Global Aquaculture: Growth, Limitations and Research
Aquaculture is the fastest growing food production sector and contributes significantly to global food security and poverty reduction. Demand for fish in Asia and Africa is on the increase indicating that aquaculture will continue to expand in these regions. In Bangladesh and India shrimp culture sustains the livelihoods of hundreds of thousands of people. Finfish culture too is fundamental to the lives of small-scale farmers in India and in developing countries around the world, including Bangladesh and Malawi. Disease is the biggest single factor limiting growth in aquaculture with associated annual losses estimated at >$6bn globally. Thus, combating disease is critical for both the protection of the livelihoods of farmers and for achieving national and global targets for aquaculture growth in support of poverty alleviation.
Many pathogens are endemic in aquaculture systems but cause disease only under certain conditions. Disease and health status of host organisms is not determined by individual pathogens alone, but by a combination of local environmental and organismal factors including the environmental microbiome, pathogen assemblages, and the pathogen loads in host tissues. Our project seeks to develop and apply molecular biology techniques to identify pond microbiome conditions and biological indicators (‘biomarkers’) associated with health status and disease outbreaks in key crop species (finfish and shrimp) in aquaculture ponds in India, Bangladesh and Malawi. We aim to identify pond microbiomes that signal for an impending disease outbreak. Furthermore, we will determine how the microbiome relates to a variety of pond features, including the use of probiotic treatments currently applied by farmers to improve crop health and increase yield. Models will then be developed using these data and applied to predict the drivers of disease outbreaks.
We will use this information to develop simple, but accurate, molecular assays for use by farmers on individually-owned farms, enabling them to pre-empt and avoid the impacts of disease events by intervention methods triggered by monitoring carried out on-site. Development of an inexpensive but accurate early-warning measurement of pond/crop health status will demonstrate proof-of-concept for a set of tools/methods that can be applied more widely and further developed by industry investment.