The Australian farmed Barramundi is estimated at over $37.1 million AUD with a production of over 3,772 tonnes annually (Savage, 2015). The value of the wild-catch sector was estimated to be $9.9 million AUD with 1,073 tonnes produced (Savage, 2015). These sectors of the industry as well as recreational and Indigenous fishers, are all at risk of being exposed to hazards potentially introduced by imported Barramundi and grouper products, which could pose significant consequences. The Australian Federal Department of Agriculture does not consider there is sufficient evidence to suggest that the import conditions for uncooked barramundi do not effectively manage the risk of pests and diseases of concern arriving in Australia. Until further evidence is generated to demonstrate that importation of uncooked barramundi products poses a risk that exceeds Australia's Appropriate Level of Protection, then regulatory actions to mitigate these perceived biosecurity risks are unlikely to be implemented. Risk mitigation requirements for importation of whole farmed barramundi include that the exporting country must, among other things, declare it has in place health surveillance and monitoring and that the fish were not derived from a population slaughtered as an official disease control measure. However, this self-declaration is not supported by rigorous testing to ensure compliance. There are current and have been no previous protocols in place to test for the target iridoviruses in imported barramundi and grouper product, so the efficacy of the existing import controls has not been subject to assessment at retail level. Sampling at retail outlets of uncooked whole and eviscerated barramundi and grouper commodities is proposed in order to better assess the efficacy of import conditions. This project will focus on determining the presence or absence of exotic virus genetic material in imported uncooked potential high risk barramundi and grouper commodity. Should any positive genetic material be detected confirmatory re-testing will be performed in order to reduce the risk of a false positive PCR test result and a subsequent project will be prepared o

Diagnostic laboratories across the country vary in their diagnostic capability for aquatic animal pathogens. Due to their individual needs, many diagnostic laboratories have developed their own reagents and procedures for the identification of bacterial pathogens. This lack of standardisation can be problematical, for example, when reporting on aquatic animal health status. Using Vibrio identification as an example, it is likely that diagnostic laboratories would be capable of identification to the genus level (i.e. Vibrio sp.). However, due to differences in the various laboratories, identification to the species level would be difficult, and different laboratories are likely to use different procedures for identification.

There is a clear need for diagnostic scientists working in this area to compare and standardise protocols between States. A series of workshops aimed at providing training in the diagnosis of bacterial disease in aquatic animals for those new to the area, and at the same time providing an opportunity to evaluate the various diagnostic protocols used in Australia for their ability to identify both enzootic and exotic pathogens is overdue.

Development of Standard Diagnostic Techniques will require three logical steps:

1. Comparison and evaluation of the tests currently used by diagnostic laboratories;
2. Development of, and agreement on, the most sensitive, accurate and reproducible methods;
3. Adoption and publication of the agreed method for each pathogen as the Standard Diagnostic Technique.

Thus development of SDTs in aquatic animal bacteriology may include an SDT on general methods for aquatic animal bacteriology followed by SDTs for specific diseases such as Vibriosis. Vibriosis, due to its widespread occurence in vertebrate and invertebrate aquatic animal species in tropical and temperate regions of Australia, was identified as a disease of particular importance with respect to standardisation of diagnostic methods [1].

In order to ensure that the SDTs incorporate the latest technologies and information on exotic, as well as enzootic, bacterial pathogens, and that the SDTs will be recognised internationally as state-of-the-art, an international expert on the specific disease will be invited to participate in each of the respective workshops.

References

1. Fish Health Management Committee (1998). Report of the Fish Health Management Committee and the Fish Health Coordinating Group: Workshop on Aquatic Animal Health: Technical Issues, 7-9 December 1998, Melbourne, Victoria.