Researchers at UC Santa Cruz have developed a sustainable aquaculture feed for farmed rainbow trout, replacing traditional fishmeal with a marine microalgae species, Nannochloropsis sp. QH25. Their study found that trout fed with this alternative feed grew at the same rate as those on conventional fishmeal-based diets, maintaining nutritional value and potential cost-effectiveness.
This innovation addresses the seafood industry’s reliance on wild-caught fish for aquaculture feed, which strains ocean ecosystems. While previous attempts failed due to trout’s preference for fish-based flavors, researchers overcame this by adding taurine and lecithin as feeding stimulants and improving processing techniques.
The team now aims to replace fish oil as well, creating a fully fish-free feed that reduces aquaculture’s environmental impact. However, large-scale adoption depends on improving the cost-effectiveness of microalgae production. Future collaborations between the microalgae and aquaculture industries could drive sustainable growth in seafood production.