Effect of squid meal in dry
pellets on the spawning performance of striped jack Pseudocaranx dentex
R. Vassallo-Agius, H. Imaizumi, T. Watanabe, T.
Yamazaki, S. Satoh, V. Kiron-2001
Fisheries Science, 67 (2) : 271-280
(from Current Contents)
Abstract :
This study was carried out to investigate the effects
of dietary squid meal or a combination of squid meal and krill meal as
part of the protein source in dry pellets on the spawning of striped jack
Pseudocaranx dentex. Five months prior to spawning, 7-year-old fish were
divided into three groups of 10 fish each (male:female ratio, 5:5). The
control group was fed a raw fish mix (RF) and the other two groups were
fed either steam-dry pellets with squid meal replacing 50% of their fish
meal (fs-DP) or steam-dry pellets containing equal proportions of fish,
squid and krill meals (fsk-DP). Feeding was carried out once every other
day in 5x5x5 m floating net cages and the fish were transferred to 65 m(3)
indoor tanks for spawning. Eggs and yolksac larvae produced were evaluated
for their quality and those obtained during the first 2 weeks of spawning
were sampled for chemical analysis. The fish had an average bodyweight of
3.5+/-0.4 kg at spawning. Although egg production of the RF group was
significantly higher (P<0.05) than that of the dry pellet groups, the
fs-DP group produced the best quality eggs with higher fertilization and
hatching rates. The fsk-DP group had the lowest egg production and
quality. Lipid classes and fatty acid compositions of eggs and yolksac
larvae were dependent on the broodstock diets. These results show that the
combination of fish meal and squid meal in dry pellets for striped jack
improved egg quality but not production whereas the combination of fish
meal, squid meal and krill meal was not effective.