Understanding the dynamic of POMS infection and the role of microbiota composition in the survival of Pacific oysters, Crassostrea gigas

In New Zealand, mass mortality episodes associated with OsHV-1 have been recorded in juvenile C. gigas since 2010 and selective breeding to improve resistance to OsHV-1 has been effectively used to mitigate the impact of the disease. However, POMS infection process and the role of the host-microbiota during infection have still not been well established in NZ. Using a laboratory-based experimental infection approach, we challenged ten full-sib oyster families with previously established contrasted genetically based ability to survive POMS in the field. Molecular analyses (viral load quantification, viral gene expressions and 16S rRNA gene sequencing) were combined with histopathological observations to describe the temporal kinetics of infection to POMS and to characterize the role of microbiota during infection.