Pathogenic Vibrio Parahaemolyticus In Australian Oysters
Funder
Fisheries Research and Development Corporation
Funding Amount
$13,995.00
Summary
In 1999, Seafood Services Australia (SSA) initiated a risk-based approach to assessing and managing hazards. Regarding oysters, two risk assessments were undertaken, one on viruses and one on vibrios. Focusing on the latter hazards, the risks associated with the three main species: V. parahaemolyticus, V. vulnificus and V. cholerae were assessed. It was noted that V. parahaemolyticus (Vp) has recently caused major outbreaks in USA from consumption of oysters due to a “new” pathogenic type O3:K6. ....In 1999, Seafood Services Australia (SSA) initiated a risk-based approach to assessing and managing hazards. Regarding oysters, two risk assessments were undertaken, one on viruses and one on vibrios. Focusing on the latter hazards, the risks associated with the three main species: V. parahaemolyticus, V. vulnificus and V. cholerae were assessed. It was noted that V. parahaemolyticus (Vp) has recently caused major outbreaks in USA from consumption of oysters due to a “new” pathogenic type O3:K6. For Australia, no work on pathogenic Vp in oysters could be found, which introduced a great deal of uncertainty to the assessment. The RA noted that there had been two Vp poisonings in NSW from prawns imported from Indonesia, the clear inference being that pathogenic Vp exists in neighbouring waters.
In March, 2002 the FAO/WHO team will develop a global risk assessment of Vp in oysters. The RA will utilise the US risk model and insert data from the oyster industries of Canada, New Zealand, Australia and Japan. If no Australian data are available on levels of Vp the modellers will make assumptions which may well be disadvantageous to the Australian industry. This could happen if the north American mitigation strategy (rapid icing) to control of Vp is adopted as a prerequisite for export.
Failure to input Australian data into a Codex global risk assessment could have serious consequences for the industry. At best it would lead to protracted negotiation between Australia and Codex. These negotiations would need to be science-based and a research program would need to be funded. It is probable that the scale of this investigation would be at least a log scale larger than the present application.
Among the strategies to mitigate V. parahaemolyticus risk is chilling oysters as early as possible after harvest. In the case of the Canadian industry in British Columbia, the strategy has been used successfully in the summers of 2000 and 2001. This strategy is directly opposed to current summer handling practices by the NSW industry which allows product to remain as warm as 25°C for up to three days.
This project is designed to provide evidence of the occurrence and prevalence of pathogenic and non-pathogenic V. parahaemolyticus in Australian oysters. This knowledge will be invaluable to the NSW industry in particular - in case the FAO/WHO assessment recommends chilling of oysters as a pre-requisite for market access.
Effect of not doing the proposed study
If the work is not done and Codex Committee on Food Hygiene (CCFH) recommend a mitigation strategy of rapid icing, the local industry has a number of choices:
1. Ignore the CCFH recommendation on the grounds that we don’t export large volumes of oysters. The problem with this approach is that Codex has just as much application and force for domestic production as it does in the export arena.
2. Undertake a study to try to show that there is no problem with V. parahaemolyticus from Australian product. This would probably be a larger study than the present one and would be mounted to attempt to gain exemption for Australia. It’s always difficult to unwind global hygiene edicts.
The present project, for a relatively modest investment, effectively places Australian data into a global risk assessment. As such the data will have great force in the modelling phase. xbad Objectives: 1. Obtain total Vibrio spp. and total V. parahaemolyticus counts from oysters from NSW, SA and Tasmania. 2. Determine prevalence of pathogenic V. parahaemolyticus amongst these isolates. 3. Compile and analyse data for potential inclusion in the FAO-WHO global risk assessment of Vibrio parahaemolyticus in oysters. Read moreRead less
Revision Of The AQUAVETPLAN Operational Procedures Manuals For Disposal And Decontamination
Funder
Fisheries Research and Development Corporation
Funding Amount
$31,500.00
Summary
The Department of Agriculture and Water Resources is seeking expressions of interest for the revision of the following AQUAVETPLAN Operational Procedures manuals: 1. Decontamination 2. Disposal The Australian Aquatic Veterinary Emergency Plan (AQUAVETPLAN) is a series of manuals that outline Australia’s approach to national disease preparedness and propose the technical response and control strategies to be activated in a national aquatic animal disease emergency.
The Decont ....The Department of Agriculture and Water Resources is seeking expressions of interest for the revision of the following AQUAVETPLAN Operational Procedures manuals: 1. Decontamination 2. Disposal The Australian Aquatic Veterinary Emergency Plan (AQUAVETPLAN) is a series of manuals that outline Australia’s approach to national disease preparedness and propose the technical response and control strategies to be activated in a national aquatic animal disease emergency.
