Although the abalone and oyster industries and relevant jurisdictions have implemented a range of measures to mitigate the risks of major diseases of concern (i.e. AVG, POMS), both industry sectors still lack a nationally consistent, agreed approach to biosecurity.

An industry-wide biosecurity plan is a critical component of health accreditation programs to facilitate safe interjurisdictional and international trade in aquatic animals. Minimum biosecurity standards must meet importing jurisdiction or country requirements, so it is vital that these plans are recognised by state government authorities and implemented by industry. Note that for interstate trade, requirements generally outline that oyster or abalone livestock only be sourced from land-based facilities with high level (auditable) biosecurity.

The abalone industry require movement of broodstock between farms to improve genetic family lines. A national Abalone Health Accreditation Program (developed by SCAAH) provides guidance for land-based abalone farms to demonstrate freedom of AVG for the purpose of trade. Biosecurity and surveillance requirements form the basis of the health accreditation program. A nationally agreed biosecurity plan (guidance document) specific to land-based abalone farms, which identifies specific disease risks and provides recommended systems to mitigate those (and potential emergent) risks, is now required to assist farmers in developing their own farm biosecurity plans.

Similarly, for the oyster industry both biosecurity and surveillance are required to demonstrate freedom of POMS (and mitigation of potential other emergent biosecurity risks). This is particularly important for consideration of movement of hatchery reared spat (juveniles) from areas of known infection to areas not known to be affected by POMS. These two fundamental requirements (biosecurity and surveillance) are outlined in South Australia’s draft import protocols for spat sourced from oyster hatcheries. Nationally agreed guidelines for oyster hatchery biosecurity plans are now required to facilitate trade in oyster spat.

Oyster growing areas with reticulated sewage and/or waste water treatment plants (WWTP) in the catchment are all potentially affected by closures caused by sewage spills and overflows. Standard risk management practice following such events is to instigate a 21 day closure resulting in lost production, market share, reputational damage, and potential recall costs. The number of growing area closures related to sewage spills and overflows in Australia is significant. In NSW, harvest areas were closed on 100 occasions due to sewage spills between July 2009 and June 2014, resulting in 2688 days of lost sales. The use of FRNA phage as potential indicators of human enteric viruses could lead to a 50% reduction in the number of days closed.
In Tas, there have been 75 harvest area closures of greater than 21 days relating to sewage spills over the past 5 years, resulting in at least 1575 days of lost sales. One three week closure in the Pittwater growing area is estimated to cost approx. $250-$400k combined sales, depending on the season. The cumulative impact of these spills has been estimated to reduce the value of businesses by a combined value of $12 million. Not all sewage incidents result in human enteric viral contamination of shellfish. Factors such as the level of illness in the community, treatment level of waste, size of the spill, hydrodynamics of the growing area, and local growing area conditions all influence the whether a spill results in significant contamination of oysters. FRNA phages have not been used routinely as indicators in shellfish in Australia to date. If FRNA phage levels show contamination is negligible, regulators may allow re-opening of growing areas as early as 10 days after the spill following results from testing on day 7, significantly decreasing the cost of spills to growers. FRNA phages are also showing potential as general indicators of human pathogenic risk.

In the long term the POMS Resistance Breeding Levy will secure the future of ASI and by extension selective breeding for Pacific Oysters. This in turn secures the investments made over many years by federal funding agencies. Due to delays achieving unanimous stakeholder support the approval for the levy has been later than anticipated but was formally adopted and implemented from October 13, 2014. As a result of this delay ASI is not in a position to enter into some key contracts in terms of provision of services for current data sets. The most pressing of these is the provision of genetic services undertaken by CSIRO.

The support from CRC for this activity will open up an training opportunity we would like to offer. There are a number of other participants in the CRC who are initiating family breeding programs or planning to initiate these programs. This project thus presents the opportunity of conducting the analysis as a training exercise for CRC participants including key stakeholders in the oyster breeding programs to improve understanding of the process and logistics of implementing family breeding program.