Mussel and oyster culture in Denmark
Kristensen, P.S. (1989). Mussel and oyster culture in Denmark, in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 341-350
In: De Pauw, N. et al. (1989). Aquaculture: a biotechnology in progress: volume 1. European Aquaculture Society: Bredene. ISBN 90-71625-03-6. 1-592 pp., meer
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Beschikbaar in | Auteur |
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Documenttype: Congresbijdrage
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Abstract |
In Danish waters, experiments on growing mussels (Mytilus edulis) and oysters (Crassostrea gigas) in suspended culture have been carried out for the last 5-7years. Good larvae-and spat populations occur in all these waters. Imported oyster seed (2g) grew to over 50g within 18-30 months. The major problem in growing oysters was the fouling of cages with mussels and subsequent competition for food. Strips of nets were shown to be excellent for spat collection and ongrowing of mussels. In the Isefjord, the number of spat collected in June/July varied from 6000 to 36 000 seed.m-1 of growthline (160 mussels.cm-2). After 1 month, the number of seed declined to 3000-5000.m-1, due to intraspecific competition. Mussels in suspension grew to 5cm in shell length within 15 months. The wet weight ranged from 10 to 19g per individual. Per meter of growthline (net strips), 3kg of marketable mussels were harvested. The condition indices (CI) were better for farmed mussels (0.2-0.3), than for wild stock mussels (0.1 ). The meat content (steamed) of cultured mussels (25-30%) was higher than that of mussels from the natural stocks (8-14%). Mussels grown in suspension contained only half the pollutants (lead, mercury) compared to bottom-growing mussels. Cultured mussels were competitive with wild stock mussels on the wholesale market. Mussels grown on longlines could however, not compete in price with natural stocks as raw material for the canning industry .Longline growing systems could be seriously damaged by heavy winter ice cover. |
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