The Decontamination manual was first published in 2008, and the second version of the Disposal manual was published in 2009. Both manuals require revision to reflect new scientific knowledge, and to ensure that decontamination and disposal procedures used for disease control purposes reflect current ‘best-practice’ approaches. Objectives: 1. Review and deliver updated AQUAVETPLAN Operatinal Procedures Manuals for decontamination and disposal. Read moreRead less
Investigating Aetiology And Risk Factors Of Ocular Lesions And Associated Mortality In Ranched Southern Bluefin Tuna
Funder
Fisheries Research and Development Corporation
Funding Amount
$200,238.00
Summary
This year (2017), some of the ranching operations reported the increased cumulative mortality. In some severe cases, up to 90% of collected mortalities present some degree of unilateral or bilateral ocular damage ranging from corneal cloudiness, with or without ulcers, up to complete perforation. The anecdotal report of eye lesions has progressively increased since the 2015 season without a definitive cause being identified. Previous reports (Rough et al., 1999; Rough, 2000; Hayward et al., 2007 ....This year (2017), some of the ranching operations reported the increased cumulative mortality. In some severe cases, up to 90% of collected mortalities present some degree of unilateral or bilateral ocular damage ranging from corneal cloudiness, with or without ulcers, up to complete perforation. The anecdotal report of eye lesions has progressively increased since the 2015 season without a definitive cause being identified. Previous reports (Rough et al., 1999; Rough, 2000; Hayward et al., 2007; Hayward et al., 2008a; Hayward et al., 2008b; Hayward et al., 2009; Hayward et al., 2010; Hayward et al., 2011, including FRDC projects No 2003/225 and 2008/228, Nowak et al., 2007; Nowak et al., 2012) identified sea lice of the genus Caligus spp. as a differential cause of eye lesions in SBT. The copepod ectoparasite is thought to damage the eyes by feeding on the cornea epithelium of infested SBT. Lesions worsen when fish flash against the cage’s net to dislodge the itchy copepods. Partial or full vision loss is suspected to impair the capacity of the fish to compete for feed and to result, with time, in the death of affected fish. At this stage, it is unclear: 1 - what is the distribution of the observed increased mortality across the industry; 2 - what is the occurrence and severity of eye lesions across the industry; 3 - if the observed increased mortality is entirely attributable to eye lesions; 4 - if eye lesions are solely caused by C. chiastos or if other causes are involved; 5 - if potential tow-, cage-, and fish-level risk factors are associated with the occurrence of eye lesions and its cause(s). Objectives: 1. Estimate the frequency and distribution of increased mortality across the industry. 2. Describe the pathology and severity of eye lesions and estimate the frequency and distribution of these lesions across the industry. 3. Investigate potential tow-, farm-, and fish-level risk factors associated with increased mortality and eye lesion occurrence. 4. Investigate the putative role of sealice in causing this episode of eye lesions. Read moreRead less
The Pearl Oyster (Pinctada Maxima): A Histological Atlas Of Normal And Diseased Tissues
Funder
Fisheries Research and Development Corporation
Funding Amount
$45,000.00
Summary
Pearl production accounts for more than half the value of the combined Australia aquaculture industries, yet little was understood of their health status prior to project no 94/79.
There is no text available which describes, the anatomy and histopathologically of the pearl oyster, Pinctada maxima , or the histopathological changes that occur with disease. This lack of published data is compounded by the fact that there are currently only 4 pathologists in Australia with significant expe ....Pearl production accounts for more than half the value of the combined Australia aquaculture industries, yet little was understood of their health status prior to project no 94/79.
There is no text available which describes, the anatomy and histopathologically of the pearl oyster, Pinctada maxima , or the histopathological changes that occur with disease. This lack of published data is compounded by the fact that there are currently only 4 pathologists in Australia with significant experience and knowledge to interpret histology sections from pearl oysters.
The publication of the histopathology photographs collected during project no 94/79 plus other reference material collected by previous researchers will help to overcome this problem.
The ability to be able to recognise what is normal or abnormal is critical in the interpretation of histology sections and hence will affect the quality of diagnostic services that can be provided to the pearling industry.
