Seafood CRC: Planning, implementation and commercialisation of the Australian prawn farming industries five year R&D Plan
Australia's prawn farmers have developed a five year R&D plan through rigorous consultation throughout the industry and with other stakeholders, such as R&D providers and funding agencies.
As a result Australian prawn farmers have identified their primary objective from investment in R&D is achieveing growth in an economic and environmentally sustainable manner.
They aim to do this by investing to increase the industries average production from 4t/ha to 8t/ha, increasing the farm gate value of farmed prawns from $14/kg to $16.50/kg whilst continuosly improving environmental management.
The R&D required to underpin achievement of these objectives has been broken down into three programs:
1. Improving domesticated broodstock
2. Improving prawn farm productivity
3. Improving farmed prawn market value
As such industry support for project development is based on both proposed new projects and existing projects contributing to achieveing these objectives.
Within the Seafood CRC industry involvement in project planning and review is considered a must, as is maintenance of the relevance of the R&D strategy. The Executive Officer position will be responsible for achieving this under the direction of the APFA Executive Committee.
Seafood CRC- Quality, shelf-life and value-adding of Australian oysters (operating expenses)
This project will contribute to work that will fulfil critical CRC Milestones. Furthermore, there is potential that the work
will result in a direct increase in the value of Australian oyster production by value adding existing
products.
The Australian Seafood CRC has previously identified that building capacity in the area of seafood
processing is a high priority for the CRC. This project will make use of and contribute to the collaborative
links with the UK based Grimsby Institute.
The project will develop Australian capability and capacity in value adding of products that will be
applicable to many areas of the CRC. This will be critical to the Australian seafood processing industry
being able to deliver innovative seafood products which are of high eating quality.
SCRC: PhD : The effect of temperature on reproductive development in maiden and repeat spawning farmed Atlantic Salmon: Understanding the molecular basis for improved egg quality and survival
The economic viability of sea cage farming of Atlantic salmon is strongly influenced by the cost of
production of smolts. Understanding the mechanisms that contribute to, or cause reproductive failure in
spawning fish is an essential component of reducing those industry production costs, and at a broader
level, ensuring that there are sufficient smolts produced each year to maintain industry production. The
issue has been identified as an industry priority with the stated SALTAS aim of reducing the reliance on
repeat spawning fish for egg production. The potential cost of failing to solve the problem is high. The
survival of eggs to the eyed embryo stage can be as low as 30-50%, compared with 80% for eggs from
best performing fish (SALTAS data). Modelling of this cost gives direct increases in smolt production
costs of $225,000 per annum, but a potential industry shortfall in production terms of $15-20 million per
annum.
The knowledge gained through this research will be applied in a real life context to the Atlantic salmon industry in Australia to overcome a real and immediate industry bottleneck, and provide information to assist in large scale production procedures. It will provide important new information regarding the endocrine regulation of egg quality, information that could be highly relevant to other finfish industries, such as tuna and kingfish.
In addition to the direct benefit of this research to the Salmon industry, the investigation of the impact of temperature on reproductive process in fish is relevant to environmental studies concerning the impact of global warming on biological processes, with the Atlantic salmon being an example of a fish that has been translocated from a colder environment (Europe) to the warmer Tasmania.
Final report
Tasmanian Atlantic Salmon (Salmo salar) broodstock can encounter temperatures above 20°C, which has a marked negative effect on reproductive development. Broodstock management strategies are needed in order to maintain egg quality in the face of thermal challenge either due to seasonal fluctuation or climate change, where temperatures are expected to rise even further. In Tasmania, the Atlantic Salmon industry uses maiden fish for approximately 75 % of egg production due to their smaller size and the lower cost associated with their husbandry relative to repeats. However, maidens appear to be more susceptible than repeat fish to the effects of elevated temperature. The salmon industry's ability to cope with rising temperature is hindered by the lack of understanding of the effects of thermal challenge on the endocrine system, which ultimately determines egg quality.
Therefore the aims of the research were to:
- Determine how temperature influences endocrine function and reproductive development in maiden and repeat spawning female Atlantic Salmon;
- Understand the molecular mechanisms that determine egg quality in broodstock maintained at elevated temperature; and
- Develop management strategies to maintain endocrine function and egg quality under thermally challenging conditions
The research provided evidence that female maiden Atlantic Salmon are more susceptible to the effects of elevated temperature and that thermal impairment of endocrine function occurs at multiple levels of the reproductive axis. Treatment with various hormonal therapies showed mixed results and suggest that it is difficult to overcome the impacts of higher temperature on the reproductive axis using a single hormonal treatment. Hormonal therapies in the future should simultaneously stimulate vitellogenesis and zonagenesis in order to maintain egg quality. It is evident that the method of hormonal delivery is of considerable importance and implantation techniques also warrant further investigation.
