The SRO micobiota associated with a QX disease

The Sydney rock oyster (SRO; Saccostrea glomerata) is the most intensively farmed oyster species in Australia however, diseases such as Queensland unknown (QX) disease has caused substantial losses and impeded productivity. The parasite, Marteilia sydneyi, is the aetiological agent of QX disease, and like other diseases outbreaks are likely driven by a series of complex environmental and host factors, such as salinity and oyster genetics. A potential but understudied factor in QX disease is the role of the SRO-associated bacterial community, which we sought to examine prior to and during a QX disease outbreak. Using 16S rRNA amplicon sequencing, we examined the bacterial community associated with four SRO families from the breeding programme deployed in a region where QX disease occurs, with sampling conducted fortnightly over 22 weeks.