The concomitant replacement of fish meal and fish oil in carnivorous marine fish feeds by more sustainable terrestrial alternatives is problematic due to the limited capability of marine fish to synthesize physiological essential long chain n-3 and n-6 highly unsaturated fatty acids (HUFAs) from shorter chain fatty acid precursors present in some vegetable oils. This two-year study will employ sablefish (Anoplopoma fimbria) as a model marine finfish to systematically investigate the potential of fully replacing the added fish oil component of a typical low fishmeal feed suitable for marine aquaculture.

The focus of the proposed study will be on the effects of replacing fish oil in sablefish diets with sustainable lipid sources on diet utilization and growth. In particular, the overall goals of the proposed research are the following:

1. Determine the ability of sablefish to synthesize essential HUFAs from shorter chain fatty acid precursors.

2. Explore the effects of supplementing alternative vegetable oil feeds with novel sources of essential fatty acids on growth and nutrient utilization.

3. Evaluate the feasibility of using these novel oils in practical feeds. Data obtained in these studies will further our understanding of sablefish nutrition and set the stage for future research on the effects of sustainable feed ingredients on product quality, fish health, and the reproductive potential of cultured broodstock programs. This research specifically addresses a priority of the 2008 National Marine Aquaculture Initiative, which is nutrition research involving alternative protein based diets and the influence of diet on product quality. Whole fish proximate composition.