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One of the selected species for the diversification of traditional marine species is the wreckfish Polyprion americanus due to its growth potential, high larval growth index during its pelagic life phase (Kentouri et al 1995, Papandroulakis et al 1997), the quality of its flesh and its high commercial value. Studies on wreckfish nutritional requirements and optimum diets are missing. There are only a few references related to feeding habitats from commercial caught (Brick Peres & Haimovi, 2003) and feeding rates in captivity (Papandroulakis et al., 2004) . Recently a study about composition of Mediterranean Sea wreckfish was published (Roncarati et al.,2014). The aim of this work is collecting information of the composition of different tissues of wild wreckfish to contribute the development of a specific formulation of a diet for wreckfish broodstock., DIVERSIFY

Probiotics are currently being supplemented to cultured fish due to their benefits for fish performance. Herein, we tested the health protection and nutritional effects of probiotic Shewanella putrefaciens (Pdp11 strain), both fresh and lyophilized cells, on Senegalese sole (Solea senegalensis) juveniles. Pdp11 was incorporated into fish feed at concentration of 109 cells g−1, and then provided to juvenile sole for 2 months. Growth rates were significantly higher in fish fed the fresh probiotic compared with fish fed the control diet. Growth of fish receiving lyophilized bacteria was not improved when compared with controls. Body compositions (protein, total lipids and fatty acids profile) were similar for each dietary treatment. At the end of the study, fish were challenged by intraperitoneal inoculation with a pathogenic strain of Photobacterium damselae subsp. piscicida. Relative percentages of survival (RPS) ranged between 25% and 43.8% for fish receiving both probiotic supplemented diets. Both fresh and lyophilized Pdp11 cells conferred protection against P. damselae subsp. piscicida. However, only fresh Pdp11 enhanced Senegal sole performance. These findings should be taken into account for industry purposes in which lyophilized Pdp11 might be easier to manage., Sí

The growth performance and flesh quality of Senegalese sole (Solea senegalensis) fed two practical diets, in which 78% of marine-derived protein was replaced by plant protein ingredients (PP), was compared with those fed a commercial diet (control) from Skretting (57% protein, 18% lipids; dry matter basis). All tested diets were isonitrogenous, but PP diets contained two lipid levels: 9% (PP-9) and 18% (PP-18). PP diets were produced by Sparos S.L. The experiment was conducted in a closed circuit system at the experimental facilities of IGAFA (heated seawater:1930 ).Triplicate groups of 30 pig-tagged fish, born in captivity, with an average weight of 64,09and size16,42were distributed by 9 tanks of 1m2 and fed the experimental diets during 5 months. Analyses of total lipids were carried out. The results were compared by a Studentt-test and one-way ANOVA . By the end of the trial the growth performance of the fish varied significantly among dietary treatments. Fish fed with PP-9 grew better than those fed PP-18, having a final body weight similar to that obtained with the commercial diet (Fig.1). Whole body lipid composition of the fish differed among treatments (Table I). Plant protein diets induced a significantly lower whole body lipid deposition (7-8% ww) than those fed the control (9% ww). This was reflected in lipid distribution among tissues. Lipid levels in the muscle of the commercial fish are significantly higher than in those fed with PP-9. In contrast, the liver lipid content was significantly increased when plant-protein diets were used compared to fish fed the control, confirming previous observation in the pre-fattening phase of sole (Linares et al. WAS2011). Sensory analyses showed that fish from all the tested treatments shared similar texture, odour and taste characteristics. The present results confirm that with low fat diets it is quite feasible to use plant-protein sources without affecting the growth performance or the organoleptic quality of Senegalese sole. Nevertheless, the impact of the increased lipid deposition in liver induced by vegetable sources warrants further studies.

During one month, paralarvae of common octopus (Octopus vulgaris) were fed 3 different diets: (1) Artemia sp. enriched with Isochrysis galbana (AI) complemented with sand eel (Hyperoplus lanceolatus) flakes (AH); (2) Artemia sp. enriched with crushed marine zooplankton (AZ); and (3) Artemia sp. cultured with Isochrysis galbana and further enriched with the microalga Nannochloropsis sp. (AN). The highest dry weight (1.6179±0.3861 mg) was registered with the AN diet and the best average survival (67.0%) with the AZ diet. Considering the highest dry weight obtained, the moderate high survival and the fact that with this diet it was possible to attain the adult stage, the AN diet was the most appropriate. The reasons for the best result in growth observed with AN are discussed as: (1) the combination of docosahexaenoic acid (DHA) provided by Isochrysis galbana and the high eicosapentaenoic acid (EPA) content present in Nannochloropsis sp.; (2) the fact that the higher protein/lipid ratio of this diet improves the final dry weight of the paralarvae; and (3) the fact that Nannochloropsis sp. could inhibit the harmful microflora growth in the rearing tank. Regarding nutritional aspects, DHA content per se is not the only determinant factor for growth and survival of O. vulgaris paralarvae, but the presence of a high protein/lipid ratio and a high phospholipid content in the diet could possibly explain the better quality and strength of the paralarvae., Paralarvas de pulpo común (Octopus vulgaris) fueron alimentadas, durante un mes, con tres dietas diferentes: (1) Artemia sp. enriquecida con Isochrysis galbana (AI) complementada con laminillas de lanzón (Hyperoplus lanceolatus) congelado (AH); (2) Artemia sp. enriquecida con zooplancton marino congelado (AZ) y (3) Artemia sp. cultivada con Isochrysis galbana y posteriormente enriquecida con la microalga Nannochloropsis sp. (AN). El peso seco más alto (1.6179±0.3861 mg) fue registrado con la dieta AN y la mejor supervivencia media (67.0%) con la dieta AZ. La dieta AN fue la más apropiada teniendo en cuenta el peso seco más alto, la supervivencia moderadamente elevada y el hecho de que con esta dieta fue posible alcanzar el estadio adulto. Se discuten las causas del mejor resultado de crecimiento observado con AN: (1) la combinación de DHA proporcionada por Isochrysis galbana y el alto contenido en EPA presente en Nannochloropsis sp.; (2) el ratio proteínas/lípidos más elevado de esta dieta puede mejorar el peso seco final de las paralarvas; y (3) es posible que Nannochloropsis sp. inhiba el crecimiento de microflora dañina en el tanque de cultivo. Con respecto a los aspectos nutricionales, el contenido en DHA per se no es el único factor determinante para el crecimiento y supervivencia de paralarvas de O. vulgaris, pero la presencia de un ratio proteínas/lípidos alto y un elevado contenido en fosfolípidos en la dieta podría determinar la mejor calidad y fortaleza de las paralarvas.