Effects of dry pellets containing astaxanthin and squid meal on the spawning performance of striped jack Pseudocaranx dentex
R. Vassallo-Agius, T. Watanabe, H. Imaizumi, T.
Yamazaki, S. Satoh, V. Kiron-2001
Fisheries Science, 67(4): 667-674
(from Current Contents)
Abstract:
This study was conducted to investigate the effect of
squid meal and astaxanthin in dry pellets on the spawning performance of
striped jack. Two groups of 8-year-old fish with an average bodyweight of
3.5 +/- 0.4 kg were used. The control group was fed a raw fish mix (RF) and
the experimental group was fed steam dry pellets (as-DP) containing 10
p.p.m. astaxanthin and squid meal, the latter replacing half the fish meal.
Each group was fed once a day, three times a week in floating net cages for
a period of 5 months. Seven females and seven males were selected from each
group and transferred to 65 m(3) indoor concrete tanks for spawning, where
they were kept at optimum spawning conditions (22°C) for 1 month. The
average bodyweights of selected fish were 3.8 +/- 0.5 kg and 3.8 +/- 0.6 kg
for the RF and as-DP groups, respectively. Both groups spawned a total of 18
times and the mean total egg production and egg quality, measured in terms
of buoyancy, fertilization and hatching rates, showed no significant
differences (P>0.05) between groups. Total larval production was 679.9 x
10(3) and 678.1 x 10(3) larvae/kg-female for the RF and as-DP groups,
respectively. These results show that the combination of astaxanthin and
squid meal in dry pellets for striped jack broodstock improved the overall
spawning performance to a level similar to that of fish fed on RF.
(Tokyo Univ Fisheries, Dept Aquat Biosci, Tokyo
1088477, Japan, e-mail of T. Watanabe: watana@tokyo-u-fish.ac.jp)