With the considerable expansion of the brazilian fishing industry and a greater population demand for food of protein origin, fish production increased and with it also emerged an accelerated generation of waste from the processing of these, which are usually discarded in the environment without any type of treatment. These residues are composed of organic material such as head and shells, rich in bioactive compounds such as carotenoids and their use can increase the economy of the industrial sector, as well as communities that depend economically on fishing and processing, and contribute to mitigate the effects of the degradation of the environment, becoming an alternative so that the fishing activity becomes more sustainable from the technical, environmental, economic and social point of view. In the municipality of Pirambu, the economy is based on fishing, mainly the craft and many families have this activity as a source of subsistence. However, the degradation and silting of the Japaratuba River that cuts through the city has attracted attention from the political authorities and the local population, since it affects the fishing sector of this region, thus arousing the interest of investigation of its causes. It is suspected that one of the possible reasons for the observed environmental degradation may be related to the disposal of organic material from the processing of fish and shrimp in the port that are discarded in the riverbed. In view of the foregoing, the thesis presented had the objective of proposing a way to add value to the shrimp residues processed in the region by extracting the astaxanthin carotenoid using a simple technique with a lower environmental impact. An alternative to the use of sunflower oil and castor oil as solvents in the extraction process was suggested in order to collaborate with the fish industry and the small shrimp beneficiaries of the fishing community of the region of Pirambu-SE, when reviewing their production processes by means of the proposal to take advantage of their waste and reduce the costs generated by their disposal. In addition to optimizing the extraction of astaxanthin in the study of the independent temperature and extraction time variables, in order to increase its concentration and reduce costs, as well as offer the food, pharmaceutical, cosmetic and animal feed industries a new source of natural carotenoids. The results obtained indicate the ideal extraction conditions to obtain a higher carotenoid concentration (18.43mg.g-1) with the use of sunflower oil at an average temperature of 70°C in approximately 5 hours. In the case of castor oil, it was necessary to obtain the values of the parameters wavelength (máx= 435,8nm) and specific extinction coefficient (E = 3056), allowing the calculation of yield of the astaxanthin, considering the ideal conditions indicated to obtain a higher concentration of the carotenoid (14.22 mg.g-1) the time of 10 hours and temperature 80°C. The research made possible the insertion of a technique to obtain a high value-added carotenoid in a simple way with low environmental impact, becoming an income opportunity for shellfish that depend on the shrimp processing, besides mitigating the disposal of a material with high organic load that can cause several environmental, economic and social damages. / Com a considerável expansão da indústria pesqueira brasileira e uma maior demanda populacional por alimentos de origem protéica, a produção de pescados aumentou e com ela surgiu também uma acelerada geração de resíduos provenientes do processamento destes, os quais são usualmente descartados no ambiente sem nenhum tipo de tratamento. Estes resíduos são constituídos de material orgânico como cabeça e carapaças, ricos em compostos bioativos como os carotenóides e o aproveitamento destes pode incrementar a economia do setor industrial, bem como de comunidades que dependem economicamente da pesca e beneficiamento, além de contribuir para mitigar os efeitos da degradação do meio ambiente, convertendo-se numa alternativa para que a atividade pesqueira se torne mais sustentável do ponto de vista técnico, ambiental, econômico e social. No município de Pirambu, a economia é baseada na pesca, principalmente a artesanal e muitas famílias tem esta atividade como fonte de subsistência. Porém, a degradação e assoreamento do Rio Japaratuba que corta a cidade tem chamado atenção das autoridades políticas e da população local, pois afeta o setor pesqueiro desta região despertando, portanto, o interesse de investigação das suas causas. Suspeita-se que uma das possíveis razões do desgaste ambiental observado pode estar ligada ao descarte de material orgânico proveniente do beneficiamento de peixes e camarões no porto que são descartados no leito do rio. Diante do exposto, a tese apresentada teve como objetivo propor uma forma de agregar valor aos resíduos do camarão processado na região por meio da extração do carotenóide astaxantina utilizando uma técnica simples e de menor impacto ambiental. Para isso sugeriu-se uma alternativa ao uso de óleo de girassol e óleo de mamona como solventes no processo de extração afim de colaborar com a agroindústria de pescados e com os pequenos beneficiadores de camarão da comunidade pesqueira da região de Pirambu-SE, ao rever seus processos produtivos por meio da proposta de aproveitar seus resíduos e diminuir os custos gerados com seu descarte. Além de otimizar a extração de astaxantina no estudo das variáveis independentes temperatura e tempo de extração, com o intuito de aumentar sua concentração e reduzir custos, bem como oferecer as indústrias de alimentos, farmacêutica, cosmética e de ração animal uma nova fonte de carotenóides naturais. Os resultados obtidos apontam as condições ideais de extração para obter uma maior concentração do carotenóide (18,43mg.g-1) com o uso de óleo de girassol numa temperatura média de 70°C em aproximadamente 5 horas. No caso do óleo de mamona, pelo ineditismo no uso deste solvente para este fim foi necessário obter os valores dos parâmetros comprimento de onda (máx=435,8nm) e coeficiente de extinção específico (E=3056) possibilitando o cálculo do rendimento da astaxantina, sendo cosiderada as condições ideais apontadas para obter uma maior concentração do carotenóide (14,22mg.g-1) o tempo de 10 horas e temperatura 80°C. A pesquisa possibilitou, portanto, a inserção de uma técnica de obtenção de um carotenóide de alto valor agregado de forma simples e com baixo impacto ambiental, tornando-se uma oportunidade de renda para marisqueiras que dependem do beneficiamento do camarão, além de mitigar o descarte de um material com elevada carga orgânica que pode acarretar diversos prejuízos de ordem ambiental, econômica e social. / São Cristóvão, SE

