Project number: 2006-064
Project Status:
Completed
Budget expenditure: $133,716.60
Principal Investigator: Philip Nicholls
Organisation: Murdoch University
Project start/end date: 21 Sep 2006 - 30 Jun 2009
Contact:
FRDC

Need

One of the key objectives of the WA Department of Fisheries Business Plan is to ensure ecological and environmental sustainability of the pearling industry. The proposed project will be of direct benefit to the Western Australian pearling industry in that it will document the existence, if any, of the Haplosporidium and its effect on Australia’s most important commercial pearl oyster species.

Given the difficulties in detection and identification of Haplosporidium by current techniques (histology and light microscopy), there is a need for alternative, reliable, and cost-effective methods for detecting and speciation of Haplosporidium.

In the context of a pearling industry that is undergoing a process of intensification in which disease management continues as a priority issue, this lack of basic diagnostic capability needs to be addressed.

Such diagnostic tools will help assess the parasite’s impact on the pearl oyster and its potential threat to the industry, as well as providing tools to assist in diagnosis, epidemiology and surveillance of disease. This could be of key importance in trying to determine the true geographic extent of the parasite, to assess why the outbreaks have been sporadic in nature, and to assist in the early detection and management of possible future outbreaks.

In addition, there is an international shortage of pathologists with expertise in molluscan pathology and a national need for research projects that are suitable for the postgraduate training of aquatic animal health specialists.

The FRDC Aquatic Animal Health Subprogram (AAHS) and Scientific Advisory Committee has reviewed the preliminary research proposal and assessed it as high priority.

Objectives

1. To develop a PCR test that is sensitive and specific, being able to detect Haplosporidia generally, yielding a product that is suitable for sequencing and determination of the species.
2. To sequence amplified genomic segments, obtained by PCR, from infected pearl oysters, to determine the species and its phylogenetic relationships.
3. Once sequence data are obtained (from 1), to develop a PCR test that specifically detects only the Haplosporidian species in pearl oysters.
4. To use sequence data obtained in (2), to document the location and distribution of the parasite within the oyster, by the development and application of in situ hybridisation, as part of a study on its life cycle and biology, in conjunction with routine light microscopy. In situ hybridisation is also key in confirming PCR test results.
5. To determine, retrospectively, the molecular identity of the Haplosporidian involved in the previous outbreaks, to see if the same isolate was involved in all outbreaks.
6. To determine whether the parasite is still present in the original outbreak sites and in other sites not historically affected, by the deployment and assessment of spat in these locations.
7. To develop a means for the assessment of infectivity and pathogenicity using rock oysters and their endemic Haplosporidium as a model.

Final report

ISBN: 978-0-86905-989-0
Author: Philip Nicholls

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PROJECT NUMBER • 2011-401
PROJECT STATUS:
COMPLETED

Marine Discovery Centres Australia annual network meeting

1. To enable representatives from Marine Discovery Centres across Australia to meet in different marine regions at an annual workshop to share new ideas, educational resources and materials.
ORGANISATION:
Marine Discovery Centre Maclean
Adoption