Complete larval development of the sea urchin Lytechinus variegatus fed an artificial feed

Complete development of sea-urchin larvae fed an artificial feed has been carried out for the first time. Naturally spawned gametes were obtained from adult Lytechinus variegatus fed an artificial feed in the laboratory for 9 months. Larvae from these adults. cultured in artificial seawater and fed microencapsulated capsules, reached the rudiment stage between 9 and 12 days. the usual time required. Larvae produced by artificial spawning and cultured in natural seawater and fed microencapsulated capsules or phytoplankton (Dunaliella tertiolecta) had similar chronology of development and sizes of newly metamorphosed juveniles. The larvae fed capsules were significantly smaller than those fed D. tertiolecta. Larval survival was 72+/-6% for those fed capsules and 85+/-4% for those fed D. tertiolecta. Artificial feed for larvae eliminates the necessity of culturing phytoplankton and provides the potential of establishing nutritional requirements of lanae and of standardizing and manipulating the diet. This has application in mass aquaculture of sea urchins as well as using larvae as models in developmental studies. (C) 2004 Elsevier B.V. All rights reserved.