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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efeito da intensificação na larvicultura do camarão-da-malásia Macrobrachium rosenbergii /

David, Fernanda Seles. January 2011 (has links)
Resumo: Avaliou-se o efeito da densidade de estocagem na larvicultura de Macrobrachium rosenbergii nas densidades de 50, 70, 80, 90, 100, 120 e 140 larvas/L. Os custos de implantação, de produção e os indicadores econômicos de três larviculturas hipotéticas utilizando densidades de estocagem de 50, 100 e 140 larvas/L foram avaliados. Os resultados obtidos mostram que a intensificação do sistema influenciou as variáveis sobrevivência e produtividade. Nas densidades mais elevadas, os valores de produtividade foram maiores, todavia, a partir de 90 larvas/L o espaço demonstrou-se um fator limitante, afetando a quantidade de indivíduos na população sem comprometer o desenvolvimento das larvas. Na análise econômica, o cultivo na densidade de 140 larvas/L apresentou os melhores indicadores econômicos e suportou melhor as possíveis variações de mercado. No entanto, a densidade de 100 larvas/L apresentou indicadores próximos aos obtidos para 140 larvas/L, maior eficiência na taxa de metamorfose e pode gerar menor nível de estresse nas larvas. Conclui-se que o intervalo de 90 a 100 larvas/L é mais adequado, biológica e economicamente, para a produção de pós-larvas de M. rosenbergii, em sistema fechado dinâmico / Abstract: We evaluated the effect of stocking density on larval rearing of Macrobrachium rosenbergii in stocking densities of 50, 70, 80, 90, 100, 120 and 140 larvae/L. The costs of planting, production and economic indicators using three hypothetical hatcheries stocking densities of 50, 100 and 140 larvae/L were evaluated. The results obtained show that the intensification of the system influences the survival and productivity variables. At higher densities, the productivity values were greater, however, from 90 larvae/L the space proved to be a limiting factor, affecting the amount of individuals in the population without compromising the development of larvae. In economic analysis, the rearing in density of 140 larvae/L showed the best economic indicators and endured the best possible market variations. However, the density of 100 larvae/L showed indicators close to those obtained for 140 larvae/L, more efficient rate of metamorphosis and can lead to lower stress levels in the larvae. We conclude that the range of 90 to 100 larvae/L is more appropriate, biological and economically, to produce post-larvae of M. rosenbergii, in a closed system dynamic / Orientador: Wagner Cotroni Valenti / Coorientador: Alessandra da Silva Augusto / Banca: Margarete Mallasen / Banca: Ricardo Jorge Guerra Calado / Mestre
2

Efeito da intensificação na larvicultura do camarão-da-malásia Macrobrachium rosenbergii

David, Fernanda Seles [UNESP] 16 June 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-16Bitstream added on 2014-06-13T19:27:40Z : No. of bitstreams: 1 david_fs_me_jabo.pdf: 1823187 bytes, checksum: 5487fdb6b27e5848e23858c636cfd1b2 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Avaliou-se o efeito da densidade de estocagem na larvicultura de Macrobrachium rosenbergii nas densidades de 50, 70, 80, 90, 100, 120 e 140 larvas/L. Os custos de implantação, de produção e os indicadores econômicos de três larviculturas hipotéticas utilizando densidades de estocagem de 50, 100 e 140 larvas/L foram avaliados. Os resultados obtidos mostram que a intensificação do sistema influenciou as variáveis sobrevivência e produtividade. Nas densidades mais elevadas, os valores de produtividade foram maiores, todavia, a partir de 90 larvas/L o espaço demonstrou-se um fator limitante, afetando a quantidade de indivíduos na população sem comprometer o desenvolvimento das larvas. Na análise econômica, o cultivo na densidade de 140 larvas/L apresentou os melhores indicadores econômicos e suportou melhor as possíveis variações de mercado. No entanto, a densidade de 100 larvas/L apresentou indicadores próximos aos obtidos para 140 larvas/L, maior eficiência na taxa de metamorfose e pode gerar menor nível de estresse nas larvas. Conclui-se que o intervalo de 90 a 100 larvas/L é mais adequado, biológica e economicamente, para a produção de pós-larvas de M. rosenbergii, em sistema fechado dinâmico / We evaluated the effect of stocking density on larval rearing of Macrobrachium rosenbergii in stocking densities of 50, 70, 80, 90, 100, 120 and 140 larvae/L. The costs of planting, production and economic indicators using three hypothetical hatcheries stocking densities of 50, 100 and 140 larvae/L were evaluated. The results obtained show that the intensification of the system influences the survival and productivity variables. At higher densities, the productivity values were greater, however, from 90 larvae/L the space proved to be a limiting factor, affecting the amount of individuals in the population without compromising the development of larvae. In economic analysis, the rearing in density of 140 larvae/L showed the best economic indicators and endured the best possible market variations. However, the density of 100 larvae/L showed indicators close to those obtained for 140 larvae/L, more efficient rate of metamorphosis and can lead to lower stress levels in the larvae. We conclude that the range of 90 to 100 larvae/L is more appropriate, biological and economically, to produce post-larvae of M. rosenbergii, in a closed system dynamic
3

