Risk from Diarrhetic Shellfish Toxins and Dinophysis to the Australian Shellfish Industry
Valuing Victoria's Wild-catch fisheries and aquaculture industries
Future oysters CRC-P: Polymicrobial involvement in OsHV outbreaks (and other diseases)
Social and economic evaluation of NSW coastal commercial wild-catch fisheries
Safeguarding commercial fishing in NSW from ciguatera fish poisoning
CFP is an illness caused by consumption of fish that have accumulated ciguatoxins (CTXs), which are naturally produced by marine microalgae (Gambierdiscus spp), and not degraded by freezing and heating processes. It is well known from Queensland, with more than 1000 cases in the past 15 years, including 2 fatalities, despite only ~20% of cases reported. Around 90 species of fish can be contaminated with CTXs, which accumulate, and are often associated with larger and carnivorous fish. Species of Gambierdiscus may be invasive: internationally, increases in abundance and expansion into new areas have occurred. Our recent work (shown in http://theconversation.com/explainer-what-is-ciguatera-fish-poisoning-21835) has now found Gambierdiscus spp is present in NSW.
No study has been conducted on the presence of CTXs in fish from NSW, and knowledge about its distribution within Australian waters is poor. The recent illnesses at Scotts Head and Evans Head show that CTX may occur in fish caught in NSW. The NSW Food Authority has advised the public not to eat Spanish Mackerel weighing over 10 kg, based on the Sydney Fish Market management plan, which restricts the sale of fish based on size limits, high-risk species and location where fish were caught. However, no data exist regarding sizes, location and risk from Spanish Mackerel in NSW. Smaller Spanish Mackerel may represent a potential risk. However, these guidelines may be excessively restrictive, as some of the fish discarded may be safe for consumption.
We are now able to quantify marine biotoxins in Sydney using a newly obtained LC-MS, and links with a group of collaborating experts. We propose to undertake a thorough sampling and testing program to determine the presence of CTXs in Spanish Mackerel (Scomberomorus commerson) from NSW, to provide the baseline data necessary for the revision of guidelines for the management of CFP in NSW.
Final report
Aquafin CRC - Atlantic Salmon Aquaculture Subprogram: development of an AGD vaccine: phase II
Health is one of the major issues associated with intensive culture industries, including aquaculture. Unhealthy stock relates to unhealthy industry – higher production costs, reduced viability, poor market and public image. Outbreaks of infectious salmon anaemia (ISA) in Scotland resulted in some salmon companies going into receivership. The use of medication increases production costs and negatively impacts on the market.
In Australia, salmon aquaculture is relatively disease free, which provides a possible marketing advantage. However, Amoebic Gill Disease costs are 9.4% of the gross value of production; a significant production cost for farming Atlantic salmon in Tasmania. The disease outbreaks seem to intensify as the industry develops and now are prevalent not only during summer months but also in winter. Outputs of the CRC Health Program such as improved treatment of AGD infected fish, AGD risk forecasting ability and vaccine production against AGD will increase the profitability and competitiveness of the Australian salmon industry.
AGD is severely limiting further expansion of the industry because it ties up resources that could be directed elsewhere, and it limits farming sites due to reliance on freshwater for bathing. Current treatment of AGD while environmentally friendly is not viable in the long-term and alternatives are required. Other treatments may be more reliant on antibiotics or chemicals, a risk to the image of the industry. Although vaccine development can be seen as a high-risk research target the potential rewards justify the risk