Seafood CRC: Helping emerging leaders to develop networks and make more effective use of scientific and community resources, knowledge and skills
The project is needed to assist with networking future leaders from our industry sector at a level that will enhance their ability to deal with issues that the industry constantly faces adn to be confident when new and emerging issues arise.
There are few participants in the wild capture abalone sector and of those who participate, there are fewer still who possess the capacity to take on the role of future leaders and decision makers. As such it is vitally important to engage as many of the current and future industry leaders, from across a broad section of the industry to provide them with an opportunity to network with each other and with people they would not ordinarily associate with. For example the leadership training course consists of potential future leaders from different sectors that probably network and mix with other industry people, researchers and government managers from their own sector, but rarely do they network or mix with people from other sectors to experience a wider variety of issues that others have to deal with.
The 4th National Abalone Convention provides a perfect opportunity to allow members of the wild capture abalone sector and people from other seafood industry sectors to attend and gain an appreciation of the issues being faced, how the fishery is managed and to meet and greet people from different areas of fisheries management.
Seafood CRC: Development of a genetic management and improvement strategy for Australian cultured Barramundi
The Australian barramundi industry (through ABFA) have long appreciated the potential for improving the sustainability and profitability of production through the appropriate implementation of genetic management and improvement of the species. However, previous attempts to develop a coordinated national strategy for this species have not met with success due to a poor understanding of possible models by which a breeding program within the industry can be implemented, the resources required for implementation and the potential benefits that will arise from a successful breeding program. ABFA views the investment in the Seafood CRC as an opportunity to catalyse efforts towards an industry wide approach to the sustainable and economically viable genetic management and improvement strategy for cultured barramundi.
ABFA prepared a TO for the proposed scoping study identifying the following needs and researchable constraints to the development of a barramundi genetic management/improvement strategy:
• lack of a broad, industry wide, understanding of the potential benefits (and risks) associated with genetic management and improvement
• a lack of a clear understanding of the resources (human, economic, infrastructure and genetic) required for the implementation of genetic management and improvement in this species
• gaps in knowledge required for the implementation of genetic improvement including key genetic parameters and economic weights of traits that could be improved.
• limited information on the genetic status of existing hatchery broodstock and thus their potential as founder stocks for genetic breeding programs
• lack of clear guidelines on appropriate genetic improvement strategies
Final report
The aim of this study was to review existing Barramundi-related genetic knowledge to identify relevant research and where the R&D gaps preventing instigation of Barramundi breeding programs presently exist. They identified and prioritised the research and steps that need to be taken to establish a sound program for genetic improvement of Barramundi farmed in Australia. Strengths, weaknesses, opportunities and threats associated with selective breeding were analysed, a risk analysis performed and suggestions for risk management made. Barramundi genetic knowledge and constraints to Barramundi genetic improvement were reviewed. A research and development strategy, linking research topics into larger collaborative projects, was developed to address these issues. Some basic options for selective breeding were modelled and the benefit-costs compared. The models predict that even under these basic options, selective breeding would be profitable and of high benefit to the industry.
The study predicts that the continuously improved seedstock supplied by an industry wide selective breeding program for Australian Barramundi should stimulate expansion, raise profitability and improve international competitiveness of the industry.
Seafood CRC: Commercial production of all-female reproductively sterile triploid Giant Tiger prawns (Penaeus monodon): Assessing their commercial performance in ponds.
The Australian prawn industry needs a mechanism by which to confer genetic protection of seedstock with elite genotypes so that their commercial benefits can be made available to the entire domestic industry through the sale of elite seedstock for on-growing. To-date triploidy is the only available technology that is near commercialisation that provides a high level of genetic protection through reproductive sterility.
Triploidy has the added benefit of resulting in female populations, with females naturally growing larger than males. This attribute should provide further improvements on harvest yield beyond the performance provided from the elite genotypes alone. If this project demonstrates that total harvest yields are substantially improved through stocking triploids as predicted, triploid induction technologies will be of direct benefit to (and can be utilised by) the entire Australian industry as wild spawned females are also larger than males. This provides direct benefits to the industry independent of accessing the elite genotypes being produced by the four largest Australian prawn producers, providing immediate benefits for any Australian farm or hatchery producing seedstock.
