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Endotrophic Larvae (endotrophic + larva)
Selected AbstractsFatty acid nutritional quality of sea urchin Paracentrotus lividus (Lamarck 1816) eggs and endotrophic larvae: relevance for feeding of marine larval fishAQUACULTURE NUTRITION, Issue 4 2009J.M. GAGO Abstract Sea urchin eggs and larvae have been suggested as potential live prey for marine fish larval feeding. This study evaluated the fatty acid composition of Paracentrotus lividus eggs, prisms and four-armed plutei, obtained from wild and captive broodstocks fed on raw diets: maize, seaweed and a combination of maize and seaweed. Amounts of essential fatty acids (EFA) for marine fish larvae [arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA)] were determined in eggs and endotrophic larvae. ARA ranged from 3.93% in eggs from combination to 18.7% in plutei from maize diets. In any developmental stage, EPA amounts were always lower than 5% for the raw diets, and DHA showed null or trace amounts including the wild diet. Thus, broodstock-prepared diets had to be formulated based on different lipid sources (Algamac, linseed oil, cod liver oil and olive oil) in order to test eggs and larvae EFA enhancement. EFA improvement was possible for all tested prepared diets. Algamac diet lead to superior EFA enhancement mainly in DHA (7.24%, 4.92% and 6.09% for eggs, prisms and plutei, respectively) followed by cod liver oil diet. Only these two lipid sources should be considered for prepared broodstock diets in order to obtain suitable live prey for fish larval feeding. [source] Survival and growth of selected marine fish larvae first fed with eggs and endotrophic larvae of the sea urchin Paracentrotus lividusAQUACULTURE RESEARCH, Issue 9 2010Joćo Gago Abstract Two sets of experiments were carried out to evaluate the potential of eggs and endotrophic larvae of captive Paracentrotus lividus as alternative live prey for marine fish larvae first feeding. The first consisted in rearing sparids, Diplodus sargus and Sparus aurata, larvae until 15 days after hatching in a recirculation system. Compared with the commonly used live prey , rotifer Brachionus spp. , general lower values of survival and growth were obtained when fish larvae were fed with the alternative live prey. Among these, eggs showed to be the preferred feeding. Broodstock feed showed to play a fundamental role on prey quality and consequent fish larvae survival. In the second set of experiments, the 24-h ingestions of the first feeding larvae in static water were determined for five currently cultured fish larvae species. Except for larger and more predatory Dicentrarchus labrax larvae, there was a trend for higher P. lividus egg ingestion, followed by pre-plutei and prisms. Prey size, colour and movement affected food selection by fish larvae. It is concluded that, in spite of the alternative live prey being readily consumed by all tested fish larvae, they cannot however presently compete with rotifers in marine fish larvae first feeding. [source] |