Participating organizations (WP leader in bold): P1. HCMR, P2. FCPCT, P8. IEO, P15. ULL, P20. SARC and P28. CANEXMAR
Task 9.1 Improve larval enrichment products to enhance production of larvae and juveniles.
Task 9.2 Development of diets for grow-out of amberjack to maximize growth.
Task 9.3 Design adequate feeding regimes for broodstock to optimize reproduction. To overcome the unreliable reproduction of greater amberjack by addition of specific nutrients that have been shown to be important for gonad maturation and fecundity, several trials will be conducted:
Task 9.1 Improve larval enrichment products to enhance production of larvae and juveniles.
- Sub-task 9.1.1 The optimum essential fatty acid will be determined in enrichment products for live preys. Greater amberjack larvae will be fed live preys enriched with different levels of essential fatty acids and ratios prepared by FCPCT in order to determine the requirements for these nutrients during early larval development.
- Sub-task 9.1.2 Combined effect of PUFA-rich lipids and carotenoids will be evaluated. Triplicate trials will be carry out with amberjack larvae fed live preys enriched using three different levels of PUFA-rich lipids combined with two carotenoids levels.
Task 9.2 Development of diets for grow-out of amberjack to maximize growth.
- Sub-task 9.2.1 Lysine requirements will be determined in small amberjack. Diets based mainly on plant ingredients will be formulated and produced containing six levels of lysine in order to determine the optimum concentration in favor of health and welfare status of fish.
- Sub-task 9.2.2 The grow-out diet developed with the above information will be tested at an SME level, in order to assay its efficiency to maximize growth potential and enhance fillet quality. Survival, growth feed utilization and fillet quality will be determined.
Task 9.3 Design adequate feeding regimes for broodstock to optimize reproduction. To overcome the unreliable reproduction of greater amberjack by addition of specific nutrients that have been shown to be important for gonad maturation and fecundity, several trials will be conducted:
- Sub-task 9.3.1 The optimum ARA, EPA and DHA levels as essential fatty acids for reproductive success of greater amberjack will be studied. This Task will be complementary to Task 3.3 in WP 3 Reproduction and Genetics –Greater amberjack.
- Sub-task 9.3.2 Previous studies showed relevant differences in the lipid profile and fatty acid content of muscle, liver and ovary between wild and born in captivity Greater-amberjack broodstock. With the aim of approach the lipid and carotenoid egg profile of cultured females to their wild counterparts, experimental diets with optimized EFA and carotenoid contents will be tested in groups of amberjack broodstock. This Task will be complementary to Task 3.4 in the WP 3 Reproduction and Genetics – greater amberjack, in order to optimized spawning protocols for greater amberjack.