2) Conceive the religion manifestations associated to feeding process as relevant elements of the human food culture; 3) Discuss the rupture nature/culture aiming the preservation of live in earth; 4) Search for the overcoming of the identity conflicts by a higher inclosing conscience degrees of being part of this process. 5) Face the limits of fragmented formation. The presented thesis stands that the autobiography method, allied to the freirean pedagogy and to a complex reference, could be taken as an important tool to the health educative subjects, contributing to the formation of reflective individuals able to transform themselves and the world.

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L accès et la permanence des étudiants à l université sont très présents dans les débats actuels relatifs à l'enseignement supérieur. De nombreuses mesures sont prises dans les politiques d'accès dans le but de réduire les inégalités et d'encourager les étudiants ayant moins de chances d'entrer dans l'enseignement supérieur, comme les étudiants issus de l'enseignement public, qui ont encore un niveau inférieur à celui souhaité. Lorsque ces élèves réussissent à terminer leurs études secondaires, passer l'examen d'entrée et réussir leur entrée dans l'enseignement supérieur ils se considèrent comme « victorieux ». Cette étude (pour le Master de l UFRN), développée au sein du groupe de recherche de la formation et professionnalisation des enseignants (PPGed / UFRN), vise à étudier la trajectoire des élèves issus des écoles publiques qui accèdent à une université publique. Nous avons interviewé 12 étudiants, six de l'Université fédérale de Rio Grande do Norte (UFRN) et 6 de l'Université d'État de Bahia (UNEB) inscrits à différents cours du premier cycle (Licence). Nous cherchons savoir comment s est déroulé leurs parcours au sein de l'Université, notamment en ce qui concerne la préparation aux examens d'entrée à l université (Vestibular) , la motivation du choix de cours, la première année à l'université, les habitudes d'étude, la relation avec l'apprentissage et les perspectives quant à l'avenir des élèves interrogés. Nous nous sommes référés aux travaux menés par Zago (2006), Ramalho (2003), Charlot (1997), Galland et Gruel (2009), Coulon (2008), Tinto (1993), Doray et l'équipe canadienne du CIRST (2009). L'entrée à l'université comporte un triple processus, institutionnel (formelles et informelles), intellectuel (composantes cognitives et académiques) et social (vie sociale au sein de l'université). L'étudiant entre à l'université et y trouve une nouvelle culture, de nouvelles connaissances et devra apprendre à être universitaire. Apprendre à surmonter le moment de l étrangeté et bien passer par le processus de l'apprentissage des règles, des codes de son nouveau statut et s accommoder de sa position d étudiant à l'université, arrive enfin, le temps d'affiliation, c'est à dire, le moment de l'admission où l'étudiant se sent comme un «vétéran», et qu il peut dire que les dangers de l'abandon sont passés et qu il pourra continuer son parcours avec succès. Cette étude vise à apporter des connaissances nouvelles sur les étudiants issus des écoles publiques, comme contribution au domaine des politiques d'accès et de permanence à l université et de soutien pédagogique au sein de cette institution

