The influence of astaxanthin supplemented dry pellets on spawning of striped jack [Pseudocaranx dentex]

This experiment was conducted to investigate the effect of astaxanthin supplemented steam-dry pellets on the spawning of striped jack Pseudocaranx dentex. Five months before spawning, 7-year-old fish were divided into three groups, each consisting of five females and five males. The control group was fed a raw fish mix (RF) and the test diets consisted of steam-dry pellets (DP) and steam-dry pellets supplemented with 10 p.p.m. astaxanthin (a-DP). Feeding was carried out once per day, three times a week in floating net cages. The RF and the a-DP groups produced more than three times the amount of eggs produced by the DP group. The buoyancy, fertilization, and hatching rates were higher and similar for the RF and the DP groups. Total lipid contents of the diets, eggs, and larvae were similar among the groups. Highly unsaturated fatty acids (n-3 HUFA) and polar and non-polar lipids in eggs and larvae were also related to their dietary availability. These results indicate that astaxanthin, due to its various physiological functions, improved the condition of the broodstock and enhanced total egg production but not egg quality as striped jack do not incorporate carotenoids into their eggs. Therefore we confirm that the nutritional quality of diets given to striped jack prior to spawning plays a fundamental role in egg production, quality and egg composition.