61 research outputs found

    Nutrition, quality and performance in marine fish larvae

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    O cultivo de larvas de peixes marinhos é caracterizado por altas mortalidades e por problemas de qualidade, nomeadamente malformações esqueléticas. A solução de parte destes problemas passa por uma melhor compreensão dos requisitos nutricionais. Este trabalho pretende fazer uma revisão de trabalhos recentes que demonstram como os aminoácidos, os ácidos gordos e a vitamina K, mas também o regime alimentar, podem influenciar a qualidade e a performance das larvas de peixes marinhos

    New data on opisthobranchs (Mollusca: Gastropoda) from the southwestern coast of Portugal

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    The present papers reports the results obtained from different field samplings carried out on the southwestern Portuguese coast during July 2002, within the scope of three research projects on opisthobranch molluscs. Two areas were sampled, one around Sagres (37° 00' N, 8° 57' W) on the SW tip of the Portuguese mainland, the other near Sines (37° 57' N, 8° 53' W), 110 km north of the other site. Eighty-one species of opisthobranchs were identified, six of them new to the Portuguese fauna.Se exponen los resultados obtenidos a partir de los diferentes muestreos realizados en julio de 2002 en el suroeste de la costa portuguesa, en el ámbito de tres proyectos centrados en los moluscos opistobranquios. Se muestrearon dos áreas: una en los alrededores de Sagres (37° 00' N, 8° 57' O), en el extremo suroeste continental de Portugal y la otra en los alrededores de Sines (37° 57' N, 8° 53' O), a 110 km al norte de la primera. Se identificaron 81 especies de opistobranquios, seis de las cuales constituyen nuevas citas para la fauna portuguesa.Instituto Español de Oceanografí

    An annotated and updated checklist of the ophsthobranchs ((Mollusca: Gastropoda) from Spain and Portugal (including islands and archipelagos)

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    The present publication is a new annotated and updated checklist of the opisthobranchs (Mollusca, Gastropoda) from the Spanish and Portuguese coasts, including their Atlantic archipelagos (Azores, Madeira, Selvagens and Canary Islands). The bathyal species recorded from the continental shelf of all these areas are also included. Incorporating a review of the literature, 523 species are included on the present checklist, 23 belonging to Architectibranchia, 111 to Cephalaspidea s. s., 14 to Anaspidea, 4 to Acochlidiomorpha, 37 to Thecosomata, 7 to Gymnosomata, 43 to Sacoglossa, 3 to Umbraculoidea, 16 to Pleurobranchoidea and 265 to Nudibranchia: 127 Doridoidea, 42 Dendronotoidea, 9 Arminoidea, and 87 Aeolidoidea. The records these species have been divided into 12 geographic sectors: 1) Spanish coast on the Bay of Biscay; 2) Galicia; 3) mainland coast of Portugal; 4) Andalusian Atlantic coast; 5) Straits of Gibraltar, including Ceuta (northern Africa); 6) Andalusian Mediterranean coast, ..

    Effect of variable levels of dietary cholesterol and plant sterols on the growth performance and bone metabolism in gilthead seabream (Sparus aurata) juveniles

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    Cholesterol is found in all animal tissues and is an important component of biological cell membranes with functions such as precursor to bile acids, hormones and vitamins. Fish meal and fish oil are cholesterol-rich ingredients. Replacement of these marine-derived ingredients by plant proteins and vegetable oils tends to reduce dietary cholesterol levels

    Determinism and causative factors for morphological anomalies in reared European fishes

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    The presence of sublethal morphological deformities represents one of the main bottleneck of the industrial finfish hatchery production, resulting in major economic loss due to reduced growth and marketing ability of the final product, that has to be transformed (filets) or sold for fish flour. Furthermore, the elimination of deformed fishes from the productive cycle needs for periodic selections at present carried out by manual sorting. This represents an additional economic cost, and a stress for fishes

    Skeletal quality in Senegalese sole: characterization of fish resulting from environmental and nutritional trials

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    The Senegalese sole (Solea senegalensis) is characteristic from southern Europe and Mediterranean. It has recently been adapted for aquaculture production since it is well accepted by consumers and reaches high commercial values. After the initial description of the ontogenic events of skeletogenesis, systematic evaluation of the incidence of skeletal malformations by several groups revealed high levels of skeletal deformities reaching up to 90% of the population

    Two isoforms of vasa maternal factor in Senegalese sole: Biotechnological applications

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    Primordial Germ Cells (PGCs) identification and manipulation present considerable potential for hatchery practice and surrogate broodstocks. To carry out the PGCs characterization a specific molecular marker is required. The vasa gene is a good candidate to identify PGCs and others germinal cells (Nagasawa et al., 2009). The aim of this study was the cloning of the Solea senegalensis vasa cDNA and its expression pattern during early development and adulthood

