Potential for hatchery broodstock conditioning of the Caribbean scallops Argopecten nucleus and Nodipecten nodosus

Abstract

Argopecten nucleus and Nodipecten nodosus are two commercially valuable scallop species found in the western Caribbean region. Field and laboratory experimentation was carried out to determine the feasibility of artificial induction of gonadal development in these species in order to have fully mature broodstock to provide gametes for massive culture trials. Scallops were either maintained as a control in the sea, or conditioned in the laboratory, 1) fed intensively with Isochrysis galbana and, 2) Fed with I. galbana (70%) and a lipid emulsion containing docosahexaenoic acid (EmDHA; 30%). Scallops with empty gonads were employed; these scallops were visually monitored periodically to determine percentage of specimens in each stage of sexual maturity. Complete gonadal development was obtained in all of the A. nucleus maintained in the laboratory after 16 days when fed at the highest concentrations of food having the highest organic content. In contrast, only 40% of N. nodosus individuals in the sea, and 20% of those in the laboratory fed with I. galbana became fully mature after 77 days. No progress in gonadal maturity was observed with this species in the laboratory on the diet supplemented with EmDHA.