Understanding Ostreid herpesvirus type 1 risk: alternative hosts and in situ hybridisation
SCRC: RTG: Visit to the laboratory of Professor Douglas Tocher (Institute of Aquaculture, University of Stirling, Scotland) to undertake collaborative research into the lipid and polyunsaturated fatty acid (PUFA) metabolism of Southern Bluefin Tuna
Final report
The purpose of this grant was to undertake collaborative research into the lipid and polyunsaturated fatty acid (PUFA) metabolism of Southern Bluefin Tuna (SBT) using a SBT cell line that was recently produced. This project followed an international trend towards increasing fish oil replacement in feeds for farmed fish to improve the sustainability of the target industry.
Very little is known about dietary fish oil replacement in Bluefin tuna species so the purpose of this research was to obtain data which may be used to predict the impacts of fish oil replacement in future manufactured feeds for farmed SBT. Since it was logistically difficult and expensive to obtain such data from traditional feeding trials with SBT, the approach using the SBT cell lines offered a more rapid and cost-effective alternative.
SCRC: PhD Extension : RNA interference (RNAi) as a means to control Neoparamoeba perurans, the causative agent of amoebic gill disease (AGD). (Student: Paula Lima)
Paula Lima began her PhD within project 2007/750 ‘AGD Vaccine Phase III: Sea-based trials, refinement and commercialisation’. Paula began in 2009 and her full stipend, travel and operating funds were paid out of this project. Paula was adopted into the Seafood CRC in late 2009, with no further financial support for her stipend or operating expenses. In 2010 at a meeting of the project’s Management Advisory Committee (MAC), a decision was made to redirect research as it was apparent that the vaccine was not a commercial reality. This occurred one full year into her PhD. This had an effect on Paula’s PhD which was subsequently changed to investigating the use of RNAi as either a research tool and/or a control strategy for AGD. This meant that the entire 1st year’s work was made redundant and Paula had to effectively ‘start over’. Paula has effectively been working in her new area for almost two years. However, the project which funded her stipend is no longer operating. Therefore, Paula still has effectively one year of her PhD left to run. For this reason we sought support from the Seafood CRC to enable Paula to complete her research. This application has the full support of Adam Main, the CEO of the Tasmanian Salmonid Growers' Association (TSGA).
Final report
RNA interference has emerged as a powerful tool for rapid analysis of gene function in non-model organisms and has the potential to identify candidate targets for interventions against diseases of economic importance to aquaculture. The main purpose of the study was to use functional and comparative genomics approaches to investigate whether the RNAi mechanism has been retained or lost in species from the Neoparamoeba genus.
The results provide strong evidence that both infective and non-infective species from Neoparamoeba spp. have evolutionarily retained key genes involved not only in the canonical RNAi mechanism, but also in the mirNA and PiRNA pathways. Despite being promising, these findings are still preliminary and the reality of applying RNAi technology to develop new treatment strategies against AGD still needs further effort.