    Dietary beauvericin and enniatin B exposure cause different adverse health effects in farmed Atlantic salmon

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    The extensive use of plant ingredients in novel aquafeeds have introduced mycotoxins to the farming of seafood. The emerging enniatin B (ENNB) and beauvericin (BEA) mycotoxins have been found in the novel aquafeeds and farmed fish. Little is known about the potential toxicity of ENNs and BEA in farmed fish and their feed-to-organ transfer. Atlantic salmon (Salmo salar) presmolt (75.3 +/- 8.10 g) were fed four graded levels of spiked chemical pure ENNB or BEA feeds for three months, in triplicate tanks. Organismal adverse health end-point assessment included intestinal function (protein digestibility), disturbed hematology (red blood cell formation), bone formation (spinal deformity), overall energy use (feed utilization), and lipid oxidative status (vitamin E). Both dietary BEA and ENNB had a low ( liver > brain > muscle), with a higher transfer for ENNB compared to BEA. BEA caused a growth reduction combined with a decreased protein digestion and feed conversion rate-ENNB caused a stunted growth, unrelated to feed utilization capacity. In addition, ENNB caused anemia while BEA gave an oxidative stress response. Lower bench-mark dose regression assessment showed that high background levels of ENNB in commercial salmon feed could pose a risk for animal health, but not in the case of BEA.Grant 281032 HAVBRUK2;info:eu-repo/semantics/publishedVersio

    Matrix gla protein in turbot (Scophthalmus maximus): gene expression analysis and identification of sites of protein accumulation

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    Matrix Gla protein (Mgp) is a secreted vitamin K-dependent extracellular matrix protein and a physiological inhibitor of calcification whose gene structure, amino acid sequence and tissue distribution have been conserved throughout evolution. In the present work, the turbot (Scophthalmus maximus) mgp cDNA was cloned and the sequence of the deduced protein compared to that of other vertebrates. As expected, it was closer to teleosts than to other vertebrate groups but there was a strict conservation of amino-acids thought to be important for protein function. Analysis of mgp gene expression indicated branchial arches as the site with higher levels of expression, followed by heart, vertebra and kidney. These results were confirmed by in situ hybridization with a strong mgp expression in branchial arch chondrocytes. Mgp was found to accumulate in gills where it appeared to be restricted to chondrocytes from branchial filaments, while in vertebrae it was localized in vertebral end plates, in growth zones, in vertebral arches and spines and in notochord cells. In the soft tissues analysed, Mgp was mainly detected in kidney and heart, consistent with previous data and providing further evidence for a role of Mgp as a calcification inhibitor and a modulator of the mineralization process. Our studies provide evidence that turbot, an important new species for aquaculture, is also a useful model to study function and expression of Mgp

    Matrix gla protein in xenopus laevis: molecular cloning, tissue distribution, and evolutionary considerations

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    Matrix Gla protein (MGP) belongs to the family of vitamin K-dependent, Gla-containing proteins and in higher vertebrates, is found in the extracellular matrix of mineralized tissues and soft tissues. MGP synthesis is highly regulated at the transcription and posttranscription levels and is now known to be involved in the regulation of extracellular matrix calcification and maintenance of cartilage and soft tissue integrity during growth and development. However, its mode of action at the molecular level remains unknown. Because there is a large degree of conservation between amino,acid sequences of shark and human MGP, the function of MGP probably has been conserved throughout evolution. Given the complexity of the mammalian system, the study of MGP in a lower vertebrate might be advantageous to relate the onset of MGP expression with specific events during development. Toward this goal, MGP was purified from Xenopus long bones and its N-terminal amino acid sequence was determined and used to clone the Xenopus MGP complementary DNA (cDNA) by a mixture of reverse-transcription (RT)- and 5'- rapid amplification of cDNA ends (RACE)-polymerase chain reaction (PCR). MGP messenger RNA (mRNA) was present in all tissues analyzed although predominantly expressed in Xenopus bone and heart and its presence was detected early in development at the onset of chondrocranium development and long before the appearance of the first calcified structures and metamorphosis. These results show that in this system, as in mammals, MGP may be required to delay or prevent mineralization of cartilage and soft tissues during the early stages of development and indicate that Xenopus is an adequate model organism to further study MGP function during growth and development.NATO/CRG940751/SA5.2.05, Praxis XXI/BIA 469/94, (NIH; grant AR 25921) (Praxis XXI/BPD/18816) (Praxis XXI/BICJ-2985
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