Revision of the existing AQUAVETPLAN: ‘Viral Encephalopathy and Retinopathy Disease Strategy Manual’
ABFA IPA: an assessment of the risk of exotic disease introduction and spread among Australian Barramundi farms from the importation of Barramundi products
Aquatic Animal Health and Biosecurity Subprogram: Disinfection measures to support biosecurity for infectious spleen and kidney necrosis virus (ISKNV) at aquaculture facilities
Aquatic Animal Health Subprogram: further research and laboratory trials for diagnostic tests for the detection of A invadans (EUS) and A astaci (Crayfish Plague)
Development of sector-specific biosecurity plan templates and guidance documents for the Australian farmed barramundi industry
Enhanced biosecurity has been identified as a priority area in the ABFA 2015 – 2020 Strategic Plan.
Although the farmed barramundi industry and relevant jurisdictions have implemented a range of measures to mitigate the risks of major diseases of concern (i.e. individual on farm biosecurity procedures and engagement and sponsorship of a number of specific projects), this industry sector does not have a nationally consistent, agreed approach to biosecurity.
The development of a sector-specific national biosecurity plan for the farmed barramundi industry would ensure a common level of biosecurity risk management to support specific enterprise and whole-of industry productivity.
Furthermore, work is underway to develop industry-government emergency aquatic animal disease response arrangements. These arrangements should be underpinned by amongst other measures an industry biosecurity plan.
The industry feel that they are at a high risk to diseases introduction through the importation of fish that require processing from high risk regions that have very potent diseases such as pot belly and scale drop syndrome. As such enhanced Industry biosecurity measures are considered critical to the growth of barramundi farming in Australia.
Report
These guidelines have been developed to assist Australian Barramundi farms with the tools and templates to create basic through to comprehensive, and fully auditable, biosecurity plans.
Symposium on parasitic diseases of aquatic animals: 10th International Congress of Protozoology
Aquatic Animal Health Subprogram: the production of nodavirus-free fish fry and the nodaviruses natural distribution
Nodavirus in wild barramundi populations
* There is a need to address concerns about the effect of stocking hatchery-reared barramundi on the level of unapparent nodavirus infections (that is, the prevalence) in wild barramundi.
* The first step is to determine the prevalence of nodavirus in wild populations of barramundi (that is to say the natural level of nodavirus-carrier status – an infection without disease).
* The baseline nodavirus prevalence data will permit:
- comparison of barramundi populations in areas where stocking has or has not occurred,
- assessment of changes in prevalence of nodavirus in future years,
- effective decisions about appropriate sources of replacement broodstock for breeding programs.
Nodavirus in freshwater fishes
* There is a need to address concerns about the risk of possible lethal transmission of barramundi nodavirus to freshwater fishes.
* Recent investigations have shown a possible susceptibility of freshwater fishes to barramundi nodavirus and that nodaviruses naturally occur in species other than barramundi in Australia, including the freshwater species, sleepy cod.
* There is a need to determine if there are nodaviruses in freshwater fishes as a risk analysis for translocation should include disease-status information in the receiving population.
Are the nodaviruses found in freshwater fishes related to barramundi nodavirus?
* If nodaviruses are detected in freshwater fish an analysis of relatedness (sequence analysis of PCR products) could indicate an association to previous stocking in that area of hatchery-reared barramundi. This information would support effective risk analysis for future translocation considerations.
A testing protocol for hatchery production of nodavirus-free fish fry.
* Broodstock screening protocols to identify nodavirus-free broodstock have been described from overseas but the detection tests used then are not as sensitive as the two-step or nested RT-PCR, and the protocols include a requirement for egg/water disinfection and repeat testing of larvae.
* There is a need to evaluate and validate the sensitivity of the two-step or nested RT-PCR to identify nodavirus-free broodstock and to determine if one or more tests are required to confirm the nodavirus-free status.
* There is a need to confirm in barramundi that larvae/fry become infected by nodavirus through the vertical transmission route (ie., from their parent(s)).
* There is a need to determine if fry can become infected via nodavirus-contaminated water once they are stocked into nursery systems.
* If the vertical infection route is the same for all fish species, the information on the testing protocol required to produce nodavirus-free barramundi fry will be a model testing protocol applicable to all fish species in breeding programs in Australia.