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-07-24T16:03:54Z No. of bitstreams: 1 2009 - Helaine dos Reis Flor.pdf: 3447034 bytes, checksum: 3861cf7664eb46a21add49a26a4479c2 (MD5) / Made available in DSpace on 2017-07-24T16:03:54Z (GMT). No. of bitstreams: 1 2009 - Helaine dos Reis Flor.pdf: 3447034 bytes, checksum: 3861cf7664eb46a21add49a26a4479c2 (MD5) Previous issue date: 2009-09-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / Farfantepenaeus brasiliensis is a native species also known as the pink shrimp, and is one of the most explored fishing resources of the Brazilian coastline. This study aims to evaluate the reproductive performance of the F. brasiliensis raised in captivity submitted to different diets and sex ratios. Wild broodstock were captured in the Ba?a de Sepetiba, near to the Restinga da Marambaia and were kept for 107 days in maturation tanks at the Esta??o de Biologia Marinha da Universidade Federal Rural do Rio de Janeiro (EBM-UFRRJ). After ten days of acclimatization, the animals were randomly assigned to 18 polyethylene tanks, 450L volume, with constant aeration, continuous filtered seawater exchange, feeding trays and pieces of PVC pipes to serve as shelter. Each tank stored six animals. The experimental design was completely randomized with six treatments and three repetitions for each. Three diet feeding protocols were evaluated: A- 25% commercial diet /75% fresh food; B- 50% commercial diet 50% fresh food e C- 75% commercial diet /25% fresh food and two sex rations (male:female) 1:1 and 1:2 were evaluated. Females shrimp were unilaterally eyestalk ablated and marked with alternate cuts on the uropods for individual identification. The number of spawns, fecundity and hatching rate were used as the criteria for evaluation of reproductive performance. The 1M:2F sex ratio and the B feeding protocol had the best results regarding reproductive performance related to number of eggs/female and total egg production. Treatments that used the C diet presented the best hatching rates, despite of the low number of spawns. Throughout the experiment moulting occurred, however the spawning stopped between the 81st and the 90th day, probably due to physiological stress. At the end of the experiment, the females presented low survival rate in every treatment, possibly due to handling stress occurred during the gonadal maturation checks. Overall results of the present study indicated that it is possible to reproduce the F. brasiliensis in captivity, in small tanks, showing satisfactory reproductive performance. Nevertheless, it is necessary to re-evaluate the animal handling, in order to decrease the mortality and optimize the performance in captivity. / Farfantepenaeus brasiliensis ? uma esp?cie nativa conhecida como camar?o-rosa, e um dos recursos pesqueiros mais freq?entes e explorados na costa brasileira. Este trabalho teve como objetivo avaliar o desempenho reprodutivo de F. brasiliensis em cativeiro submetidos a diferentes dietas e propor??es sexuais. Os reprodutores selvagens foram capturados na Ba?a de Sepetiba, pr?ximo ? Restinga da Marambaia e mantidos durante 107 dias em tanques de matura??o na Esta??o de Biologia Marinha da Universidade Federal Rural do Rio de Janeiro (EBM-UFRRJ). Ap?s dez dias de aclimata??o, os animais foram distribu?dos aleatoriamente em 18 tanques de polietileno com volume ?til de 450L, com aera??o constante, fluxo cont?nuo de ?gua do mar filtrado, bandejas de alimenta??o e peda?os de canos de PVC para servir de abrigo para os animais. Em cada tanque foram colocados 6 animais. O delineamento experimental foi inteiramente casualizado com seis tratamentos e tr?s repeti??es cada. Foram avaliadas tr?s dietas alimentares: A-25% ra??o/75% alimento fresco; B-50% ra??o/50% alimento fresco e C-75% ra??o/25% alimento fresco e duas propor??es sexuais (macho:f?mea) de 1:1 e 1:2.Todas as f?meas foram abladas e marcadas com cortes alternados nos ur?podos para identifica??o individual. A avalia??o do desempenho reprodutivo foi realizada atrav?s do n?mero de desovas, fecundidade e taxa de eclos?o de cada tratamento. A propor??o sexual 1M:2F e a dieta B apresentaram os melhores resultados de desempenho reprodutivo em rela??o ao no de desovas e fecundidade. Os tratamentos que receberam a dieta C foram os que apresentaram melhor taxa de eclos?o, apesar do baixo n?mero de desovas. Ocorreram mudas durante todo per?odo experimental, por?m a ocorr?ncia das desovas cessou entre 81o e 90o dia de experimento, provavelmente por desgaste fisiol?gico. Ao final do experimento, as f?meas apresentaram alta mortalidade em todos os tratamentos, possivelmente devido ao estresse causado pelo manuseio di?rio para vistoria da matura??o das g?nadas. Os resultados obtidos no presente estudo constataram a possibilidade de F. brasiliensis reproduzir em cativeiro em tanques pequenos, apresentando desempenho reprodutivo satisfat?rio. Por?m ? necess?rio reavaliar o manejo, para diminuir a mortalidade e melhorar a efici?ncia de c?pula, para otimizar o desempenho em cativeiro.