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Dois experimentos foram realizados para investigar a relação cálcio (Ca):fósforo disponível (Pd) e o nível de fitase (UF) no primeiro e segundo ciclos de postura. No primeiro ciclo de postura, 128 aves foram distribuídas em arranjo fatorial 3 × 2 + 1, composto de três relações Ca:Pd (14:1 = 4,2% Ca e 0,30% Pd; 12:1 = 3,5% Ca e 0,30% Pd; e 9:1 = 3,5% Ca e 0,38% Pd), dois níveis de fitase (0 e 600 UF) e uma relação Ca:Pd controle (11:1 - 4,2% Ca e 0,38% Pd). No segundo ciclo de postura, 240 aves foram distribuídas em arranjo fatorial 2 × 2 × 2, composto de dois níveis de cálcio (3,5 e 4,2%), dois de fósforo disponível (0,30 e 0,38%) e dois de fitase (0 e 600 UF). No primeiro ciclo, entre as aves alimentadas com as rações sem fitase, o maior peso dos ovos (PO) foi obtido com a relação 9:1 (3,5% Ca e 0,38% Pd) e o menor, com a relação 12:1 (3,5% Ca e 0,30% Pd). A melhor massa de ovos (MO) e conversão alimentar por massa de ovos (CAMO) foram observadas nas aves alimentadas com a ração com relação Ca:Pd 14:1 e a pior, com a ração formulada com relação 12:1. Nas aves alimentadas com a ração com fitase, a melhor conversão alimentar por massa de ovos foi obtida com a relação 12:1 (3,5% Ca e 0,30% Pd) e a pior, com a relação 9:1 (3,5% Ca e 0,38% Pd). No segundo ciclo, o consumo de ração (CR) reduziu com o aumento dos níveis de cálcio (3,5 para 4,2%), fósforo disponível (0,30 para 0,38%) e fitase (0 para 600). As conversões alimentares por massa de ovos e por dúzia de ovos melhoraram, respectivamente, com o aumento dos níveis de fósforo disponível e de fitase, enquanto a gravidade específica melhorou com o aumento do nível de cálcio da ração. Para poedeiras no primeiro ciclo de postura, recomendam-se as relações 14:1 (4,2% Ca:0,30% Pd) sem fitase e 12:1 (3,5% Ca:0,30% Pd) com 600 UF e, para aves no segundo ciclo de postura, recomenda-se relação correspondente a 4,2% Ca e 0,38% Pd. A suplementação de rações deficientes em fósforo disponível com 600 UF melhora o peso dos ovos no segundo ciclo de postura.

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The traditional fishing with rafts is characterized by unpredictability, high stakes and inadequate work conditions. The extensive working hours, physical wear, inadequate nutrition, unsanitary conditions, lack of salvage equipment and instruments suitable working, added by the presence of changes in the nutritional status of fisherman, that contribute to the picture of insecurity in high seas, injuries and health. This study aimed to analyze the activity of the fisherman s from Ponta Negra, Natal / RN, and check the conditions of supply of these fishermen and their implications on health and development of their work. To this finality, was used a methodology based on the ergonomic work analysis employing techniques such as observational and interactional conversational action, listening to the answers, observation protocols, photographic and video records. The script conversational dynamic action was developed from literature searches about the artisanal fisheries, culture and food habits of this population, and analyzes the overall situation of focus and two reference situations. To collect data on the usual diet of fisherman as well as quantitative and qualitative analysis that was used for data analysis and 24h recall the Food Frequency Questionnaire (FFQ). The impact of this power to the health of fisherman was evaluated performing a nutritional assessment. The results revealed that the fishermen carry out their activities with poor working conditions, health and nutrition. Feeding practices of these fishermen undertake development work, making it even more stressful, as well contributing to the emergence of Chronic Noncommunicable Diseases. The management of the activity, as well as the current structure of the vessel, also contributes to the adoption of inappropriate feeding practices during the shipment of catch. The results of this indicate the need for adequate interventions in order to assist in recovery and / or maintenance of health of fisherman minimizing reflections of nutritional disorders for the development activity by improving the quality of life in this population

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Objetivou-se estudar o efeito de diferentes planos alimentares, de acordo com os níveis de triptofano, sobre o desempenho e estresse (pela avaliação de parâmetros fisiológicos) de codornas japonesas (Coturnix coturnix japonica) nas fases de recria e postura. Cento e noventa e duas codornas japonesas na fase de recria (30 a 44 dias de idade) foram alojadas em gaiolas e distribuídas em um delineamento em blocos casualizados, com quatro planos de nutrição [0,27 (controle); 0,52; 0,77 ou 1,02% de triptofano], seis repetições e oito aves por parcela. Foram avaliados os parâmetros de desempenho (consumo de ração, ganho de médio peso, conversão alimentar e taxa de mortalidade) e os parâmetros fisiológicos das aves (relação heterófilo/linfócito e concentração de corticosterona no plasma sangüíneo). Outras 192 codornas japonesas na fase de postura (45 a 146 dias) foram distribuídas em delineamento de blocos ao acaso e submetidas a quatro planos de nutrição (0,23 [controle]; 0,48; 0,73 ou 0,98% de triptofano), com seis repetições e oito aves por parcela. Foram avaliados o consumo de ração, a produção de ovos, a conversão alimentar por dúzia de ovos, a taxa de mortalidade, a relação heterófilo/linfócito e a concentração de corticosterona no plasma. Os níveis de triptofano testados não afetaram o desempenho e os parâmetros fisiológicos de codornas japonesas nas fases de recria e postura.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)