The publication of this material will also act as a reference book for a range of other investigations into pearl oysters, such as, nutritional, husbandry and biology studies. It will ensure that the material gathered during project no 94/79 will be preserved for the future benefit of the pearling industry. Objectives: 1. Develop a comprehensive histological photographic database of the normal and diseased tissue of the pearl oyster Pinctada maxima . 2. Compile a computerised atlas showing the basic anatomy of Pinctada maxima with explanatory text and labelled photographs of normal and diseased tissue. 3. Publish this data in a book and/or compact disk format. Read moreRead less
BCA: Development Of Generic Contingency Plans For Disease Emergencies Of Aquatic Animals
Funder
Fisheries Research and Development Corporation
Summary
Development of contingency plans for significant aquatic animal diseases is a critical first step in the management of disease outbreaks. In this respect, aquatic animal health policy development is lagging behind terrestrial animal health policy by approximately 20 years.
At the Melbourne workshops, all sectors of the fishing industry strongly supported the need for a national approach to aquatic animal disease control issues and identified the writing of contingency plans for disease ....Development of contingency plans for significant aquatic animal diseases is a critical first step in the management of disease outbreaks. In this respect, aquatic animal health policy development is lagging behind terrestrial animal health policy by approximately 20 years.
At the Melbourne workshops, all sectors of the fishing industry strongly supported the need for a national approach to aquatic animal disease control issues and identified the writing of contingency plans for disease incursions to be an important task. Also they noted there was a need to build on the unanimous support for this contingency planning process and there was an expectation that some generic, sectoral plans could be developed very rapidly. Objectives: 1. Write four generic (enclosed water; open freshwater; net/open culture marine; open marine) contingency planning manuals for the occurence of significant diseases in aquatic animals to draft form. 2. Following consultation with industry, State government and Commonwealth government representatives, produce four final generic contingency planning manuals. Read moreRead less
Aquatic Animal Health Subprogram: Development Of A DNA Microarray To Identify Markers Of Disease In Pearl Oysters (Pinctada Maxima) And To Assess Overall Oyster Health
Funder
Fisheries Research and Development Corporation
Funding Amount
$157,480.00
Summary
In October 2006, unexplained high mortalities of Pinctada maxima oysters were reported. The disease associated with these mortalities has been termed Oyster Oedema Disease (OOD). It is likely that OOD is caused by an infectious agent and it is possible to cross-infect oysters with infected tissue. The disease spread rapidly and there are no known control measures, no knowledge of a causative agent, no understanding of how widespread the disease was, and no way to test for it. This proposal seeks ....In October 2006, unexplained high mortalities of Pinctada maxima oysters were reported. The disease associated with these mortalities has been termed Oyster Oedema Disease (OOD). It is likely that OOD is caused by an infectious agent and it is possible to cross-infect oysters with infected tissue. The disease spread rapidly and there are no known control measures, no knowledge of a causative agent, no understanding of how widespread the disease was, and no way to test for it. This proposal seeks to develop DNA microarray technology to detect abnormal levels of stress response genes in pearl oysters. These genes will be used as markers in new, rapid diagnostic tests for diseased pearl oysters. The requirement for such rapid diagnostic tests for the detection of OOD is well acknowledged. The spread of the disease could have been limited had there been a test available to differentiate sick animals from healthy ones. Such assays also have applications in routine translocation testing and the assessment of general oyster health. Translocation samples are treated as high priority and current methods report results after several days. With rapid tests derived from DNA microarray analysis it may be possible to report results within 24 hours. The attraction of molecular stress-response markers is that their expression levels change dramatically during times of stress. This can act as an indicator of disease susceptibility. A DNA microarray to target such stress markers in P. maxima could also be used to investigate disease in other shellfish and it will be able to detect effects of other pathogens in addition to those involved in OOD. Our main goal is to use the P. maxima microarray to identify key stress-response genes that can be used to develop a new generation of rapid, inexpensive tests of environmental stress, infection and overall oyster health.
Objectives: 1. To construct a cDNA library using healthy, stressed and OOD-affected oysters. We will use oysters exposed to a range of environmental conditions to make sure that a broad array of stress-response genes are represented in the cDNA library. Cloned cDNAs will be analyzed by PCR to confirm that a broad range of different sized cDNA is also included in the library. 2. To design and print DNA microarray slides for the analysis of diseased states in pearl oysters (P. maxima). cDNA clones to print will be based on sequence analysis. cDNA's will be printed onto the slides in duplicate or triplicate to increase the statistical robustness of subsequent analyses. 3. To use the DNA microarray to identify molecular markers that differentiate pearl oysters that are diseased (including OOD-affected oysters) from those that appear to be healthy. 4. To use the DNA microarray to test for markers of adverse health in pearl oysters that appear to be affected by environmental stressors other than OOD. This will be done using archived samples and oysters that do not fit the case definition for OOD. Read moreRead less
Development Of Generic Contingency Plans For Disease Emergencies Of Aquatic Animals
Funder
Fisheries Research and Development Corporation
Funding Amount
$43,325.82
Summary
Development of contingency plans for significant aquatic animal diseases is a critical first step in the management of disease outbreaks. In this respect, aquatic animal health policy development is lagging behind terrestrial animal health policy by approximately 20 years.