Orientadores: Telma Teixeira Franco, Sueli Rodrigues / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-19T11:18:02Z (GMT). No. of bitstreams: 1 Honorato_TalitaLopes_D.pdf: 6860909 bytes, checksum: 13811fc8b567923905d4a11f6cfd1a1a (MD5) Previous issue date: 2011 / Resumo: Estudos sobre quitina e quitosana têm atraído interesse devido à sua possível conversão em oligossacarídeos, que são solúveis em água e apresentam atraentes atividades biológicas. Para este fim, métodos eficazes para a produção de amino-oligossacarídeos (AGO's) potencialmente bioativos são necessários. O trabalho objetivou estudar a viabilidade de Fermentação em Estado Sólido (FES) para a produção de um extrato enzimático adequado para a obtenção de AGO's. Inicialmente foi identificado um fungo adequado para a FES utilizando cascas de camarão como substrato, sendo uma cepa de Trichoderma polysporum selecionada. A otimização das condições da fermentação para obtenção de um extrato enzimático capaz de produzir AGO's com grau de polimerização em torno de 5, grau de polimerização considerado o mínimo adequado para bioatividades foi realizada e as enzimas produzidas por T. polysporum sob diferentes condições de fermentação (submersa e sólida) foram analisados por eletroforese, seguida pela atividade de coloração e por atividades enzimáticas utilizando substratos cromogênicos específicos. Atividades enzimáticas de ß-N-acetilglucosaminidase, quitobiosidase e uma pequena quantidade de exo-quitinase e endo-quitinase foram observadas. O extrato da FES foi utilizado para degradar parcialmente diferentes quitosanas com fração molar de N-acetilglicosamina (FA) de valor 0,27 ou 0,56, e uma quitosana cormecial com FA em torno de 0,15. Os AGO's produzidos foram caracterizados por cromatografia em camada delgada e espectrometria de massa. Uma metodologia para separação de padrões oligoméricos acetilados e desacetilados por cromatografia líquida com detecção amperométrica pulsada dos oligossacarídeos foi desenvolvida e otimizou-se a hidrólise enzimática para produção dos AGO's de quitosanas. Hetero-oligômeros bioativos com grau de polimerização entre 2 e 7 foram produzidos, apresentando atividade antimicrobiana em Pseudomonas syringae e potencializando a explosão oxidativa em células de arroz, utilizando quitosana como elicitor (ambas atividades foram encontradas em concentrações de 50 µg/mL de AGO's) / Abstract: Studies on chitin and chitosan have drawn interest because of their possible conversion into oligosaccharides, which are water-soluble and present attractive biological activities. To this end, cost effective methods for the production of potentially bio-active chito-oligosaccharides (COS) are required. In this work we decided to study the feasibility of using solid state fermentation (SSF) for the production of a suitable enzyme extract for the eventual obtention of COS. The first step was the identification of a suitable fungus for solid satet fermentation (SSF) using shrimp shells as a substrate, and a strain of Trichoderma polysporum was eventually selected. The second step involved the optimisation of growth conditions to obtain enzyme preparations capable of producing COS with degrees of polymerisation of at least 5, this typically being the minimum DP for reliable bio-activities. The SSF extract was used to partially degrade different well characterised chitosans with a molar fraction of N-acetylglucosamine (FA) value of 0.27 or 0.56, and a commercial chitosan obtained from Sigma (FA around 0.15). The chitosanolytic enzymes produced by T. polysporum under different fermentation conditions were analysed by electrophoresis followed by activity staining and the enzyme activities of ß-N-acetylglucosaminidase, chitobiosidase and a small amount of exo-chitinase and endo-chitinase were observed. After hydrolysis, the complex mixture was precipitated, and the supernatant containing the COS produced was analysed using thin layer chromatography (TLC) and quadrupole time-of-flight tandem mass spectrometry. We detected the presence of chitinase rather than chitosanase activity and the production of hetero-oligomers with degrees of polymerisation between 2 and 7. The bio-activity of these oligomer mixtures in rice plants cells and against the growth of Pseudomonas syringae was founded / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

L’aquaculture de la crevette bleue Litopenaeus stylirostris représente une activité profitable enNouvelle-Calédonie. Cependant, elle doit faire face à deux maladies bactériennes saisonnières quidiminuent les rendements et menacent le développement aquacole. D'après la littérature, lapolyculture avec des poissons pourrait diminuer l'occurrence des maladies, prévenir la dégradation del'environnement et au final augmenter la production des bassins. Cette étude porte sur la faisabilitéd'élever en bassins L. stylirostris avec Siganus lineatus. Les objectifs majeurs ont été 1) d’estimer lacapacité de S. lineatus à s’adapter aux bassins et d’évaluer les performances de croissance, 2)d’estimer la faisabilité technique de la polyculture de L. stylirostris avec S. lineatus et 3) d’estimer leseffets de cette polyculture sur les performances zootechniques des deux espèces et sur lefonctionnement écologiques des bassins par comparaison avec leur monoculture.Pour répondre au premier objectif, Siganus lineatus (5.7g) a été mis en culture à des densités de 7, 14et 21 poissons.m-2 en système clos. Après 8 semaines de culture, les performances de croissance de S.lineatus ont été