Investigations into the reproductive performance and larval rearing of the Brown shrimp, Farfantepenaeus aztecus, using closed recirculating systems

Gandy, Ryan Leighton 17 February 2005 (has links)
The effects of unilateral eyestalk ablation, diets and sex ratios were evaluated on two wild populations of Farfantepenaeus aztecus in a closed recirculating maturation system. Ovarian development and spawning frequencies of ablated females in both studies were higher than the non-ablated females. Replacement of bloodworms in maturation diet with enriched adult Artemia sp. had no negative effect on the number of eggs spawned and resulted in increased hatch and survival rates from Nauplius I to Zoea I. Life span of ablated females fed enriched Artemia sp. was longer than ablated females fed bloodworms. Replacement of the expensive bloodworm diet component with adult enriched Artemia sp. is possible without negative impact on female reproductive performance. Reducing male to female ratio from 2:1 to 1:1 resulted in a 1.25% decrease in spawning activities of ablated females. The life cycle of pond-raised F1 generation F. aztecus also was completed in the closed recirculating system using unilateral eyestalk ablation as previously described. This study found diets that contained an enriched adult Artemia sp. component performed superior (i.e. hatch rate, nauplii and zoea production) to a diet containing bloodworms. Six consecutive larval rearing trials evaluated changes in select water quality indicators and their effect on growth, survival, and stress tolerance of F. aztecus postlarvae cultured in artificial seawater under closed recirculating and flow-through conditions. The closed recirculating larval rearing system successfully produced five-day-old postlarvae (PL) from Zoea I (Z1) with similar dry weights, lengths and stress resistance to PL produced under standard water exchange practices. The trickling biofilters were found to be a limiting component of this system. A submerged coral biofilter was added to the system and effectively processed culture water for re-use. Addition of the submerged biofilter resulted in improved survival rates in Trials 4, 5 and 6. These studies demonstrate maturation and larval rearing of F. aztecus is feasible in closed recirculating systems. Implementation of these systems in hatcheries bolsters biosecurity while reducing the environmental impact of hatchery effluent. Recirculating and re-use systems are therefore essential in the further development of sustainable hatchery programs for endemic species.
4

Husbandry and larval rearing of common snook (Centropomus undecimalis)

