Black Soldier Fly Larvae as a Tool for Managing Animal Waste and Providing a Food Source for the Aquaculture Industry

View the project final report

• 2007 annual report
• 2008 annual report

Commodities

• Animals: fish
• Animal Products: dairy

Practices

• Animal Production: feed/forage, manure management
• Education and Training: demonstration, extension, farmer to farmer
• Farm Business Management: value added
• Production Systems: holistic management
• Sustainable Communities: sustainability measures

This project adapts to Idaho a successful (SARE-funded) research approach to mitigating two growing concerns: • management of animal waste, and • the increasingly costly exploitation of wild-caught fish for fish-based diets used in aquaculture industries. Specifically, this project adapts a biological technique utilizing black soldier fly Hermetia illucens (L.) larvae to convert manure and other animal waste into a food source for rainbow trout (Oncorhynchus mykiss). This bioconversion system was developed in the southern U.S. to reduce manure and control house fly populations in swine and poultry facilities. The system produces large quantities of fly prepupae, suitable as animal-grade foodstuff for fish. These prepupae will partially replace fishmeal and fish oil in trout test diets. Also, Idaho’s aquaculture and major dairy operations are in close proximity, facilitating using the prepupae as an alternate source of protein and oil for trout. Both industries will realize environmental quality, economic, and efficiency benefits: • the aquaculture industry will have a less-expensive and locally produced renewable resource for diets, which will make them less dependent on wild fish populations, and • the dairy industry will reduce manure and related air and water quality concerns, and produce a marketable by-product (prepupae). The project involves researchers from several universities, the extension service staff at University of Idaho, and the aquaculture and dairy industries. Over two-years, investigators will design artificial larvae habitat and evaluate the use of prepupae in trout diets. Data will be incorporated into outreach programs for dairy and fish farmers.

Objectives:
1) Determine, using a 20-week feed trial in rainbow trout: a) whether the feed conversion ratio (weight of feed fed / weight gain) of fish fed omega fatty acid enhanced prepupae and cow manure fed prepupae at 25% and 50% fishmeal replacement are equal to or better than the commercial control diet, and b) the optimal inclusion level for prepupae in rainbow trout diets (i.e. 25% or 50% fish meal replacement) to achieve a feed conversion ratio that is equal or better than the a commercial diet.
2) Determine (and demonstrate on a small scale) at least one method of adapting proven techniques of raising larvae to cold-weather climates (e.g., Idaho) and to cow manure.
3) Develop and provide a cost-benefit analysis to each of the industries participating in the project: One for using black soldier fly larvae for manure reduction on diaries in Idaho, and another for using black soldier fly prepupae as a partial replacement for fishmeal and fish oil in rainbow trout diets.
4) After the successful completion of objectives 1, 2, and 3, identify rainbow trout producers, feed manufacture(s), a maggot producer, and dairy producers in Idaho to plan and design a commercial pilot-scale demonstration project. By the end of the project, the target is to have all industry partners in place for seeking and obtaining the necessary funds for such a pilot commercial project.