Browsing by Author "De Vareilles, M."
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Inclusion of protein hydrolysates in the diet of white seabream (Diplodus sargus) larvae: impacts on skeleton quality and larvae proteome expressionPublication . Richard, Nadège; De Vareilles, M.; Gavaia, Paulo J.; Silva, Tomé S.; Cordeiro, O.; Yúfera, M.; Rodrigues, Pedro; Conceição, L. E. C.In order to investigate the effects of dietary protein hydrolysate on larval skeleton quality and larvae proteome expression, triplicate groups of white seabream (Diplodus sargus) larvae were co-fed from first-feeding onwards with live feed and three microencapsulated diets ir differing only on the molecular weight of their protein hydrolysate fraction.
- Metabolic molecular indicators of chronic stress in gilthead seabream (Sparus aurata) using comparative proteomicsPublication . Alves, Ricardo N.; Cordeiro, O.; Silva, Tomé S.; Richard, Nadège; De Vareilles, M.; Marino, G.; Di Marco, Patrizia; Rodrigues, Pedro; Conceição, L. E. C.The aim of this study was to identify possible metabolic molecular indicators of chronic stress in gilthead sea bream Sparus aurata. Two potential stressful conditions were tested: repeated handling and crowding at high stocking density. Gilthead seabream kept under optimized rearing conditions were used as control fish. Cortisol was measured as primary stress indicator and the liver proteome of stressed fish was compared to that of control fish using comparative proteomics. Plasma cortisol levels in sea bream repeatedly handled and crowded at high stocking density were significantly higher than in undisturbed control fish. A total of 560 spots were detected and the statistical analysis revealed a differential expression in about 50% of all detected proteins. Spots with greater than 2-fold or lower than 0.5-fold changes were identified by liquid chromatography–tandem mass spectrometry (LC–MS/MS). Proteins like fatty acid binding protein (lipid transport and antioxidant role), heat shock cognate protein (chaperoning), calmodulin (Ca2+ signaling), mitochondrial porine — voltage-dependent anion channel (lipid oxidation), glutamine synthetase (ammonia metabolism), cofilin and beta-tubulin (cytoskeleton), hemoglobin and several other proteins involved in carbohydrate metabolism (triose-phosphate isomerase, pyruvate dehydrogenase, glyceraldehyde 3-phosphate dehydrogenase, alfa-enolase) were differentially expressed in fish under chronic stress. Some of these proteins may be used in the future as chronic stress and/or part of a panel of welfare biomarkers, after validation studies using RT-PCR and ELISA assays.
- Proteomics as a tool to develop molecular indicators of nutritional condition in farmed gilthead seabreamPublication . Rodrigues, Pedro; Richard, Nadège; De Vareilles, M.; Silva, Tomé S.; Conceição, L. E. C.Gilthead seabream is the main aquaculture species produced in Portugal, as well as in the Mediterranean. However, the winter disease syndrome, a series of metabolic and immune system disorders caused by low temperatures, affects seabream culture, leading to important industrial losses, either as mortalities or growth decreases during spring. These effects can be minimized through dietary optimisation, either improving diets for the end of summer season, or feeding seabream with a fortified diet during autumn/winter. However, the development of a fortified diet for autumn/winter is hindered by the lack of tools to evaluate fish metabolic and physiological condition. Nevertheless, the recent development of new generation molecular tools provides good perspectives to supply molecular indicators of condition that would support this task.
- Two-dimensional proteomics as a tool to evaluate nutritional effects in farmed fishPublication . Richard, Nadège; Gavaia, Paulo J.; De Vareilles, M.; Silva, Tomé S.; Cordeiro, O.; Rodrigues, Pedro; Conceição, L. E. C.The use of proteomics in fish research is at a relatively early stage compared to terrestrial vertebrates. It has already been applied in the field of fish nutrition, enabling to point out metabolic changes occurring in response to dietary manipulations such as a variation in energy content, dietary nitrogen compostion, lipid composition or the incorporation of plant protein sources in aquafeeds.