THE ROLE OF CAROTENOIDS IN THE DEVELOPMENT OF THE SEA-URCHIN PSEUDOCENTROTUS-DEPRESSUS

The role of dietary beta, beta-carotene, beta-echinenone, astaxanthin, vitamin A and vitamin E in development of the sea urchin Pseudocentro tus depressus was investigated by feeding experiments. The number of o vulated eggs was 16.3+/-3.1, 27.5+/-12.8, 35.7+/-12.0, 15.1+/-4.5, 15. 9+/-10.7 and 46.8+/-15.0 eggs/female (x10(-4)) in control, beta, beta- carotene, beta-echinenone, astaxanthin, vitamin A and vitamin E groups , respectively. Both beta-echinenone and vitamin E diets had statistic ally significant effects on ovulated eggs. Though the rate of fertiliz ation was nearly 100% in all test groups except the vitamin A group, t he hatching rate was 66.3, 71.6, 50.8, 37.0, 24.0 and 51.8% in control , beta, beta-carotene, beta-echinenone, astaxanthin, vitamin A and vit amin E group, respectively. The lowest malformation rates were obtaine d for beta, beta-carotene and beta-echinenone groups. In the case of t he control group, the malformation rate was 72% of the total plutei, a nd the survival rate was only 4.0% from fertilized egg to the 6-armed stage, and that of beta, beta-carotene, beta-echinenone, astaxanthin, vitamin A and vitamin E groups was 14.9, 13.6, 6.0, 6.3 and 8.6%, resp ectively. beta, beta-carotene and beta-echinenone had significant effe cts on larval survival. However, the vitamin E diet, which affected th e number of ovulated eggs, had no significant effects on larval surviv al. From the results of the developmental experiments described above, the beta-echinenone group represented the best achievement of all the test groups in both number of ovulated eggs and survival rate. Vitami n A had no effect on either of them. Although a mechanism for these ef fects cannot yet be identified, the results of this experiment would i ndicate that carotenoids, especially beta-echinenone, exert a major in fluence on early development.