We completed the technique to constantly produce the artificial seeds of the short neck clam Ruditapes
philippinarum in large scale, because its natural resources have seriously been decreased in Japan. In Yanaguchi
Prefecture 10
7 seeds of 1-2mm in shell size have been able to obtain in a 100 m
3 tank from 1992, and about 2 × 10
7 seeds were produced annually. For incresing the survival rate of the released seeds, the intermediate culture of them unti1 10mm in shell size was carried out mainly by Yamaguchi Prefectural Fisheries Station and ten Fisheries Cooperative Associations. The large scale seed production of this clam and its intermediate culture are described in detail.
We, furthermore, present the results on the production of the seeds bearing a special color pattem on the
shell as a marker of the released seeds. Bp (banded purple) type shell, Which is very rare in the fields, could be
fixed genetically by the group and individual inbreedings. In 1996 we obtained the fourth generation of the Bp
type shell at the rate of 92.5 % in the group inbreeding experiments and nearly 100 % in the individual inbreeding
experiments. A pert of them were released to the fields after the intermediate culure.
抄録全体を表示