Food Consumption, Absorption, Assimilation and Growth of the Sea Urchin Strongylocentrotus intermedius Fed a Prepared Feed and the Alga Laminaria japonica

Abstract

Prepared feeds are standard for developed aquaculture programs. Prepared feeds have been shown to be effective for several species of sea urchins. We investigated the use of prepared feeds for culture of the important commercial species Strongylocentrotus intermedius by comparison with the usual food used, the brown alga Laminaria japonica. The experiment was done in the summer and consisted of two successive 30-d periods. Individuals consumed more of the alga than the prepared feed but the absorption efficiencies were the same. This probably resulted from a higher content of structural carbohydrates in the alga and a higher content of available organic matter in the feed. The amount of organic matter absorbed was the same for both foods. However, the amount of gonad production and the assimilation efficiency was greater for the prepared feed. This indicates the prepared feed is of better nutritional quality. The physiological measurements and production were greater in the first 30-d period when the temperature was 21 C. This indicates temperature will be an important consideration in aquaculture of S. intermedius.