抄録
Two groups of 10- and 11-year-old striped jack Pseudocaranx dentex (Bloch et Schneider) of 4.8kg average weight were used to determine whether these fish were able to spawn normally after being fed with dry pellets. Four months prior to spawning, they were divided into a test group and a control group and fed a commercial soft-dry pellet (cSDP) and a raw fish mix (RF), respectively, three times per week, in floating cages. For the spawning manipulation, the fish were transferred to indoor spawning tanks where they were fed once a day, for six days a week.
The RF group spawned eggs on 37 days during a 66-day period, whilst the cSDP group spawned on only 27 days during a 40-day period, the former therefore producing about three times the amount of eggs produced by the cSDP group. The eggs from the RF and cSDP groups had buoyancy rates of 83.2% and 71.0%, and fertilization rates among buoyant eggs of 79.6% and 78.2%, respectively. The percentage of normal larvae obtained from the total eggs produced was also higher for the RF group, 60.3% compared to 45.9% of the cSDP group. Despite this, the egg diameters and survival activity index of larvae were identical in the two groups. These results show that broodstock striped jack can also be cultivated by feeding cSDP prior to spawning.
