EFFECT OF FOOD CONCENTRATION ON PROTEIN AND CARBOHYDRATE PRODUCTION DURING LARVAL DEVELOPMENT OF THE SEA URCHIN LYTECHINUS VARIEGATUS

Abstract

Abstract Changes in protein and carbohydrate content during larval development of Lytechinus variegatus were measured under two diet conditions, low concentration (600 algal cells ml−1 day−1) and high concentration (6,000 algal cells ml−1 day−1) to determine the larval stage at which these proximate constituents showed significant changes under different conditions of food availability. In terms of morphology, larvae under the high concentration diet developed fully and metamorphosed after 30 days, whereas under the low concentration diet, some larvae developed up to the 4 arm stage, and some ceased to develop at the 8 arm stage. No significant differences were found in the percentage of larval survival up to day 24 with both treatments (high: 77 ± 18%, low: 66 ± 24%). With the high concentration diet, protein and carbohydrate content per larvae remained relatively constant through day 17 after fertilization, through the 8-arm stage, and then significantly increased by day 20 coinciding with the first app...