Essential fatty acid nutrition of larval striped bass morone saxatilis and palmetto bass morone saxatilis x morone chrysops
Tuncer, H.; Harrell, R.M.
Aquaculture 101(1-2): 105-121
Essential fatty acid (EFA) requirements of striped bass and palmetto bass ( striped bass .times. white bass) larvae were investigated using three Artemia nauplii diets: (1) a control diet (Great Salt Lake strain), and same strain enriched with (2) corn oil, and (3) highly unsaturated n-3 fatty acids (HUFA - 20:3 < n-3 fatty acids). The n-6/n-3 ratio increased (6 fold) while the HUFA content of fish decreased (10 to 30 fold) in all treatments by age. At 28-d posthatch, palmetto bass showed no size differences among treatments, although striped bass fed the HUFA diet were significantly larger than those fed the other two diets. At methamorphosis from larvae to juveniles (26-28 d posthatch), both genetic groups fed the control and corn oil diets displayed EFA deficiency syndrome and mass mortality (85-99%), while larvae fed the HUFA diet had excellent survival (80%). Palmetto bass were more sensitive to EFA deficiencies than striped bass in the control and corn oil diets, as mortality was greater. Regression analyses revealed that the HUFA content, and not the other fatty acid families of diet and larvae, was responsible for the variation in growth and survival; the higher the HUFA content, the better the survival and growth. Both genetic groups emulated marine species with respect to their EFA requirements, and dietary HUFA was required at levels of 5.7 mg g-1 dry-wt Artemia nauplii.