Diet of the land vegetable Lactuca sativa as an alternative to macroalgae for the growth of juvenile the sea urchin Loxechinus albus in northern Chile

The sea urchin Loxechinus albus is of great commercial value due to its nutritional content. The main diet of the urchin in the north of Chile in its natural habitat is the macroalgae Ulva lactuca. This work evaluated the growth of L. albus juvenile fed diets based on vegetable lettuce Lactuca sativa and macroalgae Ulva sp. Ingestion, growth, survival, and proximal analysis of the diets were registered for 13 weeks. At the end of the experience (90 days), no mortality and greater consumption of L. sativa were observed. In the proximal analysis, L. sativa presented the highest percentage (lipids, proteins, ashes, carotenoids, chlorophyll). The greatest growth and weight gain were observed with the Ulva sp. diet. Finally, the incorporation of L. sativa in the diets of urchins would imply a supplement of minerals and carotenoids, so we propose the addition of this lettuce as a nutritional supplement during the first stage of the cultivation of the L. albus.