similaires quelles que soient les densités. S. lineatus peut donc bien s’adapter etcroître dans ces systèmes clos, même à des températures basses, proches de 20°C, et à forte densité.Les fortes densités n’ont pas eu d’effets négatifs sur la croissance, mais sont à l’origine d’unedétérioration des conditions environnementales suite à un apport plus marqué en aliment générantdavantage de déchets organiques. En conséquence, une mortalité de S. lineatus peut apparaître lorsquela concentration en oxygène descend en dessous des 2 mg.L-1.Pour atteindre le 2ème et le 3ème objectif, une seconde expérience a montré que l’ajout de S. lineatus(25.5 g) à une culture de crevettes (2.9 g; 15 crevettes.m-2) à des densités de 0, 1.2 et 2.4 poissons.m-2n’a pas affecté les performances zooetchniques de L. stylirostris sur cette première phase d'élevage.La survie de S. lineatus a été de 100% et sa croissance a été similaire quelle que soit sa densité. Laproduction combinée totale pour les traitements polyculture a augmenté de 47 – 106 % et les indicesde conversions diminuent de 31.6 – 47.7% en comparaison avec le traitement "monoculture decrevettes". L'ajout de S. Lineatus n'a pas eu d'effets significatifs sur la production primaire, larespiration, les flux dissous et particulaires à l'interface eau-sédiment de l'écosystème bassin.Dans une troisième expérience, avec des biomasses initiales plus élevées de L. stylirostris (14 g) de156 g.m-2 en polyculture avec S. lineatus (19 g) (80 g.m-2) et de 237 g.m-2 en monoculture, nous avonsobservé une forte mortalité des crevettes. Inversement, avec des biomasses initiales de S. lineatus (19g) de 155 g.m-2 en polyculture avec L. stylirostris (14 g) (81 g.m-2) et de 235 g.m-2 en monoculture,nous avons montré une augmentation de la biomasse de S. lineatus. En utilisant l'aliment pour sapropre croissance non utilisé par les crevettes, S. lineatus est ainsi capable de limiter l'impact dû àl'eutrophisation de l'écosystème bassin.Les résultats des analyses isotopiques montrent que l'aliment n'est pas une source majeure de carbonepour L. stylirostris et S. lineatus alors qu'il l'est pour l'azote. Le biotope, en y incluant la matièreorganique des sédiments et la matière organique particulaire dans la colonne d'eau est la principalesource de carbone pour les deux espèces et une source secondaire pour l'azote.Pour conclure, S. lineatus est un candidat potentiel pour la culture commerciale / Blue shrimp Litopenaeus stylirostris farming is a major and profitable activity of aquaculture industryin New Caledonia. However, it is facing two seasonal bacterial diseases, which decrease rearedshrimp yield and threaten the sustainability of the aquaculture development. As reported by theliterature, polyculture with fish would have the potential to decrease the impact of these kind ofdiseases, prevent the deterioration of the environment and to increase the production of the ponds. Thefeasibility of L. stylirostris and Siganus lineatus polyculture in earthen ponds was carried out in thisstudy. The main objectives were 1) to estimate the adaptive capacity and growth performance of S.lineatus, and the environmental variations in a closed culture system, 2) to estimate the technicalfeasibility of L. stylirostris and S. lineatus polyculture, and 3) to estimate the effects of L. stylirostrisand S. lineatus polyculture on zootechnical performances and pond ecology in comparison withmonoculture of these species.To answer to the first objective, Siganus lineatus (5.7g) was stocked at 7, 14 and 21 fish.m-2 in aclosed culture system. After 8 weeks of culture period, S. lineatus growth performance was similarbetween all densities. S. lineatus could well adapt and grow in a closed system, even at lowtemperature, ca. 20oC and high stocking density, 21 fish.m-2. High stocking density did not havenegative effects on S. lineatus growth performance, but could cause the environmental deteriorationdue to increased nutrient input and accumulated organic wastes in the culture system. Asconsequence, S. lineatus could die when water oxygen depleted to below 2 mg.L-1.To reach the second and the third objective, a second experiment showed that adding S. lineatus (25.5g) to L. stylirostris (2.9 g) culture system (15 shrimp.m-2) at 1.2 and 2.4 fish.m-2 did not affect L.stylirostris zootechnical performance during the first stage of the rearing. S. lineatus gained 100% ofsurvival and similar growth performance in all densities. The polyculture system increased totalcombined production by 47 – 106 % and reduced FCR by 31.6 – 47.7% compared with those inshrimp monoculture. The addition of S. lineatus to the culture system did not have significantlyeffects on the gross primary productivity, the respiration, the nutrient and particulates fluxes at thewater-sediment interface of the pond ecosystem.In a third experiment, using higher stocking biomasses of L. stylirostris (14 g) at 156 g.m-2 in apolyculture with S. lineatus (19 g) (80 g.m-2) and at 237 g.m-2 in shrimp monoculture, we observed ahigh shrimp mortality. Conversely, stocking biomasses of S. lineatus (19 g) at 155 g.m-2 in apolyculture with L. stylirostris (14 g) (81 g.m-2) and at 235 g.m-2 in monoculture resulted in increasesof S. lineatus biomasses. This study showed that polyculture using S. lineatus is able to reduce organicwastes and nutrient release by consumption uneaten feed and retention input nutrients in biomass thatcontribute to limit the impact of the pond ecosystem eutrophication.Results of stable isotope analyses showed that the used pellet feed was not a major carbon source, butwas an important nitrogen source for both L. stylirostris and S. lineatus. Natural biota, includingsediment organic matter and particulate organic matter, was a main carbon source and represented asa secondary nitrogen source for both species.It may be concluded that S. lineatus is a suitable candidate for commercial culture in bothmonoculture and polyculture with L. stylirostris in earthen pond. Polyculture should be a properapproach that could partly contribute to sustainable development of aquaculture, but needs specificresearch to optimize the trophic status of the reared species.

