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Les travaux présentés dans ce mémoire ont été motivés par l'importance économique de l'élevage de la crevette bleue du pacifique Litopenaeus stylirostris dont les fortes mortalités sont principalement dues au développement de maladies bactériennes et virales. Ils ont consisté en la caractérisation des deux premiers membres d'une famille originale de peptides multifonctionnels présents chez les crevettes pénéides, les stylicines. Ces peptides, nommés stylicines 1 et 2, sont des peptides anioniques (pI < 6.0), formés d'une région amino-terminale riche en résidus de type proline et d'une région carboxy-terminale riche de treize résidus cystéines. Ces molécules sont synthétisées et stockées dans de petits granules présents dans le cytoplasme des hémocytes. Pour mieux appréhender leurs rôles dans la réponse immunitaire des crevettes à une infection par des Vibrio, leurs formes recombinantes ont été produites dans E. coli BL21 (DE3) plysS, purifiées et caractérisées. Les deux rstylicines présentent des activités antiproliférative et anticoagulante. Seule la rstylicine1 présente des activités antimicrobiennes : antifongique sur Fusarium oxysporum (CMI<2.5 µM), et antibactérienne (bactériostatique) sur Vibrio sp (CMI<80 µM). Ce peptide est également capable de se lier aux LPS des bactéries à Gram (-) (Kd= 9.6x10-8 M) et d'agglutiner V. penaeicida "in vitro". Enfin, l'existence de gènes codant des formes modifiées de la stylicine1, chez certaines crevettes, pourrait être en relation avec une diminution de la résistante des individus aux infections. / The work reported here was motivated by the economical importance of the pacific blue shrimp Litopenaeus stylirostris farming where high mortality rates are due to bacterial and viral diseases. It consists in the characterisation of two original peptides, the first members of a new multifunctional family of peptides from peneide shrimps, the stylicines. Those two peptides, named stylicines 1 and 2, are negatively charged (pI < 6.0), and characterised by a proline-rich N-terminal region and a C-terminal region containing 13 cysteine residues. Stylicines are synthesized by heamocytes where they are stored within small cytoplasmic granules. To understand the role of these peptides in the immune response of shrimps to a vibrio infection, their recombinant forms were produced in E. coli BL21 (DE3) plysS, purified and characterised. The two rstylicines display biological anti-proliferative and blood clotting activities. Only rstylicine 1 displays antimicrobial activities: antifungal against Fusarium oxysporum (MIC<2.5µM) and bacteriostatic against Gram (−) bacteria, Vibrio sp. (MIC<80µM). Moreover this peptide displays an LPS-binding activity (dissociation constant (Kd) of 9.6×10−8 M) and agglutinate Vibrio. penaeicida "in vitro". Finally, the presence of sequences coding for modified forms of stylicine 1 in some shrimp's genome may be in relation with their lower ability to survive infections.

Aquaculture and fisheries hold promise for supplying a growing world population with healthy food produced without undermining the earth’s carrying capacity. However, just as livestock production and agriculture, seafood production can have negative environmental impacts and if a continuous or even increased supply is to be guaranteed, the pressure on affected ecosystems needs to be limited. Due in part to a perceived failure of other governance mechanisms in improving the environmental performance of the sector, a large number of voluntary market based standards for farmed and wild caught seafood have been developed. Nonetheless, the knowledge base on the extent to which implementation leads to environmental improvements remains limited. Moreover, the role of consumers in driving demand for eco-labeled seafood is presently an under-researched area. This thesis aims at reducing this knowledge gap through an examination of the potential environmental effectiveness of aquaculture eco-certification and internal, psychological variables predicted to be of importance for sustainable seafood consumption. Put differently, what is the potential of eco-certification in greening the blue revolution and fuel ‘turquoise growth’, and how can consumer demand be spurred? In Paper I, the role of eco-certification in improving the growing aquaculture sector at large was explored. Results showed that environmental effects at global scale likely will be limited due to e.g. partial coverage of species groups and environmental impacts, and a lack of focus on Asian markets and consumers. In Paper II the environmental performance of eco-certified and non-certified mangrove-integrated shrimp farms in Vietnam was compared by using Life Cycle Assessment and put in relation to conventional, more intensive farms. While there was no substantial difference between certified and non-certified farms in terms of environmental impacts, emissions of greenhouse gasses were higher for mangrove-integrated than conventional farms due to mangrove land use change. The results from Paper III demonstrated that the body of literature investigating ecological effects of seafood eco-certification is limited. ‘Spatially explicit ecosystem service information’ (ES-information) on e.g. key ecosystem services and biodiversity in a given area is suggested to have potential to improve sustainability standards. Taking guidance from the pro-environmental behavior literature, consumers in Stockholm, Sweden were consulted on awareness of and attitudes towards eco-labeled seafood (Paper IV-V). Two variables, concern for environmental impacts and knowledge about seafood eco-labels were the best predictors for stated eco-labeled seafood purchasing. Moreover, there seemed to be a misalignment between consumers’ expectations on eco-labeled food in general and certification requirements for eco-labeled seafood. From this set of findings, a number of improvements of current seafood eco-certification are suggested. First, include an LCA-perspective in standards to a higher degree than presently done and provide readily available ES-information in the implementation and evaluation phase of certification. Second, introduce standardized mechanisms for capturing potential environmental improvements over time. And finally, stimulate demand by targeting Asian consumers and markets as well as strengthen consumer eco-label awareness and emotional involvement. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Manuscript.</p><p> </p>

