SUBZERO TEMPERATURE STORAGE OF FISH EGGS FOR IMPROVED HATCHERY OPERATIONS

Culturing fish today is organized around two key steps: multiplication of fish in the hatcheries and the increase of fish biomass in grow-out production. This transition is more-or-less linear: immediately after spawning eggs get fertilized, develop and hatch, they are grown to the fry/fingerling/smolt stage, and get transferred to grow-out production. This cycle starts with the spawning event, which mostly is beyond the control of the hatchery managers and dictates when the cycle will end. Therefore, there is limited control over breeding and reproductive operations at the hatchery. This project is proposing a solution to this problem by developing a way to store eggs for extended periods of time in subzero temperatures. The ability to store eggs for extended periods of time at subzero storage will (i) extend egg availability beyond spawning seasons and increase hatchery utilization, (ii) enable synchronization of hatchery operations through on-demand access to eggs, (iii) facilitate transport of eggs for long distances, which is cheaper and safer than shipping fry.We propose an investigation into commonly employed freezing solution additives to establish relationship between their concentration, temperature and potential for extending subzero storage duration of salmon eggs. Out of the relationships, guidelines for additive dosage and storage temperature will be established for direct application to existing subzero storage processes. The ultimate goal of the project is to develop proof-of-concept development of 4-6 week egg storage technique.