Yanes-Roca, Carlos January 2006 (has links)
Common snook (Centropomus undecimalis) is a relatively new species for aquaculture; considered as a recreational species and not commercial. The aim of this study was to develop common snook larval rearing techniques for stock enhancement. Common snook culture has two main bottlenecks, broodstock management and larval culture. High mortality during the first 6 days is the main limitation for successful larval survival. Broodstock management of common snook is still developing and the only source of common snook eggs is from wild broodstock. Securing a regular supply during the natural spawning was essential to reach the main objective. Finding the optimal spawning sites, as well as optimal spawning time was achieved. Results showed Terra Ceia, Longboat and Cayo Costa to be the best sites for wild broodstock collection. The onset of spawning was triggered by a rise in water temperature. During the 4 years of this study spawning started at the end of May and finished in September. Total capture results and egg quality results, such as fertilization, hatching rate and lipid analysis, indicated June and July as the peak months during the spawning season. Common snook follow a lunar spawning cycle. Results showed that one to three days after the new and full moon were the peak spawning periods and therefore the best days to capture wild stock. Common snook egg lipid composition fits the general marine fish fatty acid composition with saturated fatty acids predominating. On the other hand, the omega 3, omega 6 (n-3/n-6) ratio was lower than the typical marine fish and arachidonic acid values were significantly higher than other marine species. This egg fatty acid profile will be helpful in the future to compare it with captive spawned eggs for egg quality purposes. Description of the common snook embryonic and larval development for the first 14 days was carried out. This has strengthened knowledge for this species’ development, and should provide a helpful tool to identify common snook embryos and larvae in the wild. Novel improvements to existing common snook larval culture protocols were implemented. Larval lipid analysis throughout development, and high mortality around day 6 post hatching, suggested that common snook larvae were dying of starvation. Gross morphological development and ultra-structure findings in the digestive and eye system development during the first three days indicated that day 2 post hatching larvae were capable of capturing and digesting food. Additionally, larval nutritional improvements were made, increasing the larval survival. The most significant ones were: finding a smaller and more nutritional prey (SS type rotifers and copepods), finding an optimal stocking and feeding density and the importance that green water technique has on larval survival. Overall, larval success was improved from a zero percent survival during the first 14 days to a 2% survival rate.
5

Reprodução, desenvolvimento embrionário e larvicultura do “neon goby” Elacatinus Figaro em laboratório

Shei, Marcelo Roberto Pereira January 2008 (has links)
Dissertação(mestrado)-Universidade Federal do Rio Grande, Programa de Pós-Graduação em Aqüicultura, Instituto de Oceanografia, 2008. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2012-07-22T21:55:11Z No. of bitstreams: 1 dissertaao shei.pdf: 955699 bytes, checksum: 8f9882265e94129eca93eb60bbe7cdf7 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-07-27T19:09:22Z (GMT) No. of bitstreams: 1 dissertaao shei.pdf: 955699 bytes, checksum: 8f9882265e94129eca93eb60bbe7cdf7 (MD5) / Made available in DSpace on 2012-07-27T19:09:22Z (GMT). No. of bitstreams: 1 dissertaao shei.pdf: 955699 bytes, checksum: 8f9882265e94129eca93eb60bbe7cdf7 (MD5) Previous issue date: 2008 / O “neon goby” Elacatinus figaro é endêmico da costa brasileira e foi uma das espécies mais importantes no comércio de peixes ornamentais marinhos do país. Atualmente, encontra-se na lista de espécies ameaçadas de extinção e resguardadas do extrativismo. Este trabalho teve como intuito descrever a reprodução, o desenvolvimento embrionário e a larvicultura do “neon goby” em laboratório. As primeiras desovas naturais foram observadas a partir do 24° dia após a formação dos casais, sendo o intervalo entre as desovas de 8 a 10 dias a 26°C. A fecundidade variou de 430 a 1.020 ovos por desova com média de 648 ± 183 ovos (média ± desvio padrão1, com taxa de eclosão média de 69 ± 16% Os ovos são elípticos, medem 1,81 ± 0,1 mm de comprimento e 0,61 ± 0,03 mm de diâmetro, eles apresentam filamentos adesivos na parte basal e contêm cinco protuberâncias na parte distal. O tempo para eclosão das larvas é de 7 a 8 dias. As larvas recém eclodidas medem 3,15 ± 0,07 mm, apresentam fototaxia positiva, olhos pigmentados, boca aberta e vesícula gasosa inflada. As larvas foram alimentadas com rotíferos Brachionus plicatilis em sistema de água verde com a microalga Nannochloropsis oculata do 1° ao 20° dia após a eclosão. Náuplios de Artemia foram oferecidos a partir do 15 ° dia em conjunto com rotíferos e, exclusivamente, a partir do 20° dia. O assentamento ocorreu a partir do 28° dia, quando as larvas do “neon goby” atingiram comprimento de 8,50 ± 0,18 mm com sobrevivência entre 2 e 20%. / The “neon goby” Elacatinus figaro is endemic of the Brazilian coast and was one of the most important species in the marine ornamental fish trade in the country. Today it is on the list of endangered species and it can no longer be collected in the wild. This work was carried out in order to describe natural breeding, embryonic development and larviculture of neon goby in laboratory. The first natural spawning was observed 24 days after the pairs were formed 8 to 10 days at 26°C. Mean fecundity was 648 ± 183 (± SD) eggs per clutch and ranged from 430 to 1020 eggs, the hatching rate was 69 ± 16%. Eggs are elliptical in shape, they present adhesive filaments at the proximal end and five protuberances at the distal end. Egg length averaged 1.81 ± 0.1 mm and maximum width was 0.61 ± 0.03 mm. The embryonic developmental period lasts between 7 and 8 days. The newly hatched larvae measure 3.15 ± 0.07 mm, showing positive phototaxis, pigmented eyes, mouth opened and insufflated gas bladder. Larvae were fed with rotifers Brachionus plicatilis in green water system along with the microalgae Nannochloropsis oculata from day 1 to day 20 day after hatching. Artemia nauplii were added to the diet on day 15, and 5 days later rotifers were no longer offered. Larvae began to settle to the bottom on day 28, when length of neon goby was 8.50 ± 0.18 mm, the final survival rate ranged between 2 and 20%.
6

