Consulta: creatorFacets:"Nelis, H."
Registros recuperados: 18
Data/hora: 15/06/2024 16:09:16

Drug assimilation in the tissue of European sea bass (&lt;i&gt;Dicentrarchus labrax&lt;/i&gt;) fry delivered orally through bioencapsulation
Provedor de dados: 27
Autores: Gapasin, R.S.J.; Nelis, H.; Chair, M.; Sorgeloos, P.
Assimilation levels of the antibacterials trimethoprim (TMP) and sulfamethoxazole (SMX) in sea bass (&lt;i&gt;Dicentrarchus labrax&lt;/i&gt;) fry tissue administered orally were investigated. A 1:5 TMP and SMX combination incorporated in oil emulsion (Selco) at 20% and 40% concentrations (w/w) were bioencapsulated in &lt;i&gt;Artemia&lt;/i&gt; (Instar II) nauplii. Chemotherapeutics-loaded ('medicated') nauplii were fed to the sea bass fry and drug concentration in the tissue were analysed by high-performance liquid chromatography (HPLC). Fish fed 40% 'medicated' &lt;i&gt;Artemia&lt;/i&gt; assimilated significantly higher levels of chemotherapeutics compared with those fed 20% 'medicated' &lt;i&gt;Artemia&lt;/i&gt; . Chemotherapeutics given at 40% reached...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Dicentrarchus labrax (Linnaeus; 1758) [Bass].
Ano: 1996
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2964

Improved larviculture outputs of postlarval shrimp &lt;i&gt;Penaeus vannamei&lt;/i&gt; through supplementation of L-ascorbyl-2-polyphosphate in the diet
Provedor de dados: 27
Autores: Kontara, E.K.M.; Merchie, G.; Lavens, P.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Penaeus vannamei.
Ano: 1995
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2572

Variation of ascorbic acid content in different live food organisms
Provedor de dados: 27
Autores: 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 &lt;i&gt;Artemia&lt;/i&gt; 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 &lt;i&gt;Isochrysis&lt;/i&gt; and&lt;i&gt;Chlorella&lt;/i&gt; reached values 3-to 4-fold the percentage of &lt;i&gt;Tetraselmis&lt;/i&gt; (0.11% of DW). &lt;i&gt;Brachionus&lt;/i&gt; routinely cultured on &lt;i&gt;Chlorella&lt;/i&gt; contained 2300 µg AA/gDW. Cysts of various batches and strains of...
Tipo: Info:eu-repo/semantics/article
Ano: 1995
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2578

Evaluation of vitamin C-enriched &lt;i&gt;Artemia&lt;/i&gt; nauplii for larvae of the giant freshwater prawn
Provedor de dados: 27
Autores: 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, &lt;i&gt;Macrobrachium rosenbergii&lt;/i&gt; Two successive feeding trials were set up using a control (550 µg AA g&lt;sup&gt;-1&lt;/sup&gt; DW) and two different AA-enrichment levels in &lt;i&gt;Artemia&lt;/i&gt; (1300 and 2750 µg AA g&lt;sup&gt;-1&lt;/sup&gt; 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&lt;sup&gt;-1&lt;/sup&gt; DW, which is the normal level occurring in freshly-hatched &lt;i&gt;Artemia&lt;/i&gt; . 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

Live food mediated vitamin C transfer to &lt;i&gt;Dicentrarchus labrax&lt;/i&gt;and &lt;i&gt;Clarias gariepinus&lt;/i&gt;
Provedor de dados: 27
Autores: 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 &lt;i&gt;Brachionus&lt;/i&gt; and &lt;i&gt;Artemia&lt;/i&gt; , were studied as a tool for transferring ascorbic acid (AA) to fish larvae. &lt;i&gt;Artemia&lt;/i&gt; 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

