A histo-morphometric approach of the reproductive cycle of the gudgeon, Gobio gobio L. Effects of temperature and photoperiod (Abstract)
Kestemont, P. (1989). A histo-morphometric approach of the reproductive cycle of the gudgeon, Gobio gobio L. Effects of temperature and photoperiod (Abstract), in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 537
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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| Abstract |
The reproductive cycle of a European baitfish, the gudgeon, Gobio gobio L. was studied by a histo-morphometric approach, given stereological corrections based on the Wicksell's transformation. Arbitrarily four stages of maturity (one protoplasmic stage and three vitellogenic stages) were determined in order to quantify the ovogenetic process. These histological criterions are related to the macroscopic characteristics of maturity (gonadosomatic index and condition coefficients, K and K1). In a second step; the effects of the two proximate factors, temperature and photoperiod on the gametogenesis of the gudgeon were investigated. The gonadal development, modulated by different combination of temperature and photoperiod, was compared to the annual reproductive cycle of the gudgeon reared in ponds. The relative importance of these two factors is clearly related to the gametogenetic stage (recrudescence stage or final maturation stage) Under constant conditions of temperature and photoperiod, a strong regression of the vitellogenic oocytes was observed; a period of low temperature or decreasing photoperiod seems necessary to allow the gonadal recrudescence. An annual cycle condensed to 6 months accelerates the gametogenesis and produces off-season spawnings. Nevertheless, final maturation and ovulation are mainly dependent on temperature. |
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