Effects of feeding differentially enriched Artemia nauplii on the survival, growth, fatty acid composition, and air exposure stress response of Pacific cod (Gadus macrocephalus) larvae

The ability of enriched live food, such as Artemia, to improve the growth performance of Pacific cod (Gadus macrocephalus) larvae during larviculture has yet to be fully established. Thus, the effects of feeding differentially enriched Artemia to Pacific cod larvae were investigated here, specifically the effects on the survival, growth, fatty acid composition, and air exposure stress response of the larvae. Three different commercial Artemia enrichment emulsion oils were used: commercially available enrichment 1, 2, and 3, referred to as ER1, ER2, and ER3, respectively. Although ER2-treated Artemia contained the most eicosapentaenoic acid (EPA) and ER3-treated Artemia contained the most docosahexaenoic acid (DHA) and highly unsaturated fatty acid (HUFA), the ER1 enrichment improved overall survival, growth, and survival after air stress test to the greatest extent in larval Pacific cod. Furthermore, the levels of DHA and HUFA observed in larvae fed the ER1 diet were higher than the respective concentrations of these nutrients observed in larvae fed the other diets. Thus, under the experimental conditions applied in the present study, ER1 provided Artemia with DHA and EPA ratio of 4.1 for early feeding of Pacific cod larvae.