Le biofloc est un système d’élevage intensif avec un faible renouvellement d’eau ; ainsi se développe une population diversifiée de micro-organismes (micro-algues, zooplanctons et bactéries) associée à de la matière organique qui forme les floculats. Ces derniers jouent le double rôle de filtre biologique et de complément alimentaire. Cette thèse a pour objectif de mieux comprendre le fonctionnement de ce système d’élevage et ses interactions avec la crevette Litopenaeus stylirostris. Dans cet objectif général s’inscrit deux objectifs plus spécifiques : (i) mesurer les gains zootechniques apportés par l’élevage en biofloc (ii) étudier les interactions trophiques entre le milieu d’élevage et la crevette en lien avec les performances zootechniques. Nos résultats montrent des gains relatifs de l’élevage en biofloc aux niveaux de la survie, de la croissance, des performances de reproduction des femelles et de la qualité de leur progéniture. Ces meilleures performances s’expliquent par la contribution de la productivité naturelle, estimée entre 37 et 40%, dans l’alimentation de la crevette. Ce complément d’aliment, outre d’être toujours disponible dans le milieu d’élevage, apporte de l’énergie, des nutriments et des molécules bioactives. L’aliment naturel représente une source nutritive de lipides, particulièrement riche en phospholipides et en acides gras polyinsaturés, qui sont essentiels pour la reproduction et le développement des larves en phase de lécitotrophie ; ces lipides sont accumulés dans la glande digestive et les œufs des femelles élevées en biofloc. L’aliment naturel est également une source de glutathion, puissante molécule antioxydante, qui contribue au renforcement du système des défenses anti-radicalaires de la crevette et protège les lipides insaturés de la peroxydation, une cause du stress oxydant. Les bactéries sont prépondérantes dans la productivité naturelle d’un élevage en biofloc et contribuent donc à l’alimentation de la crevette. Aussi, dans le dernier volet de cette thèse, nous avons caractérisé la diversité taxonomique et l’abondance des bactéries du milieu d’élevage et montré son influence sur le microbiote intestinal des crevettes. De façon générale, nous observons une meilleure santé des animaux élevés en biofloc qui se traduit par une régulation positive des gènes impliqués dans l’immunité et les défenses anti-radicalaires après un stress au peroxyde d’hydrogène. Ainsi, les effets positifs de l’élevage en biofloc sur les survies, les croissances et la reproduction ont pour origine le complément d’aliment apporté par la productivité naturelle / Biofloc is an intensive rearing system with zero or minimal water exchange where a diverse population of microorganisms (microalgae, zooplankton and bacteria) develops in association with organic matter to form the floc particles. These particles play the double role of biological filter and dietary supplement. This dissertation aims to better understand the process of this rearing system and its interactions with the Litopenaeus stylirostris shrimp. Two specific objectives were integrated within the framework of this general objective: (i) to measure the production gain from biofloc rearing and (ii) to study the interaction between biofloc environment and shrimp and to assess its role on production performances of shrimps. Thus, our results show production gains of shrimp reared in biofloc in terms of survival, growth, reproductive performances and quality of larvae. This better performance can be explained by the contribution of natural productivity, estimated between 37 and 40%, in shrimp food. This food supplement, constantly available in the environment, provides energy, nutrients and bioactive molecules. The natural productivity represents a source of lipids, in particular of phospholipids and polyunsaturated fatty acids, which were essential for the reproduction and development of larvae during the lecitotrophic stage; these lipids were accumulated in digestive gland and eggs from females reared in biofloc. The natural food is also a glutathione source, a powerful antioxidant molecule, which contributes to strengthen antioxidant defense system of shrimps and protects lipids against peroxidation, a cause of oxidative stress. Bacteria were dominant in natural productivity of biofloc environment and contribute to shrimp food. Thus, in the last part of this dissertation, we characterized the taxonomic diversity and abundance of bacteria in biofloc environment and showed their influence on shrimp intestinal microbiota. Generally, we observed a better health of biofloc resulting in up-regulation of the studied genes involved in immunity and anti-radical defenses after oxidative stress with hydrogen peroxide. The positive effects of biofloc rearing on survival, growth and reproduction originate from food complement provided by natural productivity.

