In recent years, Maine bivalve hatcheries have attempted to produce a consistent supply of Atlantic sea scallop (Placopecten magellanicus) juveniles, but they continue to experience sudden mass mortalities of larval scallops with unknown causes. The immune system plays a critical role in protection against foreign substances, such as pathogens. There is currently a knowledge gap about the sea scallop immune system and its development during vulnerable larval stages. Further research on sea scallop immune ontogeny and immunocompetence can provide insight into underlying reasons behind the mass mortalities and what types of immune functions are available for larval protection.
This project seeks to understand the immune ontogeny and immunocompetence of hatchery-raised sea scallop larvae through gene expression analysis of immune markers and its relevance to larval survival and hatchery related events. Several genes related to immune function have been identified, such as ferritin, and amplified through RT-qPCR using sea-scallop specific primers. Expression patterns of immune-related genes were measured at various stages (early D-stage veliger through early pediveligers) in larval samples collected from a Maine hatchery. This could reveal insight into how larvae are interacting with the hatchery environment, when coupled with hatchery data. In addition, transcriptomic analysis of bacterially challenged adult sea scallops is underway and should provide further information about how sea scallops respond to a pathogenic Vibrio species. Vibrio are common hatchery pathogens. Knowledge about the immune system development and events during larval development in the hatchery environment can be used to improve management processes, which could then improve larval survival.