The Sydney rock oyster Saccostrea glomerata (Gould 1850) breeding programme: progress and goals

Abstract

In 1990, NSW Fisheries initiated a mass selection programme in Port Stephens, NSW, with the aim of breeding faster growing Sydney rock oysters Saccostrea glomerata (Gould 1850). After two generations of selection, an average weight for age advantage of 18% (range 14±23% per breeding line) was achieved. This equates to a reduction of 3 months in the time taken to reach market size. Experiments are planned to determine how much of this 3 months advantage is additive to the 6 months advantage this laboratory has already obtained using triploid S. glomerata. A parallel set of S. glomerata breeding lines was established on the Georges River, NSW, to include selection for resistance to the protistan parasite Mikrocytos roughleyi, the causal agent of winter mortality. The programme was disrupted by the outbreak of QX disease Marteilia sydneyi, another protistan parasite, in 1994. In 1997, the breeding programme was reorganized and expanded. New lines were bred from oysters that had survived both QX and winter mortality. After one generation, a small improvement in resistance to QX has been recorded; however, the exposure of further generations to M. sydneyi will be required to con®rm an increase in resistance.

Marteiliosis in molluscs: A review

“…by genetic selection have been made although observations suggest that the biological basis exists (Fuentes et al 2002). In Australia, preliminary reports on resistance to M. sydneyi through mass selection of surviving hosts have been made (Nell et al 2000), with first generation improvement recorded but additive resistance of successive generations yet to be confirmed. Peters and Raftos (2003) correlated physiological immuno-suppression (a drop in levels of the protein phenyloxidase) to infection with M. sydneyi.…”

Fish and Shellfish Diseases Caused by Marine Protists

“…Recently, a strain of Sydney rock oyster resistant against M. sydneyi has been established and used for empirical research of aquaculture (Nell et al 2000 ).…”

Disease Prevention Strategies for QX Disease (Marteilia sydneyi) of Sydney Rock Oysters (Saccostrea glomerata)

“…In January 1997, the breeding program was reestablished in the Georges River and modified to incorporate selection for resistance to QX disease using mass selection from the survivors of the Georges River fast growth lines (Nell et al 2000). Continuous improvement in QX disease resistance has been observed for each generation of S. glomerata selected for QX resistance (Nell & Perkins 2006), suggesting to date that QX resistance is controlled by multiple genes and is heritable in S. glomerata.…”

“…A breeding program to develop fast-growing S. glomerata was established by I&I NSW in 1990 (Nell et al 2000) and is now in its 7th generation. Progress in selection for fast growth and disease resistance to winter mortality (Bonamia roughleyi) in the Georges River was severely interrupted when QX disease occurred in that estuary in 1994 (Adlard & Ernst 1995).…”