Rearing of the European catfish (Silurus glanis L.) to marketable size in warm water at the laboratory scale
Hilge, V. (1989). Rearing of the European catfish (Silurus glanis L.) to marketable size in warm water at the laboratory scale, in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 163-167
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., more
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Document type: Conference paper
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| Abstract |
Besides the main fishes in central European pond fish-culture trout and carp, there are several secondary species of considerable interest such as tench, pike or the European catfish. The latter is a very valuable species and offers some interesting aspects as for its intensive culture up to market size (1-2kg) or during younger stages only. A combination of both intensive-and pond-culture methods can be of advantage as well. The supply with catfish fry throughout the year is possible by maintaining a broodstock continuously in warm water. Female fish are regularly checked for maturity by ovarian catherization. Ripe specimens are induced to ovulate by injections of a crude extract of carp pituitary gonadotropin or gonadotropin-releasing hormone and dopamine inhibitor. First feeding of catfish fry relies upon live food, e.g Artemia nauplii. No artifical feed tests till now gave satisfactory results. At the age of 2-3 weeks fry has a body weight of 0.3-0.49 and can easily be weaned on a formulated diet. At optimal water temperatures for growth of 25-27°C Silurus can reach a weight of 20g (15cm) within 4 months from hatch in 1.5m³ plastic tanks under such conditions 1 kg body weight is attainable at 1 yr of age. Levels of trace contaminants in catfish raised under intensive culture conditions were far below the limits of acceptability for human consumption. The proximate analysis revealed a protein content of 19% in the fillet while fat was generally 2%. In an organoleplic test the European catfish as compared directly to an African (Clarias gariepinus) and an American (Ictalurus punctatus) species, with three modes of preparation (smoked, fried, and cooked), clearfy obtained the highest esteem. These facts offer some interesting prospects for the culture of this species from both the producers' and the consumers' point of view. |
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