HSWRI Project Leaders – Mark Drawbridge and Dave Jirsa
The goal of this research is to develop practical diet formulations for marine finfish that utilize significantly less fish meal and oil from traditional industrial fisheries than contemporary commercial diets.
Although the amount of fish meal and oil in diets of farmed fishes has decreased in recent years through research efforts like ours, aquaculture production as a whole has increased dramatically, so there remains a net increase in demand on traditional fish meal and oil resources. This increasing demand, coupled with natural fluctuations in wild stocks of bait fish, has significantly increased the cost of fish meal and oil in recent years. So, the research described here has significant conservation and economic importance with global relevance.
The search for alternatives to fishmeal in fish diets has been ongoing since the 1970s, beginning with rainbow trout. In the last decade, however, rising fish product prices, intense regulation of nutrients in hatchery effluents, and debate on the sustainability of using fish as an aquafeed ingredient has intensified the need for this research. Soybean meal has been studied extensively as a partial replacement for fishmeal due to its abundance and relative price. Corn products, including gluten meal and whole yellow corn, and terrestrial animal by-products, such as blood, poultry, meat, bone, and feather meals, have also been evaluated due to their relatively low cost and abundance. Aquatic and marine by-products, such as algae and fish processing waste, have been minimally studied but show great promise. Fish oil is in even shorter supply than fishmeal, but alternatives to fish oil can impact feed consumption, growth, or sensory (e.g. palatability) characteristics. So far, blending marine and terrestrial plant source oils and oils produced from seafood processing waste have demonstrated the most promise.
Methods and Results – Laboratory feeding trials comparing different experimental formulations are conducted for 2 months during which time fish performance is monitored. The most successful diets are then tested in longer term growout trials of up to 10 months. Fish performance measures are complimented by analyses of tissue biochemistry to ensure that the healthful attributes of the fillet is maintained. Taste testing by consumer panels is used to confirm that downstream marketability is maintained. Our results indicate that up to 100% of fish protein and fish oil can be replaced by one or more of the alternative ingredients we tested, with cultured fish experiencing equal, if not better, growth as compared to commercial fish-based control diets.
Why does this research matter? – This research is part of our effort to advance sustainable aquaculture practices. By developing viable commercial diets that use alternative ingredients, we help ensure the environmental and economic sustainability of aquaculture worldwide.
Funding and Donation Opportunities – Donor support of $75,000 is needed toward this project annually.
- Trushenski, J., B. Mulligan, D. Jirsa, and M. Drawbridge. 2013. Sparing fish oil with soybean oil in feeds for white seabass: effects of inclusion rate and soybean oil composition. North American Journal of Aquaculture 75:305-315.
- Jirsa, D., G.P. Salze, F.T. Barrows, D.A. Davis, and M. Drawbridge. 2013. First-limiting amino acids in soybean-based diets for white seabass Atractoscion nobilis. Aquaculture 414-415:167-172.
- Jirsa, D., D.A. Davis, F.T. Barrows, L.A. Roy, and M. Drawbridge. 2014. Response of white seabass to practical diets with varying levels of protein. North American Journal of Aquaculture. 76(1):24-27.
- Jirsa, D., D.A. Davis, G.P. Salze, M. Rhodes, and M. Drawbridge. 2014. Taurine requirement for juvenile white seabass (Atractoscion nobilis) fed soy-based diets. Aquaculture 422-423:36-41.
- Trushenski, J., A.N. Rombenso, M. Page, D. Jirsa, and M. Drawbridge. 2014. Traditional and fermented soybean meals as ingredients in feeds for white seabass and yellowtail jack. North American Journal of Aquaculture. 76(4): 312-322.
- Buentello, A., D. Jirsa, F.T. Barrows, and M.A. Drawbridge. Minimizing fishmeal use in juvenile California yellowtail, Seriola lalandi, diets using non-GM soybeans selectively bred for aquafeeds. Aquaculture 435: 403–411.