Effect of vitamin C incorporation in live food on the larviculture success of aquaculture species
Provedor de dados: 27
Autores: Merchie, G.; Lavens, P.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.
A study was undertaken to upgrade the levels of vitamin C in &lt;i&gt;Artemia&lt;/i&gt; and &lt;i&gt;Brachionus&lt;/i&gt; 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 &lt;i&gt;Brachionus&lt;/i&gt; and &lt;i&gt;Artemia&lt;/i&gt; . Under standard conditions very high levels of AA could be incorporated into the &lt;i&gt;Artemia&lt;/i&gt; 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
Ano: 1993
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2743

An oral challenge for turbot larvae with &lt;i&gt;Vibrio anguillarum&lt;/i&gt;
Provedor de dados: 27
Autores: Chair, M.; Dehasque, M.; Van Poucke, S.; Nelis, H.; Sorgeloos, P.; De Leenheer, A.P.
There is a need for a standard in vitro procedure to infect larval fish with bacteria. Such a procedure could be used as a tool to evaluate fish quality, verify fish sensitivity to a certain bacterial strain or evaluate the pathogenicity of a bacterium towards a given fish species. The availability of a challenge test is a prerequisite in studies dealing with the effect of different medicinal treatments on diseased fish. An oral challenge test would offer the possibility to investigate the routes of infection via the digestive tract, i.e. after feeding contaminated feeds. The present study aims to verify this hypothesis and proposes a standard challenge procedure for turbot (&lt;i&gt;Scophthalmus maximus&lt;/i&gt;) larvae with a pathogenic &lt;i&gt;Vibrio...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diseases; Digestive system; Disease control; Fish culture; Fish diseases; Fish larvae; Marine fish; Pathogenic bacteria; Vibrio anguillarum.
Ano: 1994
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2552

Live-food mediated drug delivery as a tool for disease treatment in larviculture: the enrichment of therapeutics in rotifers and &lt;i&gt;Artemia&lt;/i&gt; nauplii
Provedor de dados: 27
Autores: Verpraet, R.; Chair, M.; Léger, P.; Nelis, H.; Sorgeloos, P.; De Leenheer, A.P.
The live food enrichment technique using emulsions for nutritional deficiencies in rotifers and &lt;i&gt;Artemia&lt;/i&gt; was further investigated as a tool for transferring therapeutics through the food chain. &lt;i&gt;Artemia&lt;/i&gt; nauplii and the rotifer &lt;i&gt;Brachionus plicatilis&lt;/i&gt; were enriched with a self-emulsifying concentrate in which the therapeutic mixture trimetoprim: sulfamethoxazole was incorporated. An analytical method and protocol for the quantification of trimethoprim and sulfamethoxazole in a heterogeneous biological matrix, such as &lt;i&gt;Artemia&lt;/i&gt; , was developed using High Performance Liquid Chromatography. When applying a 24h enrichment period, the accumulation of both drugs in &lt;i&gt;Artemia&lt;/i&gt;...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquaculture systems; Disease control; Drugs; Food chains; Therapy; Artemia.
Ano: 1992
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2894

Liquid chromatographic determination of efficacy of incorporation of trimethoprim and sulfamethoxazole in brine shrimp (&lt;i&gt;Artemia&lt;/i&gt; spp.) used for prophylactic chemotherapy of fish
Provedor de dados: 27
Autores: Nelis, H.; Léger, P.; Sorgeloos, P.; De Leenheer, A.P.
The brine shrimp &lt;i&gt;Artemia&lt;/i&gt; , an excellent live food source in aquaculture, has been studied as a carrier to deliver selected chemotherapeutic agents to fish for prophylactic treatment of infectious diseases. To monitor the efficiency of incorporation of trimethoprim and sulfamethoxazole in &lt;i&gt;&lt;i&gt;Artemia&lt;/i&gt; franciscana&lt;/i&gt;, a sensitive and specific analytical method was developed. It is based on homogenization of &lt;i&gt;Artemia&lt;/i&gt; nauplii in methanol, extraction of lipids with hexane, solid-phase cleanup on C&lt;sub&gt;18&lt;/sub&gt; cartridges, and reversed-phase liquid chromatography with detection at 210 nm. The method is sensitive (detection limit, on the order of 3 µg/g with a sample quantity of 30 mg...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquaculture techniques; Fish culture; Infectious diseases; Medicine; Artemia.
Ano: 1991
URL: http://www.vliz.be/imisdocs/publications/262329.pdf

