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| Registros recuperados: 15 | |
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| Merchie, G.; Lavens, P.; Dhert, Ph.; Garcia Ulloa Gómez, M.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.. |
| The effect of the high ascorbic acid (AA) levels transferred through enriched live food was evaluated for turbot <i>Scophthalmus maximus</i> larvae in two consecutive feeding experiments. The same feeding strategy was applied to all treatments, except for the AA content in the live food which was manipulated through bioencapsulation with ascorbyl palmitate. This resulted finally in a low, medium and high-AA treatment. The AA incorporation levels in the turbot larvae (up to 1400 µg AA g DW<sup>-1</sup>) were correlated with the AA content of the live food administered. However, feeding the high AA concentration resulted in the same values as for the medium treatment, indicating a saturation of the body AA reserves. Under standard... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1996 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3022 |
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| Merchie, G.; Kontara, E.K.M.; Lavens, P.; Robles, R.; Kurmaly, K.; Sorgeloos, P.. |
| Postlarvae of tiger shrimp, <i>Penaeus monodon</i> (Fabricius), were fed semipurified diets supplemented with various levels of astaxanthin (AX) and ascorbic acid-polyphosphate (ApP): three groups were fed 230 mg AX kg<sup>-1</sup> diet combined with 100, 1700 and 3400 mg ascorbic acid (AA) kg<sup>-1</sup> diet, respectively; two diets contained 810 mg AX kg<sup>-1</sup> mixed with 200 and 1700 mg AA kg<sup>-1</sup>, respectively. Each treatment was run in four replicates. Incorporated levels of AA and AX, production output, and physiological condition were recorded after 4 weeks feeding. Whole-body AA (21-47 µg<sup>-1</sup>) and AX concentrations (19-35 µg<sup>-1</sup>)... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Penaeus monodon [giant tiger prawn]. |
| Ano: 1998 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=312 |
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| Merchie, G.; Lavens, P.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.. |
| A study was undertaken to upgrade the levels of vitamin C in <i>Artemia</i> and <i>Brachionus</i> through bioencapsulation and to investigate in this way the requirements for ascorbic acid (AA) during larviculture of fish and prawn. Ascorbyl palmitate (AP) was used as the vit C source because of its stable and lipophylic characteristics which allowed its incorporation in booster emulsions and its readily conversion into AA by <i>Brachionus</i> and <i>Artemia</i> . Under standard conditions very high levels of AA could be incorporated into the <i>Artemia</i> nauplii: supplementation of the enrichment emulsion with 20% AP (w/w) increased the AA-content up to 2000 ppm after 24h enrichment. Also in... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1993 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2743 |
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| Merchie, G.; Lavens, P.; Sorgeloos, P.. |
| In order to assess the dietary needs for ascorbic acid (AA) at startfeeding, the AA content in the various live diets currently applied in aquaculture (algae, rotifers, <i>Artemia</i> ) was studied. Application of boosting techniques using ascorbyl palmitate (AP) as the vitamin C source enabled the transfer of elevated levels of bioactive vitamin C (up to 2500µg AA.g DW<sup>-1</sup>) via the live food chain into larvae of fish (<i>Clarias gariepinus, Dicentrarchus labrax, Scophthalmus maximus</i>), shrimp (<i>Pennaeus vannamei</i>) and prawn (<i>Macrobrachium rosenbergii</i>). This vitamin C enrichment procedure has proven to be a valuable technique, especially for the evaluation of the effects of... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1995 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2587 |
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| Merchie, G.; Lavens, P.; Radull, J.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.. |
| The effects of high levels of ascorbic acid (AA) delivered through enriched live food has been verified through the successful culture of larval giant freshwater prawn, <i>Macrobrachium rosenbergii</i> Two successive feeding trials were set up using a control (550 µg AA g<sup>-1</sup> DW) and two different AA-enrichment levels in <i>Artemia</i> (1300 and 2750 µg AA g<sup>-1</sup> DW). Under standard culture conditions, no differences in growth nor survival could be observed demonstrating that the nutritional requirements are below 550 µg AA g<sup>-1</sup> DW, which is the normal level occurring in freshly-hatched <i>Artemia</i> . However, a significantly positive effect could be... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Artemia. |
| Ano: 1995 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2582 |
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| Kontara, E.K.M.; Merchie, G.; Lavens, P.; Robles, R.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.. |
| L-ascorbyl-2-polyphosphate (ApP) was used as a vitamin C source to study the ascorbic acid (AA) requirements for the early postlarval stages of white shrimp (<i>Penaeus vannamei</i>). First the stability of ApP in the diets was determined: ApP losses after pelletizing and 10 min immersion in seawater were 25-35% and 30%, respectively. Semipurified diets with five levels of ApP (0, 20, 40, 100 and 200 mg kg<sup>-1</sup> expressed as active AA were fed <i>ad libitum</i> to <i>P. vannamei</i> (PL-14 stage, mean dry weight 0.73 mg) for 26 days. Each treatment was run in five replicates. No significant differences in growth were observed among treatments after 26 days of feeding. As of day 19 of feeding, increased... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diets; Polyunsaturated fatty acids; Shrimp culture; Penaeus vannamei. |
| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2959 |
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| Merchie, G.; Lavens, P.; Storch, V.; Übel, U.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.. |