Final report
Several Australian companies currently have breeding programs producing domesticated and selective-bred Penaeus monodon lines. The most advanced of these lines have demonstrated high commercial pond performance over several generations. However, there is a risk for the breeding program companies, due to on-sale or on-rearing of their selected postlarvae. To avoid this problem, genetic protection for the selectively bred prawns is required; however, to-date there is no commercial method for fail-proof genetic protection of prawns. Triploid induction is the only methodology that has been trialled experimentally that shows promise of genetic protection in prawns. However, there are limited reports of triploid induction in Black Tiger Prawns and no studies have reared the larvae through to harvest age and conducted rigorous performance measurements for this species.
This project aimed to develop a technique that would be suitable for commercial triploid induction (which gives each individual an extra set of their own chromosomes; a process that occurs sporadically in nature) of whole spawnings of the Giant Tiger Prawn. A methodology was developed to induce whole spawn triploidy with temperature and chemical shocks. However, hatch rates from this system were consistently low. Despite this a chemical induced triploid family with a high induction rate and reasonable larval survival was produced at a commercial hatchery, allowing rigorous tank-based performance assessments to be carried out.
The overall performance of triploids was comparable to other penaeid prawn species with some exceptions. In triploids, survival was lower, and females were significantly larger. Furthermore, there were more males than females with a 1:1.625 sex ratio and reproductive age triploids were unable to produce viable offspring. This demonstrates that triploidy would provide the industry with a method of genetic protection for Black Tiger Prawns, however significant challenges in maintaining high hatch rates, survival rates and induction rates of the triploids when inducing whole spawnings on a commercial scale still remain.
Seafood CRC: increasing seedstock production of domesticated giant tiger prawns (Penaeus monodon) through improved male fertility
Improving domestication of P. monodon is listed as the top R&D target within the APFA five-year plan (2007-2012). Improving fertility is listed as a key strategy for improving domestication.
If domesticated P. monodon broodstock can be produced economically at a commercial scale, Australian prawn farmers will be in a position to significantly improve farm yields and profitability through selective breeding. To date, P. monodon breeding programs have used both green-water pond systems and clear water systems for rearing domesticated broodstock; with the different systems having certain advantages and disadvantages. Developing protocols enabling a pond-rearing phase within the broodstock production cycle has potential to greatly reduce costs of broodstock production, allowing more companies to maintain domesticated lines and increase production of domesticated-selected seedstock throughout the industry.
In 2002, an APFA-lead research consortium carried out a series of FRDC-funded projects to establish a traditional family-based selection program largely using pond-rearing. However, throughout 2006 and 2007, problems with reproductive tract development and fertility of the pond-reared males significantly compromised the domesticated stocks within the program. In two successive generations across two different pond environments, the gonadal development and fertility of the pond-reared males was found compromised. This project aims to determine ‘if’ and ‘how’ a pond-rearing phase can play a role in producing commercially-viable numbers of P. monodon broodstock.
Seedstock production of broodstock reared in clear water systems has also consistently been constrained by low egg fertilisation. However, the effect that male fertility is having on egg fertilisation rates in clear water systems is not known. The proposed project aims to develop reliable means to evaluate male fertility, and practical measure/s of male fertility which can be used by industry. Such objective measures of male fertility will enable male constraints to seedstock production to be identified and overcome.
Final report
Given the rationale that pond systems are likely the most cost-effective system for large-scale production of Giant Tiger Prawn (Penaeus monodon) broodstock, this project aimed to determine whether pond-rearing poses a significant risk for broodstock production.
The gross reproductive development of males reared in low-density broodstock ponds was found comparable to sibling males reared in controlled-environment tanks. Furthermore, none of the environmental 'stressors' and dietary manipulations examined impacted on male reproductive tract development. Thus, within the boundaries of the parameters tested, we can state that rearing of male broodstock in low-density ponds does not pose inherent risks of gross reproductive tract impairment.
The project also focused on developing an objective measure of 'male fertility' that could be used commercially; and which could be employed within a monitoring regime. None of the simpler assays, which have typically been used as 'proxy' measures of male fertility, were found to correlate with egg fertilisation rates. One assay that was tested, evaluated levels of 'activation' of 'matured sperm' exposed to 'egg water' (EW-AR assay) and this activation correlated with egg fertilisation. Therefore, this provides a reliable measure of male fertility. However, whilst providing an objective measure, this assay is not straightforward to implement commercially; and certainly the applications of this measure are likely restricted. Importantly, an overall approach to long-term monitoring of stocks is suggested; this approach incorporating application of simpler spermatophore/sperm assessments and the EW-AR assay at different points throughout broodstock rearing and at stocking of the hatchery.
During the project, a previously undescribed abnormality termed 'hollow sperm syndrome (HSS)' was observed through histology. Whether the presence/prevalence of such abnormal sperm impacts egg fertilisation rates negatively is not yet known; and further research is thus required to establish its commercial importance