Understanding of spatial extent, infection window and potential alternative hosts for the oyster disease QX in Port Stephens
Seafood CRC: industry management and commercialisation plan for the Sydney rock oyster breeding program
The success of FRDC supported breeding and hatchery production programs has demonstrated to industry that faster growing disease resistant oysters can be bred and distributed. Industry has now established a company, SOCo, to accept responsibility for the management, future development and distribution of the SRO breeding lines. Initially the company undertook management and coordination of the sales of faster growing seed and now wishes to expand its role to determine the future of the breeding program. To ensure the successful adoption of technology, a previous FRDC review of oyster hatchery and breeding programs (Benzie et al., FRDC 2001/213) strongly emphasised the need to inform, equip, and assist industry to understand and adopt this technology. Accordingly, there is a need to 1) conduct an independent assessment of current selection practices and their relevance to ongoing breeding line maintenance and improvement, 2) establish the genetic status of the current breeding lines with respect to the natural populations of SRO and 3) assist in the development of cost effective strategies and technology for the maintenance of selected lines and their genetic integrity. The outcomes of these assessments need to be presented in a form that is suitable for incorporation in the company’s business plan and that would be of value to other industries undertaking or contemplating breeding programs.
Improved understanding of Tasmanian harmful algal blooms and biotoxin events to support seafood risk management
Seafood CRC: securing and enhancing the Sydney rock oyster breeding program
The SRO industry has the potential to exploit new export initiatives and increase production. Any resurgence in the industry will depend on SOCo’s ability to manage the development and supply of selectively bred oysters. FRDC has fostered this process by supporting breeding programs and hatchery research, whilst encouraging industry management of technology. The Benzie Report, Oyster Research Advisory Committee (ORAC) R&D Strategic Plan and the Action Plan developed at the FRDC-funded QX workshop in June 2005 have all indicated that effective management strategies for the SRO industry must be underpinned by; 1) the continued development of oyster husbandry techniques to secure QX resistant breeding lines, and, 2) the identification of genes associated with QX disease resistance that can be used for marker-assisted selection. These complementary research goals represent a critical step in “QX proofing” NSW estuaries against ongoing and catastrophic QX disease outbreaks. Continued research may also allow farming to be re-established in areas abandoned because of QX disease. Integration of genetic markers and single pair mating into the hatchery-based breeding program will increase the efficiency of selection, and decrease the number of generations required to establish true breeding resistant lines. Without marker assisted selection, the breeding program may not reach its full potential in time to prevent further losses.
A comprehensive presentation on the SRO industry will be given during the FRDC board’s visit to Port Stephens in July 2006.
Final report
The Select Oyster Company breeding plan has been amended to include a comprehensive manual of protocols for pair mating Sydney rock oysters (4.1). The association between phenoloxidase (PO) and QX resistance has been confirmed and a sensitive test for PO genotypes has been developed so that the breeding program has a tool to genotype parents and large numbers of their progeny to assist breeding (4.2-4.8). Protocols for cryopreservation of gametes have been developed and documented as a potential strategy to reduce SOCo’s overall maintenance costs for the lines and increase genetic security (4.9). Non-chemical means of triploidy induction in SRO (temperature and pressure shock) were tested (4.10). While these techniques were not as effective as existing chemical induction techniques, they have formed the basis of ongoing research to see if efficacy can be increased. A total of 60 pair mated family lines, including 31 lines with differing PO phenotypes, have been produced and are undergoing performance assessment in the field. These families will be made available to SOCo for incorporation in the industry breeding program.