Establishing historical water velocities is a goal of Everglades restoration because of their role maintaining landscape topographic relief. However, flows may also change the trophic state of marshes by phosphorus loading. I used fatty acid (FA) and stoichiometric data to quantify how increased sheet flow altered the relative heterotrophic and autotrophic contributions to aquatic consumers in a field experiment that introduced flowing water to an Everglades marsh in November, 2014. Algal taxonomic composition was different between pre-flow and flow sampling, marked by increases in the nutrient exploiting Mougeotia species (green algae) during flow sampling. Dietary tracer FAs in consumers reflected changes in algal resources, including an increase in green algae-derived and a decrease in bacteria-derived FAs. These food web responses indicate that establishing historic water velocity in degraded wetlands can shift the origins of organic matter from a more detrital to more algal supported web.

Les processus de bioturbation constituent un exemple classique d’ingénierie de l’écosystème. Ils sont le fait d’espèces bioturbatrices qui contribuent à la structuration physique et biogéochimique des environnements sédimentaires. Dans les environnements marins meubles, les thalassinidés comptent parmi les bioturbateurs les plus influents. Ainsi, la crevette de vase Upogebia cf. pusilla est à l’origine d’un important remaniement sédimentaire et d’une large bioirrigation des sédiments dans le bassin d’Arcachon. Ces activités de bioturbation modulent les processus de minéralisation de la matière organique et les flux biogéochimiques à l’interface eau-sédiment. L’intensité de la bioturbation de U. cf. pusilla dépend de son état physiologique, celui-ci pouvant être altéré par divers facteurs de stress. Une approche couplant études de terrain et expérimentations en laboratoire a permis d’évaluer l’influence du parasitisme et de la contamination métallique sur les activités de U. cf. pusilla. Ce travail avait pour objectifs de (1) caractériser la pression parasitaire chez U. cf. pusilla à l’échelle locale, (2) déterminer les niveaux de base des éléments métalliques chez cet organisme dans le bassin d’Arcachon et d’évaluer le potentiel rôle des parasites dans les processus d’accumulation des métaux et (3) estimer l’impact du parasitisme et de la contamination métallique, seuls et en interaction, sur U. cf. pusilla et ce à deux échelles d’organisation, moléculaire et comportementale. In situ, un suivi spatial et un suivi temporel ont permis de caractériser la dynamique spatio-temporelle de deux parasites chez U. cf. pusilla¸ un bopyre infestant la cavité branchiale (Gyge branchialis), et un trématode (Maritrema sp.), infectant l’ensemble des organes de l’animal. Au sein de leur hôte, ces deux parasites sont négativement associés, le bopyre limitant probablement les processus d’infection par le trématode. Par ailleurs, un suivi saisonnier d’un an a permis de noter de faibles concentrations en métaux chez U. cf. pusilla, dans le bassin d’Arcachon. Ces concentrations ont été mises en parallèle avec le statut parasitaire des spécimens échantillonnés. Aucune corrélation n’a été notée entre la présence des trématodes et les quantités de métaux accumulées. A l’inverse, les observations de terrain ont permis d’envisager que le parasite bopyre puisse interférer avec les processus d’accumulation des métaux chez cet organisme. Cette dernière hypothèse a été testée en laboratoire au cours d’expérimentations visant à évaluer l’influence d’une contamination métallique (en utilisant le cadmium comme contaminant modèle) et du parasite bopyre, seuls et en interaction, sur U. cf. pusilla. A l’échelle moléculaire, le bopyre n’a été associé à aucune modification de l’expression d’une dizaine de gènes cibles. Par ailleurs, à l’échelle comportementale, ce parasite réduit peu le remaniement sédimentaire de son hôte, à l’inverse de ce qui avait été montré au cours d’une étude antérieure. En ce qui concerne l’influence du cadmium, ce métal module amplement l’expression de gènes codant notamment des protéines impliquées dans la réponse au stress oxydant et dans les mécanismes de détoxication. Ces observations suggèrent que U. cf. pusilla est capable de mettre en place des mécanismes de lutte contre le stress métallique. Au niveau comportemental, le cadmium semble stimuler le remaniement sédimentaire des organismes. Finalement, les expériences « doubles stress » ont montré un effet antagoniste du bopyre et du cadmium à la fois à l’échelle génique et à l’échelle comportementale. Ainsi, cette étude souligne la complexité des interactions entre facteurs de stress multiples et la nécessité d’effectuer de telles expérimentations. [...] / Bioturbation is a typical example of ecosystem engineering. Bioturbating species are mainly epi- or endobenthic organisms, which profoundly affect the physical structure and biogeochemical properties of sediments. In marine soft-bottom environments, thalassinidean