Rearing larval stages of fish on dry diets: the example of Coregonus lavaretus
Segner, H.; Rösch, R. (1992). Rearing larval stages of fish on dry diets: the example of Coregonus lavaretus, in: Progress in aquaculture research: proceedings of the 4th German-Isreali Status Seminar held on October 30-31, 1990. Spec. Publ. Eur. Aquacult. Soc, 17: pp. 279-296 In: Moav, B.; Hilge, V.; Rosenthal, H. (Ed.) (1992). Progress in aquaculture research: Proceedings of the 4th Status Seminar held on October 30-31, 1990 in GKSS-Forschungszentrum Geesthacht GmbH. Spec. Publ. Eur. Aquacult. Soc, 17. European Aquaculture Society: Oostende. ISBN 90-71625-11-7. 360 pp., more In: Spec. Publ. Eur. Aquacult. Soc., more |
| Abstract | Fish reared from larval stage on dry diets, often attain lower growth rates than those fed on live food. Using studies on larval Coregonus lavaretus as an example, three major factors contributing to reduced growth performance are discussed. 1) Food acceptance: A delayed start of dry food intake by larval Coregonus lavaretus results in a late induction of growth processes. After start of food ingestion, low consumption of dry diets reduces growth rates. 2) Food digestion: Problems encountered in rearing the larvae on formulated diets do not seem to be the result of a general lack in digestive capacity during early life, since, with the exception of the stomach, the digestive system of Coregonus lavaretus is well developed at the beginning of exogenous feeding. The larvae modify digestive functions in response to ingestion of dry diets. Despite such alterations, digestibility of compound feeds is obviously lower than that of live food. 3) Food quality and metabolism: Dry starter diets fulfill basic nutritional requirements of the larvae. However, the diets do not stimulate larval metabolic activities in general, and protein synthesis in particular, to the same degree as do live feeds. |
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