| Stable forms of vitamin C were verified as dietary sources of ascorbic acid (AA) for the nursery stages of European sea bass and turbot. In a first experiment, various concentrations of ascorbyl palmitate (AP) and one level of AA 2-polyphosphate (ApP) were evaluated in a semi purified diet for European sea bass, <i>Dicentrarchus labrax</i>. A significantly lower AA concentration was detected in the fry fed the AP-supplemented diets compared to the ApP-fed group, providing evidence that AP is an inferior source of vitamin C for young stages of sea bass. ApP was subsequently selected for the determination of the AA requirements of both sea bass and turbot (<i>Scophthalmus maximus</i>) fry. The AA levels incorporated in the body... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dicentrarchus labrax (Linnaeus; 1758) [Bass] Scophthalmus maximus (Linneaus; 1758). |
| Ano: 1996 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3045 |
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| Merchie, G.; Lavens, P.; Dhert, Ph.; Pector, R.; Mai Soni, A.F.; Nelis, H.; Ollevier, F.P.; De Leenheer, A.P.; Sorgeloos, P.. |
| Live food enrichment techniques, using formulated diets and emulsions for improving the nutritional quality of <i>Brachionus</i> and <i>Artemia</i> , were studied as a tool for transferring ascorbic acid (AA) to fish larvae. <i>Artemia</i> nauplii enriched for 24h with an experimental emulsion containing 20% HUFA and 0%, 10% and 20% ascorbyl palmitate (AP) were administered to catfish larvae in a 20-day feeding trial. Survival was not affected by the dietary AA, but from day 7 onwards a significantly positive effect of supplemental AA on growth was demonstrated. At the end of the experiment the 20% AP group weighed 30% more than the control (0% AP), i.e. 9.5 and 6.3mg DW, respectively. Evaluation of the physiological... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Clarias gariepinus Dicentrarchus labrax (Linnaeus; 1758) [Bass]. |
| Ano: 1995 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2581 |
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| Merchie, G.; Lavens, P.; Sorgeloos, P.. |
| HPLC techniques were adapted and standardized for quantification of ascorbic acid (AA) and its derivates in both diets and target organisms. To assess the dietary needs for AA at start of exogenous feeding, the AA content in the various live diets currently used in aquaculture (algae, rotifers, <i>Artemia</i> ) was analyzed. Application of techniques for boosting vitamin C using ascorbyl palmitate as the source enabled the transfer of elevated levels (up to 2,500 µg AA/g DW) of bioactive vitamin C. Larvae of fish (<i>Clarias gariepinus, Dicentrarchus labrax, Scophthalmus maximus</i>), white shrimp (<i>Penaeus vannamei</i>) and prawn (<i>Macrobrachium rosenbergii</i>) were enriched via the live food chain.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Crustacean larvae; Diets; Vitamin C. |
| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2962 |
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| Nelis, H.J.; Merchie, G.; Lavens, P.; Sorgeloos, P.; De Leenheer, A.P.. |
| Two producers are described for the solid-phase extraction of ascorbic acid 2-sulfate from cysts of the brine shrimp <i>Artemia</i> . The first one is based on reversed-phase ion pair extraction on an octadecylsilica cartridge using tetrabutylammonium as the counterion, followed by elution with methanol. In the second procedure ascorbic acid 2-sulfate is retained on a DEAE silica cartridge and eluted with 0.1M sodium salicylate. Both approaches were used as part of a quantitative reversed-phase ion pair liquid chromatographic method with detection at 254nm. The anion exchange extraction procedure is superior to its ion pair counterpart in terms of recovery (88.7±3,5% versus 63.0±12.7%), reproducibility (CVs of 3.6-7.7% versus 6.3-18.7%), and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Artemia franciscana. |
| Ano: 1994 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2643 |
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| Merchie, G.; Lavens, P.; Verreth, J.; Ollevier, F.P.; Nelis, H.; De Leenheer, A.P.; Storch, V.; Sorgeloos, P.. |
| The effect of three dietary ascorbic acid (AA) concentrations, each applied via two feed types, on production characteristics and physiological condition of African catfish (<i>Clarius gariepinus</i>) larvae has been assessed in two 10-day culture trials. Three treatments received only <i>Artemia</i> nauplii enriched with an experimental emulsion containing 0, 10 or 20% ascorbyl palmitate (AP) and yielding 530, 1200 and 1600 µg AA g<sup>-1</sup> DW <i>Artemia</i> , respectively; the other three treatments were fed the same <i>Artemia</i> diets which were partially substituted by an artificial diet containing no vitamin C (ratio 20:80). No differences in survival could be observed: however, from... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish larvae; Food organisms; Vitamin C; Clarias gariepinus. |
| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2963 |
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| Merchie, G.; Lavens, P.; Dhert, Ph.; Dehasque, M.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.. |
| Ascorbic acid (AA) is an essential nutrient in particle and live aquafeeds. In order to better assess the needs for this nutrient during larviculture the AA content of algae, rotifers and <i>Artemia</i> was studied with respect to their suitability at startfeeding. In general, the microalgae evaluated were rich in AA (1000-4000 µgAA/gDW), but showed a considerable variability among the different species: e.g. the concentration in <i>Isochrysis</i> and<i>Chlorella</i> reached values 3-to 4-fold the percentage of <i>Tetraselmis</i> (0.11% of DW). <i>Brachionus</i> routinely cultured on <i>Chlorella</i> contained 2300 µg AA/gDW. Cysts of various batches and strains of... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1995 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2578 |
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| Registros recuperados: 15 | |
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