Investigações morfológicas e metabólicas ao longo da ontogenia das larvas da garoupa verdadeira Epinephelus marginatus (Teleostei: Serranidae) / Morphological and metabolic investigations during the ontogeny of dusky grouper Epinephelus marginatus (Teleostei: Serranidae) larvae

Paulo Henrique de Mello 26 October 2015 (has links)
O presente projeto analisou o perfil dos ácidos graxos, embriogênese e ontogenia do sistema digestório das larvas da garoupa verdadeira Epinephelus marginatus durante os primeiros dias de desenvolvimento. Além disso, descrevemos como os embriões se dividem, eclodem e desenvolvem suas principais características, e como se desenvolve seu sistema digestório ao longo dos primeiros dias de desenvolvimento, e como utilizam os AG durante os primeiros 8 dias de desenvolvimento. Observamos que as larvas da garoupa apresentam desenvolvimento de suas estruturas digestórias relativamente lento, no entanto, estas são capazes de capturar, ingerir e digerir presas já a partir do 4º DAE. Os ovos da garoupa verdadeira são compostos por elevados percentuais de PUFA nos fosfolipídios e para o processo de eclosão utilizam preferencialmente os SFA dos fosfolipídios. Além disso, os PUFA da série n3 sobrepõe-se aos da série n6, principalmente o DHA, que apresentaram valores elevados em comparação com outras espécies marinhas tanto nos fosfolipídios quanto nos triglicérides nos três primeiros dias de desenvolvimento. As larvas apresentam uma elevada necessidade dos HUFAs DHA/EPA, e durante essa fase é importante a utilização de alimento vivo de tamanho reduzido (copépodes ou “SS strain” Brachionus rotundiformes) enriquecidos com valores da relação entre DHA/EPA acima de 2,0. Com isso, todo o conhecimento gerado durante esses dias de desenvolvimento já permitem a aplicação deste conhecimento no processo de embriogênese e larvicultura da garoupa verdadeira contribuindo para alavancar sua domesticação e produção em cativeiro e elaborar futuramente um programa de repovoamento desta espécie contribuindo para sua conservação. / This project analyzed the fatty acids profile, embryogenesis and ontogeny of the digestive system of dusky grouper Epinephelus marginatus larvae during the first days of development. Furthermore, we described how the embryos are divided, hatch and develop its main features, and how develops its digestive system during the first days of development, and how they use the FA during the first 8 days of development. We observed that the grouper larvae present relative slow development of their digestive structures, however, the larvae are able to capture, ingest and digest preys already from 4º DAE. The dusky grouper eggs are composed by high percentages of PUFA in phospholipids and for the hatching process it uses preferably the SFA of phospholipids. Additionally, the n3 series PUFAs overlaps the n6 series, especially DHA, which exhibited high values compared to other marine species both on phospholipids as in the triglycerides during the first three days of development. The larvae exhibit a high requirement of HUFAs DHA/EPA, and during this phase is important to use live food of small size (copepods or “SS strain” Brachionus rotundiformes) enriched with the ratio of DHA/EPA levels above 2.0. Thus, all the knowledge generated during these days of development allow us the application of this knowledge in the embryogenesis and hatchery process of the dusky grouper contributing to leverage its domestication and production in captivity and eventually draw up a restocking program of this species contributing to their conservation.
7