This study examines the marketing strategies employed by vendors at the Westwego shrimp lot in Westwego, Louisiana. Given the fluctuating market conditions and rising costs of seafood production, seafood vendors in the Gulf Coast region must look continuously for new ways to market their product as a cultural commodity. This thesis argues that shrimp becomes a cultural commodity at the Westwego shrimp lot, and that through marketing strategies, vendors at the Westwego shrimp lot both resist and accept certain aspects of globalization. The presence of imports, a presence that emerges in the context of globalization, poses a large threat to the industry‟s survival. Vendors both consciously and unconsciously market shrimp as food and symbol. An analysis of their efforts may contribute to understanding the process of cultural commodification.

O objetivo deste trabalho foi identificar na cadeia produtiva do camarão Litopenaeus vannamei os perigos à saúde animal e à saúde pública e as respectivas medidas de controle, a partir de levantamentos bibliográficos. Os principais perigos à saúde animal identificados foram os vírus da Mancha Branca, Cauda Amarela, Mionecrose Infecciosa, síndrome da Taura e bactérias hepatonecrosantes dos camarões, que ocasionam grandes prejuízos para a cadeia produtiva, devido à queda da produtividade e às elevadas taxas de mortalidade. Esses perigos apresentam riscos à saúde animal, quando se mantêm viáveis nas plantas de cultivo, decorrente das práticas inadequadas de manejo sanitário e da queda de qualidade da água nos viveiros. Quanto aos riscos à saúde humana, alguns patógenos como: Vibrio spp, Salmonella spp e Staphylococcus aureus apresentam perigo se presente e viável no camarão contaminado. O uso abusivo e indiscriminado de metabissulfito de sódio em diferentes concentrações nas plantas de processamento, de contaminantes inorgânicos e resíduos de medicamentos veterinários nas criações podem resultar em níveis elevados de toxicidade aos animais e ao ambiente, precisando, consequentemente ser corrigido com a adoção de boas práticas de manejo do ambiente, implantação de vazio sanitário e estabelecimento de parâmetros microbiológicos e ambientais nos viveiros. Por ser uma atividade promissora para o desenvolvimento socioeconômico do país, é de extrema importância a adoção de medidas de controle destes perigos, que incluem a aplicação dos princípios das &quot;Boas Práticas&quot; e da &quot;Análise de Perigos e Pontos Críticos de Controle&quot; no manejo ambiental e sanitário em todos os elos da cadeia produtiva, dos criatórios até o consumo. / The objetive of this study was to identify in the production chain of shrimp Litopenaeus vannamei the hazards to animal health and public health and their control measures, from the literature. The main hazards to animal health were identified: viruses White Spot, Yellow Tail, Infectious Myonecrosis, Taura syndrome and Hepatonecrotysing bacteria of prawns, which promote large losses in the supply chain due to a drop in productivity and high mortality rates. They are considered dangerous to animal and human health, because they maintain viable pathogens in crop plants, resulting from inadequate health management practices and falling water quality in the ponds. In relation to chemical hazards, the indiscriminate use of sodium metabisulphite, inorganic contaminants and residues of veterinary drugs and pesticides can result in situations of high toxicity to animals and the environment, and must be controlled by adopting good environmental management practices, implementation of depopulation and the establishment of microbiological parameters and environmental conditions in nurseries. Physical hazards can be related to any failure in the process of industrialization and commercialization, in which the detection of foreign objects should be checked by visual inspection and the use of metal detectors. Since it is a promising socio-economic development of the country, it is extremely important to adopt measures to control these hazards, including the principles of &quot; Good Practice&quot; and &quot;Hazard Analysis and Critical Control Points &quot; in the management of environment and health in all links in the production chain, from the farms to the consumers.