&lt;i&gt;Cis&lt;/i&gt;- and &lt;i&gt;trans&lt;/i&gt;-canthaxanthin levels in &lt;i&gt;Artemia&lt;/i&gt; cysts of different geographical origin
Provedor de dados: 27
Autores: Nelis, H.; Lavens, P.; Sorgeloos, P.; Van Steenberge, M.; De Leenheer, A.P.
The carotenoid composition of &lt;i&gt;Artemia&lt;/i&gt; cysts from 17 geographical strains was studied. All-&lt;i&gt;trans&lt;/i&gt;-canthaxanthins and &lt;i&gt;cis&lt;/i&gt;-canthaxanthins were quantitatively determined using a non-aqueous reversed phase chromatographic method. In dehydrated cysts, the average &lt;i&gt;cis&lt;/i&gt;- and &lt;i&gt;trans&lt;/i&gt;-canthaxanthin levels (+/- SD) were 152 +/- 52 and 134 +/- 42 µg/g, respectively (range 38-227 and 67-201µg/g). The corresponding concentrations in hydrated cysts were (&lt;i&gt;cis&lt;/i&gt;) 177 +/- 60 µg/g (range 47-271 µg/g) and (&lt;i&gt;trans&lt;/i&gt;) 112 +/- 35 µg/g (range 52-169 µg/g). The &lt;i&gt;cis/trans&lt;/i&gt; concentration ratios averaged 1.13 (range 0.57-1.47) and 1.60 (range...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Artemia.
Ano: 1987
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3196

The effect of supplemental ascorbic acid in enriched live food for &lt;i&gt;Clarias gariepinus&lt;/i&gt; larvae at startfeeding
Provedor de dados: 27
Autores: 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 (&lt;i&gt;Clarius gariepinus&lt;/i&gt;) larvae has been assessed in two 10-day culture trials. Three treatments received only &lt;i&gt;Artemia&lt;/i&gt; nauplii enriched with an experimental emulsion containing 0, 10 or 20% ascorbyl palmitate (AP) and yielding 530, 1200 and 1600 µg AA g&lt;sup&gt;-1&lt;/sup&gt; DW &lt;i&gt;Artemia&lt;/i&gt; , respectively; the other three treatments were fed the same &lt;i&gt;Artemia&lt;/i&gt; 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

Dietary ascorbic acid requirements during the hatchery production of turbot larvae
Provedor de dados: 27
Autores: 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 &lt;i&gt;Scophthalmus maximus&lt;/i&gt; 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&lt;sup&gt;-1&lt;/sup&gt;) 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
Ano: 1996
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3022

Simultaneous determination of a-tocopheryl acetate and tocopherols in aquatic organisms and fish feed
Provedor de dados: 27
Autores: Huo, J.-Z.; Nelis, H.; Lavens, P.; Sorgeloos, P.; De Leenheer, A.P.
In aquaculture, alpha-tocopheryl acetate (alpha-TA) is the main source of vitamin E used to fortify fish feed. Alpha-TA in fish is often determined indirectly, i.e. by alkaline hydrolysis, followed by quantitation of ‘total alpha-tocopherol’ (alpha-T) and substraction of the natively present alpha-T. The aim of this study was to develop an HPLC method for the simultaneous quantitative determination of alpha-TA and free tocopherols in aquatic organisms and fish feed. The assay consists of a simple extraction with methanol containing butylhydroxytoluene (BHT) as an antioxidant, followed by reversed-phase chromatography with consecutive UV and fluorescence detection of alpha-TA and tocopherols, respectively. The peak of the internal standard tocol in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vitamin E; Vitamins.
Ano: 1999
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=4020

