The expansion of the Tasmanian Salmonid Industry in new growing areas, such as Storm bay, is contingent on demonstrating that further development is done in a responsible and sustainable way. This is central to maintaining public confidence in the salmon industry. Demonstrating best practice in environmental sustainability requires that the environmental footprint of the industry is well understood and contained within acceptable levels. An environmental monitoring program that assesses the environmental performance of farming at both local and system wide scales will provide this understanding, enabling appropriate regulatory responses. The development and validation of a biogeochemical model that can estimate the natural systems capacity to assimilate salmonid derived nutrient inputs at both local and broader system scales provides the capacity to both understand current environmental conditions and forecast the environmental responses under alternate management responses. This combination of a reliable and “fit for purpose” environmental monitoring and modelling program will help meet the needs and expectations of a science based adaptive management framework necessary for the proposed development of salmonid farming in Storm Bay.

The 5 July 2017 meeting of representatives from the various States involved in the Murray Cod industry agreed to three key R&D priorities to support expansion of the Murray Cod industry in Australia. They included:

1. Development of a farm management plan/manual to: provide advice on optimising production systems and water quality; review and update of existing Murray Cod culture guidelines using recent relevant publications and input from commercial operators; and identify any information gaps
2. Off Flavour. Review of recent publications/work from other sectors (eg Barramundi) to prevent off flavor in Murray Cod. Murray Cod quality product assurance; and
3. Fish health and treatment (parasites, bacterial infection, Lurnea, Chilodonella, ratty tail). Review and update information on treatment options (chronic/prophylactic) for Murray Cod. Murray Cod health management strategy

This project proposal aims to address these high R&D industry priorities by developing a range of technical and extension material.

The Murray Cod industry is developing rapidly in Australia increasing from 250t 2014/15 to over 500t 2016/17. Industry forecast several thousand tonnes production by 2020 with many new farms seeking approval and new franchise business models moving forward. To capitalise on this expansion, there is a pressing need to improve extension resources.

Following basic epidemiology principles, no infectious disease occurs ‘randomly’ and its occurrence follow logical and predictable patterns. The presence of an infectious agent is unlikely sufficient to explain these patterns and most aquatic diseases result from the complex interaction between the agent, the host and its environment. Therefore, the targeted outcome for a POMV control plan is threefold:
1. Decrease transmission between infected and susceptible fish groups – this requires identifying risk factors associated with the introduction, spread, and maintenance of the pathogen within the industry;
2. Decrease the number of susceptible fish – this mainly requires identifying risk factors associated with the susceptibility of the host (e.g. husbandry-related stress) and the development of a safe and effective prophylaxis;
3. Decrease the amount of virus in the environment - this requires detecting infected fish cage(s) early to implement timely control strategies.
Diagnostic capacity to confirmed POMV outbreak has been developed and is currently used in routine by the industry. A vaccine against POMV is currently under development at the Tasmanian Aquatic Animal Health and Vaccines Centre of Excellence and will be available in the future. However, little is known about risk factors specific to POMV and about its full economic impact. We define as a ‘risk factor’ any attribute of the agent, the host or its environment that increases the risk and intensity of a disease outbreak. Most of the environmental risk factors (including farming practices) facilitate the introduction, transmission, or maintenance of the pathogen; while the host risk factors affect the susceptibility of the host and its capacity to become diseased. Like the closely related ISAv, the magnitude and occurrence of POMV outbreaks appeared to be highly variable. This supports the existence of additional factors other than the POMV infection that contribute to the intensity of an outbreak. It is anticipated that by identifying and intervening on some of the manageable risk factors, the frequency and the severity of POMV outbreaks can be reduced.