Growth model of the reared sea urchin Paracentrotus ... - SciViews

Annexes
EXECUTIVE SUMMARY: The aim of the research is to succeed in
continuously producing large amount of edible sea urchins with high
gonadal productivity under controlled conditions (aquaculture). The
selected species is Paracentrotus lividus (viz. the edible echinoid species
from Europe). The research focuses on the following aspects:
a. Investigation on metamorphic events, with a special interest in
the morphological changes affecting metamorphic larvae and in
the metamorphosis inducing factors (this approach needs to
perform routinely mass-cultivation of larvae);
b. Optimization of juveniles' somatic growth and adults' gonadal
productivity under rearing conditions;
c. Study of reproductive periodicities in field and cultivated
individuals (investigations on parameters responsible for the
cycling of reproduction and the duration of the spawning period)
and attempt for a continuous reproduction under aquaculture
conditions.
Spirlet, Ch., Ph. Grosjean & M. Jangoux, 1994. Differentiation of the
genital apparatus in a juvenile echinoid (Paracentrotus lividus). In: B.
David, A. Guille, J.-P. Féral & M. Roux (eds). Echinoderms through
Time, Balkema, Rotterdam. Pp. 881-886.
ABSTRACT: Gonad and genital pore development was observed on
field and cultivated juveniles of the echinoid Paracentrotus lividus. The
gonad condition was evaluated by counting the number of acini per gonad
following dissection. Presence of the genital pores was determined for
each individual, plate by plate, after partial digestion of the tissues.
Progressive and relative development was determined. The gonads first
appear as a filament which starts to bud and develop acini that eventually
fill up with genital material. The pores are pierced from the inside out
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