Os camarões do gênero Palaemon Weber, 1795 possuem ampla variedade morfológica, ecológica e reprodutiva. Estudos baseados em dados moleculares indicam que o gênero pode não ser monofilético. Por outro lado, análises cladísticas baseadas em dados morfológicos recuperam Palaemon como um grupo natural. Além de questões em nível genérico, a validade de algumas espécies com ocorrência no Brasil também é questionada. Nesse contexto, foi utilizada uma abordagem molecular (genes COI, 16S, H3 e 18S) e morfológica com ampla amostragem taxonômica para 1) avaliar a hipótese de monofilia do gênero Palaemon; 2) avalia a hipótese de que padrões biogeográficos, de ocupação de hábitat, reprodutivos e morfológicos acompanham as relações filogenéticas entre as espécies de Palaemon; 3) avaliar o status taxonômico das espécies com ocorrência no Brasil. A filogenia recuperada indica que as espécies de Palaemon estão distribuídas em três linhagens distintas e caracteres morfológicos permitem a identificação de pelo menos quatro grupos monofiléticos. Os resultados indicam a necessidade de criação de dois novos gêneros e revalidação de Alaocaris Holthuis, 1949. A provável colonização da América e Europa ocorreu em mais de um momento em cada região e o ancestral comum mais recente da maioria das espécies de Palaemon, Macrobrachium Spence Bate, 1868 e gêneros próximos provavelmente foi uma linhagem anfídroma. A análise conjunta de dados moleculares e morfológicos demonstram a existência de nove espécies de Palaemon no Brasil, oito previamente descritas (P. argentinus, P. carteri, P. ivonicus, P. mercedae, P. northropi, P. octaviae, P. paivai, P. pandaliformis) e uma espécie nova (P. yuna). / Shrimps of the genus Palaemon Weber, 1795 have wide morphological, ecological and reproductive variability. Studies based on molecular data indicate that the genus might not be monophyletic. On the other hand, cladistics analyses based on morphological data recover Palaemon as a natural group. Besides generic level issues, the validity of some species from Brazil is questioned. In that context, we used a molecular (COI, 16S, H3 and 18S genes) and morphological approach with broad taxonomic sampling in order to 1) evaluate the hypothesis of monophyly of the genus Palaemon; 2) evaluate the hypothesis that biogeographical, habitat occupation, reproductive and morphological patterns follow the phylogenetic relationships among the species of Palaemon; 3) evaluate the taxonomic status of the species of Palaemon from Brazil. The recovered phylogeny indicates that the species of Palaemon are distributed into three distinct lineages. Morphological characters allow the identification of at least four monophyletic groups. The results indicate that the erection of two new genera and re-erection of Alaocaris Holthuis, 1949 is needed. The colonization of America and Europe probably took place more than once in each continent. The more recent common ancestor of the majority of the species of Palaemon, Macrobrachium Spence Bate, 1868 and closely related genera probably was an amphidromous lineage. The molecular and morphological approach indicates that there are nine species of Palaemon in Brazil, eight of them previously described (P. argentinus, P. carteri, P. ivonicus, P. mercedae, P. northropi, P. octaviae, P. paivai, P. pandaliformis) and one new species (P. yuna).

