Ž . Aquaculture 166 1998 37–47 A biochemical study of the larval and postlarval stages of the Chilean scallop Argopecten purpuratus A. Farıas, I. Uriarte 1 , J.C. Castilla ´ Estacion Costera de InÕestigaciones Marinas, P. UniÕersidad Catolica de Chile, Las Cruces, Chile ´ ´ Accepted 16 December 1997 Abstract Eggs, larvae and postlarvae of northern scallop, Argopecten purpuratus, were collected from Ž . the experimental hatchery of the Estacion Costera de Investigaciones Marinas ECIM of the ´ Pontificia Universidad Catolica de Chile at Las Cruces to compare their protein, lipid and ´ carbohydrate composition. In the egg protein, lipid and carbohydrate accounted for 38.2, 34.1 and Ž . 1.5% ash-free dry weight AFDW , respectively. Protein in the larvae increased from 43.9 to 55.9% AFDW throughout larval development, and after metamorphosis values varied between 39.8 and 62.1% AFDW, with highest values in 22 day-old postlarvae. Lipids were constant at 20% AFDW during larval development, decreasing to 7.4% AFDW in the premetamorphosis period and increasing again to a constant value of 15% AFDW during the 22 days after metamorphosis, then decreasing to 2.5% AFDW. Carbohydrate contents were lower than lipid and protein in all larval stages, varying between 5.1 and 16.5% AFDW; during the postmetamorphosis period, carbohydrate content varied between 6.6 and 14.4%, but they were higher than lipid by day 60 after metamorphosis. The premetamorphosis period was characterized by a considerable decrease in lipid accompanied by a small decrease in protein and carbohydrate. The planting-out stage Ž . commercial seed was characterized by a high content of protein and a reduced content of lipid in relation to carbohydrate. This work provides basic information on the role played by the balance of energy reserves in the metabolism of scallop larvae. q 1998 Elsevier Science B.V. All rights reserved. Keywords: Argopecten purpuratus; Scallop hatchery; Energy reserves; Biochemical composition 1 Facultad de Oceanografıa y Pesquerıas, Universidad Austral de Chile. P.O. Box 1327, Puerto Montt, ´ ´ Chile. Fax: q56-65-255-583; e-mail: iuriarte@uach.cl. 0044-8486r98r$19.00 q 1998 Elsevier Science B.V. All rights reserved. Ž . PII S0044-8486 98 00204-X