The number of larvae from re-brooded coonstripe shrimp Pandalus hypsinotus
2006
Watanabe, T.(Toyama-ken. Fisheries Research Inst., Namekawa (Japan)) | Yoshida, K.
In Toyama Prefecture, the seedling production of the Coonstripe shrimp, Pandalus hypsinotus, was started in 1996, using ovigerous females to obtain larvae for the seedling production. However the annual catches have not been consistent. The present work was undertaken to determine the number of larvae re-brooded Coonstripe shrimps produce as a result of successive spawning in captivity. In March-April, 2002, a total of 60 females was divided equally into two groups, depending on the differences in the food supply after seedling production. Each group of 30 females was kept in a tank (1 cubic m) together with 15 wild males. The first group was fed with raw bait and the second group with a processed commercial diet. In May-August, 2003, 14 individuals underwent second brooding, eight in the first group and six in the second group. Thereafter, each brooded female was kept individually and fed with raw bait in a small aquarium (20 x 35 x 25cm). The larvae started to hatch from January, 2004, and continued until the end of May, 2004. The shrimps in the first group produced a statistically larger number of larvae than those in the second group. These results suggest that re-brooded Coonstripe shrimps have a high potential for successive use in seedling production.
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