Influence de la qualité de la lumière en élevage intensif de Palaemon serratus Pennant = Influence of light characteristics in intensive culturing of Palaemon serratus Pennant
Van Wormhoudt, A.; Ceccaldi, H.J. (1976). Influence de la qualité de la lumière en élevage intensif de Palaemon serratus Pennant = Influence of light characteristics in intensive culturing of Palaemon serratus Pennant, in: Persoone, G. et al. (Ed.) Proceedings of the 10th European Symposium on Marine Biology, Ostend, Belgium, Sept. 17-23, 1975: 1. Research in mariculture at laboratory- and pilot scale. pp. 505-521
In: Persoone, G.; Jaspers, E. (Ed.) (1976). Proceedings of the 10th European Symposium on Marine Biology, Ostend, Belgium, Sept. 17-23, 1975: 1. Research in mariculture at laboratory- and pilot scale. IZWO: Wetteren. ISBN 90-6281-001-2. 620 pp., meer
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Documenttype: Congresbijdrage
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| Auteurs | | Top |
- Van Wormhoudt, A.
- Ceccaldi, H.J.
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| Abstract |
At 15 °C, a 16 hr photophase permits a good growth rate of the shrimp Palaemon serratus, whereas a 10 hr photophase slows it down. Blue and green lights stimulate the growth; red and orange ones inhibit it. The digestive enzymatic activities of Palaemon serratus vary in cycles characterized by two maxima during the day, with a 12 hr period. The amplitude of the enzymatic variations is maximal for a photoperiod close to the natural one; eyestalkless animals also show variations in connection with modifications in the experimental photoperiod. The internal rhythm of these crustaceans seems to correspond to a 12-12 cycle. Circadian variations of digestive enzymatic activities show less variations when animals are maintained in darkness. They reappear after a short and weak exposure to light. Animals maintained in darkness during a long period have a digestive enzymatic response proportional to the quantity of light received, when they are exposed to short light stimulation. Wavelengths stimulating the digestive enzymatic activities most intensively are very close to 360 nm and 540 nm. At 620 nm the stimulus is much weaker. In green light, short, high energy light, has the same effect as a exposure during a longer period with a light of less energy. Significant responses were obtained with total energy doses higher than 2.200 fµW/ cm². The digestive enzymatic activities induced by these short light exposures are different according to the stage of the moulting cycle and the hour at which they are applied. This phenomenon is most presumably connected with different neurosecretory conditions. The induced digestive enzymatic activities are also linked to seasonal variations. |
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