mud shrimp are considered as one of the most prominent bioturbating organisms. Among these species is the mud shrimp Upogebia cf. pusilla, which is recognized as an important sediment reworker, also significantly contributing to the bioirrigation of sediments. In fine, this species greatly modulates organic matter mineralization and biogeochemical fluxes at the sediment-water interface. The influence of U. cf. pusilla in ecosystem functioning depends on the intensity of its bioturbation and thus on its fitness. Several factors can affect the physiological status of organisms, potentially resulting in behavioural changes and causing modifications of their activities. Amongst potential stressors, we evaluated the influence of parasitism and trace metal contamination on the mud shrimp U. cf. pusilla in Arcachon Bay, France. Field surveys and laboratory experiments were undertaken in order to evaluate (1) the parasite infestation levels in the mud shrimp at the local scale, (2) the metal contamination background and potential relationship between the metal accumulation and the parasitic status of organisms in the field and (3) estimate the distinct and interactive impacts of parasitism and metal contamination on two scales of organisation, by targeting a molecular (gene expression) and a behavioural (sediment reworking) endpoint.A large spatial and temporal survey conducted in Arcachon Bay showed that at least two parasites species occur in mud shrimp: a bopyrid isopod (Gyge branchialis), living in one of the gill chambers of its host, and a trematode parasite (Maritrema sp.), infecting the whole body of mud shrimp. These two parasite species are negatively associated within their host, in which the bopyrid likely interferes with trematodes establishment. Additionally, a one year seasonal sampling demonstrated that mud shrimp displayed very low levels of metals in Arcachon Bay. The bopyrid parasite could interfere with the process of metal accumulation in mud shrimp, while such correlation was not found for the trematode parasite. Finally, complementary laboratory experiments highlighted that, at the molecular level, the bopyrid parasite did not affect the expression of the genes targeted in this study in mud shrimp. Similarly, at the behavioural level, and conversely to a previous study, the effects of the bopyrid parasite were minor, i.e. only associated to small modifications of the bioturbation activity of its host. Indeed, the intensity of the sediment reworking of mud shrimp was slightly reduced when organisms were infested with this parasite. Regarding trace metal contamination, we noticed that mud shrimp largely accumulated cadmium. This accumulation was associated to an important modulation of gene expression, especially of genes encoding proteins involved in detoxification processes, highlighting, at this organisation level, the capability of mud shrimp to deal with the deleterious effect of cadmium. At the behavioural scale, cadmium contamination positively affected the sediment reworking activity of mud shrimp. Finally, double-stress experiments evidenced an antagonistic effect of both stressors on the two targeted endpoints. This study highlights the complexity of the interactions between multiple stressors and that the response of organisms cannot be predicted from “single-stress” experiments. [...]

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Phenotypic plasticity is the ability of an organism to express different phenotypes in response to biotic or abiotic environmental cues. The ability of an organism to make changes during development to adjust to changes in its environment is a key to survival. Sexually reproducing organisms that have short life cycles and that are easy to raise in the laboratory are more conducive for developmental phenotypic plasticity. Considerable research has already been carried out on the brine shrimp, Artemia franciscana, regarding its morphology due to changing salinities. There is, however, little research considering subsequent generations and how there morphology might be affected by parental experiences. This study has examined: 1) the morphological effects of different rearing regimes of different salinity levels, and 2) the epigenetic transgenerational transfer of these morphological traits in A. franciscana. Measurements included rate of growth (as measured by instar), body size, body length, and other morphological traits. A gradual increase to more hyperosmotic conditions during development produced brine shrimp that were larger in size and also more developmentally advanced. Salinity stress experienced by adults had increased the growth rate in the F1 offspring of A. franciscana. Collectively, these data indicate that Artemia franciscana is a tractable model for investigating phenotypic plasticity. These findings have added to the ever-growing field of developmental phenotypic plasticity while also providing more information on the natural history and adaptive abilities of A. franciscana.