At the Melbourne workshops, all sectors of the fishing industry strongly supported the need for a national approach to aquatic animal disease control issues and identified the writing of contingency plans for disease ....Development of contingency plans for significant aquatic animal diseases is a critical first step in the management of disease outbreaks. In this respect, aquatic animal health policy development is lagging behind terrestrial animal health policy by approximately 20 years.
At the Melbourne workshops, all sectors of the fishing industry strongly supported the need for a national approach to aquatic animal disease control issues and identified the writing of contingency plans for disease incursions to be an important task. Also they noted there was a need to build on the unanimous support for this contingency planning process and there was an expectation that some generic, sectoral plans could be developed very rapidly. Objectives: 1. Write four generic (enclosed water; open freshwater; net/open culture marine; open marine) contingency planning manuals for the occurence of significant diseases in aquatic animals to draft form. 2. Following consultation with industry, State government and Commonwealth government representatives, produce four final generic contingency planning manuals. Read moreRead less
Risk Analysis To Identify And Minimise Biosecurity Risks Arising From Recycling Bivalve Mollusc Shell Waste During Shellfish Reef Restoration Projects In Australia
Funder
Fisheries Research and Development Corporation
Funding Amount
$59,750.00
Summary
Attempts to restore lost shellfish reefs in Australian estuaries using recycled bivalve shells as reef cultch to attract wild oyster settlement are gaining momentum nationwide, with several pilot scale projects being undertaken in Victoria, South Australia, Western Australia, Queensland. and soon in New South Wales. Yet at this time there has been no thorough risk analysis of the biosecurity risks involved or determination of best practice biosecurity principles that should be enacted with each ....Attempts to restore lost shellfish reefs in Australian estuaries using recycled bivalve shells as reef cultch to attract wild oyster settlement are gaining momentum nationwide, with several pilot scale projects being undertaken in Victoria, South Australia, Western Australia, Queensland. and soon in New South Wales. Yet at this time there has been no thorough risk analysis of the biosecurity risks involved or determination of best practice biosecurity principles that should be enacted with each recycled bivalve shell commodity in order to protect existing fisheries and aquaculture industries from translocation of pests and diseases into new areas. Because the bivalve shells used for shellfish reef restoration have been recycled through the retail seafood processing and restaurant chains, they can be originally sourced from a wide range of areas throughout Australia (and potentially even overseas in the case of mussel shells (e.g. green lipped mussels from New Zealand) or cockles, e.g. those imported from SE Asia). The scope of this project will, however, be limited to evaluating the presently undetermined risks of dissemination of pests on the outside of oyster shells (e.g. seaweeds like Undaria, Caulerpa taxifolia, fan worms Sabella spallanzanii , sea squirts Cliona intestinalis etc. ) and endemic diseases (e.g. agents of POMS, QX disease, etc.) that may occur as viable microorganisms within remnant oyster tissues inside the shells of Australian native bivalves. This is because evaluation of the exotic biosecurity risks posed by imported commodities is a separate (although equally urgent) matter that should be determined by Australia's Federal Government authorities via import risk analysis. This project aims to fulfill an urgent need by undertaking a risk analysis that identifies the potential biosecurity hazards (pests and diseases) that could be introduced through recycling of domestically sourced native bivalve shells and will determine the relevant sanitising (risk mitigation) methods required to reduce the risk of introduction of each pest and disease of concern to an acceptable level (i.e. negligible risk).
Objectives: 1. Conduct a literature review of biosecurity risks associated with the use of mollusc shell waste in shellfish reef restoration projects. 2. In conjunction with State and Federal biosecurity authorities and stakeholders, identify hazards (pests and diseases) likely to be associated with recycled bivalve shells in Australia and determine the various risk mitigation methods currently being used in each state jurisdiction. 3. Use risk analysis to identify pest and disease threats and improve knowledge about best practice methods for preventing spread of significant pests and disease agents via shellfish reef restoration projects, leading to enhanced biosecurity management and reduced risk of disease spread into wild and cultured populations of shellfish. 4. Enhance preparedness and capability to prevent spread of aquatic animal pests and diseases of significance to Australia. Read moreRead less