Larvae of Ostrea edulis (L.) during starvation: Growth, energy and biochemical substrates

Abstract

The aim of the present study is to explain the differing utilisation of the various biochemical substrates in energy terms during the larval development of O.edulis, associating this with the evolution of the culture as regards survival and growth in conditions of total starvation. The larvae of O.edulis immediately after their release from the paleal cavity of the parent oyster have significantly higher reserves of proteins than of lipids and carbohydrates, and that in conditions of total starvation, the utilisation of proteins and lipids are similar and significantly greater than that of carbohydrates. In the case of lipids, energetic lipids decrease in greater amounts than structural lipids. Seen in this light, the viability of a larval culture should not be simply attributed to the accumulation of sufficient reserves of a simple substrate in order to meet the energy demands of the larvae. Instead, survival may well depend on the ability to mobilise various types of substrate in order to meet different anabolic and catabolic needs, amongst which are those relating to shell formation. In this work, an energetic expenditure of 17.86 1.12 KJ has been estimated to deposit 1 g of shell, which corroborates the great importance that shell formation has in larval development processes, where the role of proteins may be interpreted in the context of this physiological process.