Study tests black soldier fly meal as soybean replacement in broilers

Black soldier fly larvae meal is getting another look as a soybean meal substitute in broiler diets, with a newly published Veterinary Sciences study testing replacement rates up to 60% and examining not just growth, but carcass traits, meat quality, and blood biochemistry. The work, published in March 2026 by researchers at Prairie View A&M University and collaborators, reflects the broader push to find lower-impact protein sources for poultry without compromising flock performance or health. (mdpi.com)

That question has been building for several years. Soybean meal remains a core protein source in poultry diets, but price volatility, land-use concerns, and supply-chain pressure have intensified interest in alternatives. Black soldier fly larvae have emerged as one of the leading candidates because of their favorable amino acid profile, high fat content, and potential role in circular agriculture systems that convert organic byproducts into feed ingredients. Prior broiler studies have shown that partial replacement can maintain performance, but results have varied widely depending on whether the product was full-fat or defatted, how diets were balanced for energy and digestibility, and how far soybean replacement was pushed. Supporting that point, an earlier Animals study in 1,750 Ross 308 broilers found that low inclusion of full-fat Hermetia illucens or Tenebrio molitor meal at 2% or 4% did not affect growth, feed intake, feed conversion, or mortality, and actually increased breast yield versus controls, although some treatment-specific changes appeared in meat quality, serum cholesterol fractions, and ileal morphology. (pubmed.ncbi.nlm.nih.gov)

In the new study, 160 ten-day-old Ross 708 chicks were assigned to one of four diets with 0%, 20%, 40%, or 60% black soldier fly larvae meal replacing soybean meal on a 100% equivalent basis. The researchers tracked starter and grower-finisher performance through 42 days, along with carcass traits, meat quality, and blood biochemical responses. While the full paper’s detailed tables were not directly accessible in the search tool, the article description makes clear that the study was designed to test whether black soldier fly larvae meal could serve as a practical substitute for soybean meal across production and health measures, not just weight gain alone. (mdpi.com)

That broader framing matters because the surrounding literature is mixed. One earlier broiler study indexed in PubMed reported effects of partial or complete soybean meal replacement on growth performance and gut metabolites, while another MDPI paper found that complete replacement with defatted black soldier fly larvae meal reduced growth performance, likely because of lower available energy and nutrient digestibility. Other recent work in slow-growing broilers and specialty systems suggests insect ingredients can support acceptable carcass outcomes and may align with sustainability goals, but not every product behaves the same nutritionally. There is also a reminder here that changing soybean meal levels alone can have biological consequences: in one Animals study, a 10% reduction in soybean meal increased mortality and feed intake during the later growth phase, reduced ether extract availability, and shifted cecal microbiota toward higher Campylobacterota and Helicobacter abundance, with raffinose only partly modulating those effects. (pubmed.ncbi.nlm.nih.gov)

Industry and regulatory context is also shifting. In the U.S., AAFCO’s 2025 Official Publication includes a definition for dried black soldier fly larvae for use in finfish, poultry, and swine feed, a notable expansion beyond earlier, narrower use cases. In Europe, the Commission authorized certain processed animal proteins, including insect-derived proteins, for non-ruminant species such as poultry and pigs in 2021, and industry groups have pointed to that change as a major opening for insect-protein commercialization. That doesn’t settle every practical question, but it does reduce one barrier to adoption. The commercial interest is not limited to poultry: recent piglet work found that live Tenebrio molitor larvae improved early feed efficiency, growth, and health indicators after weaning, and helped support performance even under moderately reduced crude-protein diets, underscoring the broader interest in insects as functional feed ingredients rather than simple protein swaps. (aafco.org)

Why it matters: For veterinarians working with poultry operations, this is less about novelty than risk management. Alternative proteins can affect feed conversion, litter quality, gut health, carcass composition, and even meat fatty acid profiles. Reviews and related studies suggest black soldier fly ingredients may offer functional benefits, including possible microbiota effects and reduced dependence on conventional soybean inputs, but they also raise formulation questions tied to chitin content, saturated fat levels, substrate consistency, and mineral balance. In other words, insect meal may be viable, but it’s unlikely to be a plug-and-play swap across all broiler programs. And the broader feed-additive literature reinforces that point: dietary interventions can shift meat-quality traits in useful or unintended ways, as seen with low-level insect meal inclusion affecting breast pH, cooking loss, thigh lipid deposition, and serum lipid fractions, and with phytogenic additives such as stevia extract altering multiple meat-quality parameters in yellow-feathered broilers. (animalmicrobiome.biomedcentral.com)

For veterinary professionals advising integrators or feed programs, the key takeaway is that inclusion rate and ingredient characterization still matter more than the headline concept. A study showing tolerance at one replacement level or with one black soldier fly product doesn’t automatically generalize to another. The commercial value will depend on consistent nutrient specs, cost competitiveness versus soybean meal, and whether health or performance advantages hold up outside controlled trials. Evidence from other species points in the same direction: in grey mullet, black soldier fly meal preserved growth across diets, but the highest inclusion level worsened intestinal condition, while a lower level appeared optimal for gut morphology and innate immune stimulation. (mdpi.com)

What to watch: The next wave of evidence will likely focus on standardizing black soldier fly meal quality, defining optimal replacement ceilings in commercial broilers, and clarifying whether health-related effects, including microbiota and metabolic changes, translate into measurable production or welfare gains at scale. Just as important will be identifying threshold effects early, since both poultry and aquaculture studies increasingly suggest that moderate inclusion may be workable while higher levels can introduce digestibility, gut-health, or product-quality tradeoffs. (animalmicrobiome.biomedcentral.com)