O depósito do Morro dos Seis Lagos (DMSL) é o maior depósito de Nb até hoje encontrado. A mineralização é laterítica, ocorrendo associada ao corpo principal do Complexo Carbonatítico Seis Lagos (CCSL). Este trabalho apresenta resultados da datação U-Pb (por MC-ICP-MS com LASER acoplado) de zircões de sete amostras abrangendo todos os tipos litológicos conhecidos no CCSL/DMSL: rocha encaixante (gnaisse), veio de feldspato na encaixante, siderita carbonatito (3 amostras) e crostas ferruginosas mineralizadas em Nb (2 amostras). Os zircões do gnaisse e do veio de feldspato forneceram idades de, respectivamente, 1.826 ± 9 Ma e 1.839 ± 29 Ma, as quais mostram que a litofácies Tarsira do Complexo Cauaburi (o embasamento do Domínio Imeri na Província Rio Negro) é de 16 Ma a 29 Ma mais antiga do que o anteriormente suposto. Os zircões de duas amostras de carbonatito forneceram idades de 1.837 ± 8 Ma e 1.841 ± 7 Ma, as mais antigas encontradas no Domínio Imeri no Brasil, interpretadas como relacionadas a rochas profundas, cujos zircões foram capturados pelo magma carbonatitico durante sua ascensão A idade de 1.818 ± 8 Ma obtida em zircões da crosta pisolítica indica que o Complexo Cauaburi foi uma importante fonte para os clastos presentes nesta crosta. A idade de 1.873 ± 70 em zircões da crosta fragmentada pode indicar que rochas mais antigas, de outra provincia, também participaram como fonte de clastos para a cobertura laterítica do CCSL. Os zircões de uma amostra de carbonatito da parte central do corpo forneceram duas idades: 1.841 ± 7 Ma e 1.457 ± 71 Ma. Esta última idade é interpretada como a idade máxima do CCSL. Análises por microssonda eletrônica indicam que os zircões mesoproterozoicos têm alguma afinidade com carbonatito. A possibilidade do CCSL ter uma idade mesoproterozoica é discutida à luz do atual conhecimento da evolução geológica da Província Rio Negro, concluindo-se por uma relação com a evolução do Cinturão K’Mudku. / The Morro dos Seis Lagos deposit (MSLD) is the world’s largest Nb-deposit. The lateritic mineralization occurs associated to the major body of the Seis Lagos Carbonatite Complex (SLCC). This paper presents results of U-Pb dating (by MC-ICP-MS, coupled to LASER) of zircons from seven samples that cover all of the known lithotypes in the SLCC/MSLD: host rock (gneiss), feldspar/kaolin intercalation in the host rock, siderite carbonatite (3 samples), and ferriferous Nb-mineralized crust (2 samples). Zircons from the gneiss and the feldspathic vein provided ages of 1.826 ± 9 Ma and 1.839 ± 29 Ma, respectively, which implies that the lithofacies Tarsira of the Cauaburi Complex (the basement of the Imeri Domain in the Rio Negro Province) is 16 Ma to 29 Ma older than previously supposed. Zircons from two carbonatite samples provided ages of 1.837 ± 8 Ma and 1.841 ± 7 Ma which are interpreted as ages of deeper host rocks whose zircons were extracted by the rising carbonatitic magma The age of 1.818 ± 8 Ma obtained in zircons from the pisolitic crust indicate the Cauaburi Complex as the main source of clasts for this crust. The age of 1.873 ± 70 in zircons from the fragmented crust may indicate that rocks from another province older than the Rio Negro Province also contributed as source of clasts to the SLCC lateritic cover. The zircons of a carbonatite sample from the central part of the carbonatite body yield two ages: 1.841 ± 7 Ma and 1.457 ± 71 Ma. The late age is interpreted as the maximum age of the SLCC. Analysis by electron microprobe reveals some evidences that the mid-Proterozoic zircons could be carbonatite zircons. The possible age of 1.457 Ma for the SLCC is discussed in view of the present knowledge on the geology of the Rio Negro Province; a relation with the evolution of the K'Mudku Belt is prognosticated.

El presente trabajo de investigación busca identificar y analizar los principales problemas relacionados a la exportación de cola de langostino de acuicultura con destino a EEUU durante los años 2013-2018; se trabajó una investigación cualitativa longitudinal, utilizando herramientas como el análisis de documentos y entrevistas a profundidad semi estructuradas. La estructura establecida para el presente trabajo fue en primer lugar, el análisis del marco teórico, donde se buscó estudios pasados que sustenten y acrediten nuestro problema de investigación; en segundo lugar, se realizó un análisis documental; para ello se emplearon fuentes como SUNAT, VERITRADE y TRADEMAP, que proporcionan información real de toda la actividad económica del país ya sea importación o exportación del producto a investigar; y por último, en tercer lugar, fue la realización de entrevistas a profundidad; las mismas que fueron realizadas a profesionales del rubro que tienen en promedio 10 años de experiencia y laboran en las principales empresas del sector. Se tomó una muestra de un total de 14 entrevistas semiestructuradas, dado a que se llegó al punto de saturación. Finalmente, se realizó un análisis en triangulación, ya que se contrastó lo expresado en el marco teórico, con lo hallado en los documentos, y el resultado de las entrevistas; obteniendo nuevas categorías, que servirán como base para otros investigadores que desarrollen un tema relacionado. / This research seeks to identify and analyze the main problems related to the export of shrimp tail of aquaculture to the US during the years 2013-2018; a longitudinal qualitative research was carried out, using tools such as document analysis and semi-structured in-depth interviews. The structure established for the present work was, first of all, the analysis of the theoretical framework, where past studies were sought to sustain and accredit our research problem; Secondly, a documentary analysis was carried out; For this, sources such as SUNAT, VERITRADE and TRADEMAP were used, which provide real information on all the economic activity of the country, whether it is import or export of the product to be investigated; and finally, it was conducting in-depth interviews; the same ones that were carried out to professionals of the sector that have on average 10 years of experience and work in the main companies of the sector. A sample of a total of 14 semi-structured interviews was taken, given that the point of saturation was reached. Finally, an analysis was carried out in triangulation, since what was expressed in the theoretical framework was contrasted with what was found in the documents and the results of the interviews; obtaining new categories, which will serve as a basis for other researchers to develop a related topic. / Tesis

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