Investigações morfológicas e metabólicas ao longo da ontogenia das larvas da garoupa verdadeira Epinephelus marginatus (Teleostei: Serranidae) / Morphological and metabolic investigations during the ontogeny of dusky grouper Epinephelus marginatus (Teleostei: Serranidae) larvae

Mello, Paulo Henrique de 26 October 2015 (has links)
O presente projeto analisou o perfil dos ácidos graxos, embriogênese e ontogenia do sistema digestório das larvas da garoupa verdadeira Epinephelus marginatus durante os primeiros dias de desenvolvimento. Além disso, descrevemos como os embriões se dividem, eclodem e desenvolvem suas principais características, e como se desenvolve seu sistema digestório ao longo dos primeiros dias de desenvolvimento, e como utilizam os AG durante os primeiros 8 dias de desenvolvimento. Observamos que as larvas da garoupa apresentam desenvolvimento de suas estruturas digestórias relativamente lento, no entanto, estas são capazes de capturar, ingerir e digerir presas já a partir do 4º DAE. Os ovos da garoupa verdadeira são compostos por elevados percentuais de PUFA nos fosfolipídios e para o processo de eclosão utilizam preferencialmente os SFA dos fosfolipídios. Além disso, os PUFA da série n3 sobrepõe-se aos da série n6, principalmente o DHA, que apresentaram valores elevados em comparação com outras espécies marinhas tanto nos fosfolipídios quanto nos triglicérides nos três primeiros dias de desenvolvimento. As larvas apresentam uma elevada necessidade dos HUFAs DHA/EPA, e durante essa fase é importante a utilização de alimento vivo de tamanho reduzido (copépodes ou “SS strain” Brachionus rotundiformes) enriquecidos com valores da relação entre DHA/EPA acima de 2,0. Com isso, todo o conhecimento gerado durante esses dias de desenvolvimento já permitem a aplicação deste conhecimento no processo de embriogênese e larvicultura da garoupa verdadeira contribuindo para alavancar sua domesticação e produção em cativeiro e elaborar futuramente um programa de repovoamento desta espécie contribuindo para sua conservação. / This project analyzed the fatty acids profile, embryogenesis and ontogeny of the digestive system of dusky grouper Epinephelus marginatus larvae during the first days of development. Furthermore, we described how the embryos are divided, hatch and develop its main features, and how develops its digestive system during the first days of development, and how they use the FA during the first 8 days of development. We observed that the grouper larvae present relative slow development of their digestive structures, however, the larvae are able to capture, ingest and digest preys already from 4º DAE. The dusky grouper eggs are composed by high percentages of PUFA in phospholipids and for the hatching process it uses preferably the SFA of phospholipids. Additionally, the n3 series PUFAs overlaps the n6 series, especially DHA, which exhibited high values compared to other marine species both on phospholipids as in the triglycerides during the first three days of development. The larvae exhibit a high requirement of HUFAs DHA/EPA, and during this phase is important to use live food of small size (copepods or “SS strain” Brachionus rotundiformes) enriched with the ratio of DHA/EPA levels above 2.0. Thus, all the knowledge generated during these days of development allow us the application of this knowledge in the embryogenesis and hatchery process of the dusky grouper contributing to leverage its domestication and production in captivity and eventually draw up a restocking program of this species contributing to their conservation.
8

Invasion dynamics of a non-indigenous bivalve, Nuttallia obscurata, (Reeve 1857), in the Northeast Pacific

