The effects of density and temperature on the survival, growth, and colouration of the common goldfish, Carassius auratus (Abstract)
Kalicki, J.H.; King, D.P.F. (1989). The effects of density and temperature on the survival, growth, and colouration of the common goldfish, Carassius auratus (Abstract), in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 895
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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Documenttype: Congresbijdrage
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| Auteurs | | Top |
- Kalicki, J.H.
- King, D.P.F.
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| Abstract |
Common goldfish (Carassius auratus) were raised in two experimental environments, during the spring-summer to investigate how temperature affects survival, growth, and the colouration process under low (25 fry.m-2), medium (50 fry.m-2, and high (100 and 150 fry.m-2 stocking densities. The higher temperature environment (70-40°C) stimulated the occurrence of green algae (chlorophytes), especially of the genus Ankistrodesmus. In the lower temperatures (2-29°C) diatoms of the genus Syndera predominated. Growth and survival rates were lower as a result of low temperatures under all stocking densities. Moreover, fish produced at the low temperatures showed a high degree of mottling and displayed anaemic colouration. By contrast, fish raised in the higher temperature environment produced a good yield (~52%) of high quality well toned gold phenotypes. A noteworthy feature of fish raised at higher temperatures was the presence of highly irridescent scales on ~18% of these fish. This may be indicative of the partial suppression, at high temperatures, of the gene responsible for the regulation of guanine synthesis. In the higher temperature environment, neither survival, colouration or condition factor were affected by stocking density. Length and weight increases were significantly higher at stocking densities of 25 and 50.m-2 than at 100 and 150.m-2. |
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