Live food mediated drug delivery as a tool for disease treatment in larviculture: a case study with turbot &lt;i&gt;Scophthalmus maximus&lt;/i&gt;
Provedor de dados: 27
Autores: Chair, M.; Dehasque, M.; Sorgeloos, P.; Nelis, H.; De Leenheer, A.P.
With the advent of intensive culture practices, occurrences of mass mortality caused by bacterial infections are commonplace. High doses of antibiotics or antibacterials are used in aquaculture by adding them to the water. Problems of palatability and leaching occur when the chemotherapeutic agents are incorporated in feeds. To circumvent these problems &lt;i&gt;Artemia&lt;/i&gt; can be used as a carrier. In this study we assess the efficacy of cotrimoxazole in the oral treatment of turbot larvae challenged with a pathogenic strain of Vibrio anguillarum encapsulated in &lt;i&gt;Artemia&lt;/i&gt;.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Scophthalmus maximus (Linneaus; 1758).
Ano: 1995
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2536

Determination of vitamin E in aquatic organisms by high-performance liquid chromatography with fluorescence detection
Provedor de dados: 27
Autores: Huo, J.-Z.; Nelis, H.; Lavens, P.; Sorgeloos, P.; De Leenheer, A.P.
A liquid chromatographic (HPLC) method has been developed for the quantitative determination of different forms of vitamin E (alpha-, gamma-, and delta-tocopherol) in aquatic organisms. The assay consists of a simple extraction with methanol containing butylhydroxytoluene (BHT) as an antioxidant, followed by reversed phase chromatography with fluorescence detection. The efficiency of the extraction method was equivalent or superior to that of more complex approaches for the isolation of tocopherols. Linearity has been achieved over the range of 0.02 to 3 µg/ml for alpha-tocopherol and within-run and between-run coefficients of variation at three levels were 0.7-2.9 and 1.2-3.7%, respectively. The recovery at three concentrations ranged from 73.8 to 96.6%...
Tipo: Info:eu-repo/semantics/article
Ano: 1996
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2978

Influence of dietary vitamin C dosage on turbot (&lt;i&gt;Scophthalmus maximus&lt;/i&gt;) and European sea bass (&lt;i&gt;Dicentrarchus labrax&lt;/i&gt;) nursery stages
Provedor de dados: 27
Autores: 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, &lt;i&gt;Dicentrarchus labrax&lt;/i&gt;. 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 (&lt;i&gt;Scophthalmus maximus&lt;/i&gt;) 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

Improved production of postlarval white shrimp through supplementation of L-ascorbyl-2-polyphosphate in their diet
Provedor de dados: 27
Autores: 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 (&lt;i&gt;Penaeus vannamei&lt;/i&gt;). 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&lt;sup&gt;-1&lt;/sup&gt; expressed as active AA were fed &lt;i&gt;ad libitum&lt;/i&gt; to &lt;i&gt;P. vannamei&lt;/i&gt; (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

Live-food mediated drug delivery as a tool for disease treatment in larviculture: 2. A case study with European seabass
Provedor de dados: 27
Autores: Chair, M.; Romdhane, M.S.; Dehasque, M.; Nelis, H.; De Leenheer, A.P.; Sorgeloos, P.
The purpose of this study is to investigate the possibility of oral delivery of the antibiotics Trimethoprim (TMP) and Sulfamethoxazole (SMX) to marine fish larvae through incorporation of these antibiotics into the live food organism &lt;i&gt;Artemia&lt;/i&gt;. SMX and TMP were selected for their wide range action against gram negative pathogenic bacteria and because of their limited solubility in seawater. Ormetoprim-Sulfadimethoxine (brand name Romet-30) is a new combination of a similar antimicrobial drug used in aquaculture. Diseased penaeid larvae fed Romet-30 through the food chain exhibited greater survival than the untreated ones. In an earlier study Verpraet have described a technique for bioencapsulating high doses of more than 500 mu g TMP +...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antibiotics; Aquaculture techniques; Disease control; Fish culture; Fish larvae; Food additives; Food organisms; Dicentrarchus labrax [Bass].
Ano: 1991
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2805