Improvements in the larviculture of turbot Scophthalmus maximus: zootechnical and nutritional aspects, possibility for disease control
Dhert, Ph.; Lavens, P.; Dehasque, M.; Sorgeloos, P. (1995). Improvements in the larviculture of turbot Scophthalmus maximus: zootechnical and nutritional aspects, possibility for disease control, in: Lavens, P. et al. Larvi '95: Fish & Shellfish Symposium, Gent, Belgium, September 3-7, 1995. EAS Special Publication, 24: pp. 32-46
In: Lavens, P.; Jaspers, E.; Roelants, I. (Ed.) (1995). Larvi '95: Fish & Shellfish Symposium, Gent, Belgium, September 3-7, 1995. Special Publication European Aquaculture Society, 24. European Aquaculture Society: Gent. ISBN 90-71625-14-1. XXVI, 521 pp., more
In: Special Publication European Aquaculture Society. European Aquaculture Society: Bredene. ISSN 0774-0689, more
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Document type: Conference paper
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Keywords |
Scophthalmus maximus (Linnaeus, 1758) [WoRMS] Marine/Coastal |
Abstract |
The rotifer feeding regime for larval turbot could be improved by more regular feeding and adjusted food distributions as to prevent overfeeding and digestion problems. All tests were successfully run in clear-water conditions indicating that the administration of algae is not essential during the rotifer stage. Larval requirements with respect to (n-3) RUFA, and more specifically DRA and DRA/EPA ratio appeared to change according to the age of the larvae and the physiological condition at the different larval stages. As early as the first week the stress resistance of the larvae could be improved by feeding rotifers specifically enriched in DRA. However, the continuous feeding of these live preys did not result in the best larval output, indicating that satiation levels for DRA were exceeded. Light had an effect on the survival of the larvae and affected indirectly their stress sensitivity and colour. Again, the incorporation of high levels of the essential fatty acid DRA in the live diet significantly reduced stress and allowed normal coloration of the larvae before metamorphosis. Final pigmentation was also positively enhanced by the incorporation of DRA into the diet. Disease treatment/prevention in the young larval stages of turbot was accomplished through oral administration of drugs via incorporation into the live food Artemia. Turbot larvae, experimentally infected with a virulent strain of Vibrio anguillarum, showed a significantly higher survival after treatment with medicated Artemia compared to the untreated control. |
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