Dudas, Sarah 31 December 2005 (has links)
This thesis describes how life history characteristics of the varnish clam (Nuttallia obscurata), and interactions with the physical environment and other species, have contributed to its successful invasion in coastal British Columbia. Lab and field experiments were conducted to investigate varnish clam larval ecology (i.e. larval rearing experiments), adult population dynamics (i.e. annual population surveys, mark-recapture and length-frequency analysis, growth modeling) and ecological interactions with native species (i.e. predator/prey preference feeding trials). Using these results, a matrix demographic model was developed to determine which life history stage contributes the most to varnish clam population growth. Larval rearing experiments indicated that temperature and salinity tolerances of varnish clam larvae are comparable to native species, however the planktonic phase is slightly longer (3-8 weeks). Based on local oceanographic circulation, varnish clam larvae have the potential to disperse throughout their entire geographic range in just one reproductive season. Varnish clam population surveys revealed spatiotemporal variation in density and size. No relationships were evident between varnish clam density and the number or density of co-occurring bivalve species. Length-frequency analysis suggested that recruitment varies among sites, with high post-settlement mortality coinciding with high recruitment. The presence of similar recruitment pulses at geographically separate sites indicates regional scale processes may influence recruitment. Individual growth rates iii varied among sites, with higher growth corresponding to lower population densities and water temperature. Monthly survival rates ranged from 0.81 – 0.99 and were lower for clams 10-30 mm. Predator/prey preference feeding trials showed that crabs prefer varnish clams to local species when clam burial depth is limited. Crabs therefore have the potential to influence varnish clam distributions, particularly on beaches where the varnish clam is unable to bury deeply. Based on matrix demographic analysis, adult survival (e.g. clams ≥ 40 mm) is the most crucial factor for varnish clam population growth, and drives the observed population growth differences between sites. This study of the varnish clam invasion demonstrates that its success lies in both species (e.g. lengthy planktonic phase, high survival) and regional (e.g. favourable ocean circulation patterns for rapid dispersal) characteristics. Measures to reduce introductions should be targeted in areas where introductions are likely to have the furthest reaching impacts.
9

La sensibilité des larves de pectinidés aux conditions d'élevage : le flux ouvert comme alternative aux mortalités massives / The susceptibility of pectinids larvae to farming conditions : open flow as an alternative to mass mortalities

Holbach, Marine 19 December 2014 (has links)
Dans de nombreux pays, l’aquaculture de pectinidés dépend aujourd’hui du succès de la production contrôlée de juvéniles. Néanmoins, les fortes variations des taux d’éclosion des oeufs et de la survie larvaire, enregistrées à ce jour, rendent cette production imprévisible. Les élevages larvaires en flux ouvert de coquilles Saint-Jacques (Pecten maximus) ont été développés en Norvège et présentent des résultats prometteurs. Malheureusement, les rendements de production encore faibles et l’impossibilité de travailler à fortes densités restent un frein majeur au développement de cette technique. En France, une technique en flux-ouvert, en petit volume (5 L), et à forte densité (≤ 300 larves mL-1) a été développée pour les ostréidés. Des expériences préliminaires visant à décliner ce système d’élevage aux larves de P. maximus se sont avérées infructueuses : retard de croissance et forte mortalité en quelques jours. Il est reconnu que les larves de pectinidés doivent faire face à des contraintes diverses en écloserie : bactériologiques, physiologiques et environnementales. Elles sont également plus sensibles que les larves des autres espèces de bivalves comme par exemple l’huître japonaise (Crassostrea gigas). Il apparait donc nécessaire aujourd’hui d’identifier plus clairement l’origine des phénomènes perturbant le bon développement des larves en flux ouvert afin d’améliorer la qualité des élevages et les rendements larvaires. Grâce à l’étude et à la compréhension des mécanismes physiologiques impliqués dans la lutte contre le stress des larves de P. maximus en flux ouvert, ce projet de doctorat donne des clés permettant d’améliorer cette technique d’élevage tout en limitant l’utilisation de produits chimiques en milieu contrôlé. / In many countries, aquaculture of pectinids depends on the success of artificial spat production in hatchery. This production is always unpredictable due to the variability of hatching rate and larval survival. Flow-through larval rearing systems were developed in Norway for the King scallop Pecten maximus and showed promising results. Unfortunately the system needs to be optimized since the larval yields and the densities used are still relatively low. In France, a small-scale (5 L) and high-density (≤ 300 larva mL-1) flow-through larval rearing system was successfully developed for oysters. First trials in such system and in similar conditions with P.maximus failed as we registered slower growth and high mortality rate in only a few days. It is known that pectinids larvae are more sensitive to environmental conditions than the oyster Crassostrea gigas, for example.Nowadays, it is important to identify and to understand the phenomena disturbing larval development in flowthrough system to improve larval quality and production yields. This doctoral project provided some indications how improving P. maximus flowthrough rearing system while limiting the use of antibiotic through a better understanding the physiological mechanisms involved in the larval response to a stressful environment

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