INFLUENCE OF COMPOSITION OF BRACHIONUS-PLICATILIS AND ARTEMIA ON GROWTH OF LARVAL SABLEFISH (ANOPLOPOMA-FIMBRIA PALLAS)

Larval sablefish, Anoplopoma fimbria, were fed rotifers, Brachionus pl icatilis, and later brine shrimp, Artemia, reared on the microalgae, N annochloropsis oculata, Isochrysis galbana (T-Iso) and Chroomonas sali na. Diet composition significantly influenced growth and time to 50% m ortality of larvae. Survival was greatest for the group fed zooplankto n reared on N. oculata and least in the group reared on C salina. Prot ein content was significantly higher in rotifers reared on L galbana ( T-Iso) than on the other algae, but was not correlated with larval gro wth or survival. Lipid content of rotifers was independent of algal sp ecies used in production. Carbohydrate was highest in rotifers fed N. oculata and may have influenced the survival of sablefish larvae. Cont ents of protein, lipids and carbohydrate in Artemia reared on differen t algae were not significantly different, minimizing any influence on growth and development of the larvae. Contents of constituent fatty ac ids in rotifers, but not Artemia, were the major differences in these dietary plankton fed to fish larvae. B. plicatilis contained 15% 20:5n -3 (EPA) and 0.3% 22:6n-3 (DHA) when reared on N. oculata, 3.3% EPA an d 5.2% DHA when reared on L galbana (T-Iso) and 5.6% EPA and 3.0% DHA when reared on C salina. The failure to rear the larvae beyond day 60 from first feeding and the observed 50% n-3 HUFA in lipid of sablefish eggs and pelagic zooplankton, suggests that the dietary HUFA levels u sed to feed larvae in this study were too low to meet the apparent HUF A requirement.