Reconhecendo-se a susceptibilidade do camarão à autólise e à decomposição microbiana, a presente pesquisa teve como objetivo avaliar a influência de diferentes doses de radiação gama na qualidade da carne, sob os aspectos microbiológicos, físicoquímicos e sensoriais durante o armazenamento sob refrigeração do camarão-brancodo- pacífico (Litopenaeus vannamei). As amostras foram constituídas de camarões in natura, sem o cefalotórax, acondicionados em bandejas de poliestireno, embalados em filme plástico flexível e submetidos a diferentes doses de radiação gama (1,0 e 3,5 kGy), sendo que estas foram mantidas sob refrigeração (5ºC ± 1ºC) e analisadas no 1º, 7º, 14º e 21º dias de armazenamento. Foram realizadas análises microbiológicas (Staphylococcus coagulase positiva, Salmonella ssp, Coliformes totais e termotolerantes, microrganismos psicrotróficos e mesófilos), e testes físico-químicos: bases nitrogenadas voláteis totais (BNVT), pH, nitrogênio não protéico (NNP), análise de TBARS - substâncias reativas ao ácido tiobarbitúrico (TBA) e trimetilamina (TMA), além de determinações de colesterol e composição centesimal. Foram realizadas análises para cor (instrumental) e para aceitabilidade (hedônico), visando à determinação da qualidade sensorial do camarão (submetido à cocção) durante o período de armazenamento. Verificou-se que o processo de irradiação reduziu a população bacteriana inicial e após o armazenamento as amostras irradiadas apresentaram-se dentro dos padrões previstos pela legislação brasileira (BRASIL, 2005b). Já as amostras não irradiadas, após o 7º dia de armazenamento, estavam impróprias para o consumo por extrapolarem o limite estabelecido para Staphylococcus. Foram encontrados valores de 6,05 a 6,39 para pH; 19,47 a 80,84 mg/100g para BNVT; 2,61 a 12,85 mg/100g para TMA; 0,22 a 1,20 mg de malonaldeído/1000g para TBA e 53,09 a 134,81 mg/100g para colesterol. As amostras irradiadas mantiveram-se estáveis durante o período de armazenamento, o que não ocorreu nas amostras não irradiadas, quanto ao pH, índices de BNVT e TMA. A irradiação resultou na redução do teor de colesterol e valores de TBA nos diferentes tempos avaliados. Não houve diferença (p <=0,05) para cor instrumental no primeiro dia de armazenamento, em relação a amostras não irradiadas e irradiadas com 3,5 kGy. Não foram detectadas diferenças estatísticas (p <= 0,05) no aspecto sensorial entre amostras irradiadas e não irradiadas no 1º dia de armazenamento. As amostras não irradiadas foram rejeitadas sensorialmente a partir do 7º dia de armazenamento, enquanto que as amostras irradiadas com 1 kGy foram aceitas até o 14º dia. As amostras irradiadas com 3,5 kGy mantiveram-se com aroma e aparência adequados até o final do experimento. Concluiu-se que o uso da radiação gama, especialmente a dose de 3,5 kGy, proporcionou maior estabilidade físico-química e segurança microbiológica durante o armazenamento, em relação ao produto refrigerado convencional, sem ocasionar alteração na qualidade sensorial do camarão. A radiação gama assegurou maior vida útil ao camarão refrigerado, atingindo 21 dias de armazenamento, sendo, portanto, um coadjuvante recomendável. / Taking into account shrimp susceptibility to autolise and bacterial decomposition, this study aimed to evaluate the different gamma irradiation dosis influence over meat quality related to microbiological, physical-chemical, nutritional and sensorial aspects, during cold storage of the white shrimp (Litopenaeus vannamei). Samples were taken from fresh shrimps without cephalothoraxes, settled into poliestirene trays, packed with flexible plastic film and submitted to different dosis of gamma irradiation (1.0 and 3.5 kGy). Samples were kept under refrigeration (5ºC 1ºC) and analyzed at the 1st, 7th 14th and 21st day of storage. Microbiological analyzes were realized (Coagulase-positive Staphylococcus, Salmonella ssp, coliforms, psychrotrophic and mesophilic population), and physical-chemical and tests (Total volatile bases (TVNB), pH, non proteic nitrogen (NNP), TBARS analysis - reactive substances to tiobarbituric acid (TBA), trimetilamine (TMA) cholesterol teor and proximate composition). Instrumental color test were realized and hedonic test was taken to determine cooked products sensorial quality during storing period. It was noticed that the irradiation process reduced bacterial population and during storage all the irradiated samples were under the patterns established by the Brazilian legislation (BRAZIL, 2005a). Non-irradiated samples were inappropriate for consumption after one week of storage, since they were over Staphylococcus established limits. The pH values ranged from 6.05 to 6.39; 19.47 to 80.84 mg.100g-1 for TVNB; 2.61 to 12.85 mg.100g-1 for TMA-N; 0.22 a 1.20 mg of malonaldeide.1000g-1 for TBA and 53.09 to 134.81 mg.100g-1 for cholesterol concentrations. Irradiated samples kept more stability during storage period when compared to non-irradiated samples, regarding to pH, TVNB and TMA levels. Samples irradiation resulted into cholesterol and TBA values reduction at different evaluated moments. No significant differences (p <= 0.05) were found in terms of instrumental color during the first day of storing when compared to the non-irradiated samples and to the 3.5 kGy irradiated ones. Statistical differences were not found (p <= 0.05) between non-irradiated and irradiated samples within the first day of sensorial analysis. Non-irradiated samples were rejected on the sensorial test after the 7th day of storage, while the 1kGy irradiated samples were accepted until the 14th day. Samples irirradiated with 3.5 kGy kept viability in terms off flavour and aspect until the end of the experiment. When compared to conventional refrigerated product, the gamma-irradiation technique, (especially the 3.5 kGy dosis) provided a higher stability related to physicalchemical properties and microbiological safety during storage. No differences on the sensorial shrimp quality were found. Through gamma irradiation, we obtained a product with minimal procedure modifications, with enhanced shelf life under refrigeration.