During the last two decades a number of disease outbreaks have led to mass oyster mortalities and the closure of several oyster-harvesting regions, resulting in multi-million dollar losses. These outbreaks mirror a global pattern of increased aquaculture disease, with disease emergence potentially linked to environmental degradation (pollution) and climate change related processes, such as rising seawater temperature. Within NSW estuaries, multiple microbiological agents have been implicated in oyster diseases, but a clear understanding of the ecological and environmental drivers of disease outbreaks has remained elusive. This means we cannot predict when outbreaks will occur, making it very difficult to manage infection events and develop strategies to mitigate future oyster disease events.
Since 2008, Pacific Oyster fisheries in several parts of the world have been decimated by the influence of Pacific Oyster Mortality Syndrome (POMS), resulting in high (>95%) rates of juvenile oyster mortality. Recent evidence indicates that POMS is a polymicrobial syndrome, that is not only caused by the OsHV-1 virus, but includes the involvement of pathogenic bacteria from the Vibrio genus, a bacterial group comprising species that cause disease in a diverse range of marine animals and which is responsible for significant mortality in a variety of aquaculture industries. However, our understanding of this complex interaction is limited.
This project will provide valuable insights into the microbial communities associated with oysters, how those communities vary and how they might influence the course of other diseases. The project will also indicate whether breeding influences the microbial communities associated with oysters and whether this is influencing the impact diseases like OsHV is having on different Pacific oyster families.
future efforts hoping to employ the oyster microbiome for diagnostic purposes.