Effect of the microalga isochrysis galbana on the early larval culture of paralichthys adspersus

Abstract

A first feeding experiment on Chilean flounder larvae (Paralichthys adspersus), using Isochrysis galbana in culture tanks and a rotifer enrichment technique, was performed with 4500 larvae in nine 25-L tanks with green and clear water, and fed rotifers enriched with DHA Selco and I. galbana. The results were evaluated in terms of survival, growth, development and larval viability (stress-test). Larvae in green water with rotifers enriched with DHA Selco (AV-R-DHA) and larvae in clear water with rotifers enriched with I. galbana (AC-R-IG) showed significant differences in survival, growth, development and viability, compared to larvae in clear water with rotifers enriched with DHA Selco (AC-R-DHA). Furthermore, there were no significant differences in survival, growth and development between larvae in AV-R-DHA and larvae in AC-R-IG, suggesting that I. galbana could improve and support satisfactory nutritional levels in rotifers to sustain development of flounder larvae. The high viability shown by larvae in green water and the high level of docosahexaenoic acid (DHA) content in I. galbana suggest a important role of DHA in the final quality of flounder larvae.