Converting Dairy Manure into Livestock Feed with Black Soldier Flies

Is it possible to transform manure into cows, chickens, or fish? Researchers at Texas A&M AgriLife are exploring this unique approach within a circular economy framework.

Funded by a $618,000 grant from the US Department of Agriculture National Institute for Food and Agriculture, scientists from the Texas A&M College of Agriculture and Life Science Department of Entomology, in collaboration with Mississippi State University, are conducting a three-year study.

The research aims to investigate the use of black soldier flies in cleaning up dairy manure, with a focus on assessing their potential as an ingredient in livestock, poultry, and aquaculture feed.

The project, led by Jeff Tomberlin, PhD, a Professor and Director of the Center for Environmental Sustainability through Insect Farming, along with Anjel Helms, PhD, an Assistant Professor and chemical ecologist, will address both environmental and economic aspects of converting dairy waste into protein for feed.

Initial data suggests that probiotics may enhance the digestive process in animals, promoting the conversion of waste to insect biomass, reducing greenhouse gas emissions and odors, and mitigating concerns about pathogens in the manure.

Jeff Tomberlin and Anjel Helms will spearhead the study, with Heather Jordan, PhD, an Associate Professor and Microbiologist at Mississippi State University, analyzing the resulting larvae and frass for microbial diversity and feed safety.

The day-to-day data collection will be overseen by Anjel Helms’ Postdoctoral Research Associate, Amber MacInnis, Ph.D., with the assistance of students.

We’re testing the limits of black soldier fly production in conjunction with probiotics to see how efficient they could be for large animal production facilities, in this case dairies. Manure management is an expense to these producers, and we are testing to see if this is a way to manage that waste and turn it into a productive feed source.”

Anjel Helms PhD, Assistant Professor and Chemical Ecologist, Department of Entomology, Texas A&M AgriLife

Turning an expense into a resource

Black soldier fly larvae exhibit an impressive ability to consume their weight in organic waste daily during a two-week span–approximately 1 gram, equivalent to the weight of a single raisin per larva. While this may seem trivial on an individual basis, the cumulative impact becomes significant when considering the millions of black soldier fly larvae involved.

For instance, established facilities across Europe, Asia, and North America can process 100 tons of waste daily by harnessing the waste-digesting capabilities of black soldier fly larvae.

In the experiments conducted by MacInnis, plastic containers holding around 18 pounds of manure are utilized, with 10,000 black soldier fly eggs introduced. The larvae hatch, consume the dairy manure over a two-week period, undergo harvest, and the cycle is then repeated.

A crucial aspect of the project involves assessing the safety of harvested larvae as ingredients for feed. The microbial diversity in larvae that consume manure is not well understood, and this could potentially impact feed safety. While Helms believes that larvae consuming manure are likely safe for livestock consumption, certification of the end product remains essential.

This is an exciting study to be a part of because it is problem-solving at its core. These dairies produce an enormous amount of waste. If black soldier flies can be an efficient part of their management process and provide other benefits, that could be a big breakthrough across the industry.”

Amber MacInnis PhD, Postdoctoral Research Associate, Texas A&M AgriLife

Layers of potential benefits from waste conversion

Black soldier flies play a crucial role in consuming organic waste, including manure; however, there is potential for enhancing the efficiency of the waste conversion process.

The research aims to leverage probiotics to improve the black soldier fly’s ability to convert dairy manure, with a specific goal of removing over 50% of nitrogen and potassium from the waste.

Collaborating with Jordan, the team is investigating the impact of probiotics on this waste conversion process. In addition to reducing reliance on conventional manure management methods such as waste storage lagoons, the conversion of manure by black soldier flies is anticipated to yield environmental benefits.

There is potential for layers of economic and environmental benefits to incorporating black soldier flies in manure management. Turning waste into a resource sounds too good to be true, but we are understanding more and more about the ways black soldier flies can solve a lot of problems.”

Anjel Helms PhD, Assistant Professor and Chemical Ecologist, Department of Entomology, Texas A&M AgriLife