Get the Fish Out: Black Soldier Fly Larvae and Marine Macro-algae as Feed Ingredient Replacements for Small Land-based Aquaculture Operations

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Commodities

• Animals: fish

Practices

• Animal Production: aquaculture, feed formulation
• Sustainable Communities: food loss and waste recovery/reduction, food loss and waste recovery/reduction

Feed and labor are the largest expenses for aquaculture operations. Labor is a fixed cost, but feed costs can fluctuate wildly with vagaries in the supply chain, shipping (fuel) costs and ingredient costs. Small producers are especially susceptible to the financial risk of high costs and limited availability of effective feed. Concerns about sustainability plague the fish meal-based production of commercial feeds. As more and more small-scale aquaculture and aquaponics operations launch in the Northeast, feed availability and efficacy will be a key factor in the industry’s success. This project seeks to answer whether a feeding regime that reduces fish meal protein can achieve similar growth, filet quality, and economics in rainbow trout compared to a standard commercial feed made from fish-based protein and fish oil. Furthermore, can the economics of small-scale aquaculture be improved by making feed on-site? Building on previous research, we will assess the operational and economic viability and sustainability of fish feeds using black soldier fly larvae, micro and macro-algae, and brewer’s waste in a Maine aquaponic operation. We will track and measure financial inputs, fish health, culinary and nutritional desirability of product, system water quality, and waste production to generate a complete picture of how feed alternatives impact production and business operations. Results will be shared through our partner networks, which touch the aquaculture farming industry, food industry, and the community of consumers.

We will address whether reduced fish protein feed can achieve similar growth, filet quality, and economics for rainbow trout as standard fish protein/ fish oil commercial feed. We will  use an all-alternative feed experimental diet (a), diet with 50% fish meal reduced (b), diet with 25% fish meal reduced (c), commercial fish meal diet (d) to assess differences in feed conversion ratio, digestibility, weight gain, filet quality and Poly-unsaturated fatty acid content (PUFA), as well as the cost in labor and materials to make fish food. We are interested in whether the cost to benefit ratio, including sustainability, of land-based aquaculture (LBA) can be improved by producing feed in-house with light-duty pellet pressing and extrusion machinery.