2012/713 Understanding conditioning of Sydney Rock Oysters

By Abigail Elizur et al.

Critical in the production and marketing of Sydney Rock Oysters (SRO) is their physical and reproductive condition. While cycles in SRO condition are broadly understood, and to some extent can be manipulated through gross environmental changes, our understanding of the biochemical processes underpinning changes and our capacity to monitor these changes is limited. The strong demand for the selectively bred SRO has created both challenges and opportunities for the entire industry. Oysters ready to spawn are required for hatchery production; however, it is also at such condition when the oysters’ market price is at its highest. The challenge for the SRO aquaculture industry is heightened by the observed deviation of the reproductive behaviour of the selectively bred SRO from their wild counterpart.

This project set out to identify Sydney Rock Oyster neuro peptides that affect reproduction in order to develop technologies for improving reproductive condition and spawning. They identified a suite of peptides which, based on studies in other species, are likely to have a role in reproduction, and tested some of these for their capacity to induce a physiological response and spawning. The results clearly demonstrated that neuropeptide genes are conserved in bivalves, however, there are distinct differences with other molluscs. Despite a sessile mode of life and thus less intricate patterns of behavioural events, oysters have obviously retained a repertoire of neuropeptides with a complexity similar to that of other mollusc classes. The number of peptides predicted in this study supports the power of genome mining for neuropeptide gene discovery, and provides a strong foundation for future in silico investigations within oysters.