Study adds support for black soldier fly meal in broiler diets

A newly published study in Veterinary Sciences adds fresh evidence that black soldier fly larvae meal could replace a meaningful share of soybean meal in broiler diets without obvious harm to performance or health status. In the trial, researchers evaluated 160 Ross 708 chicks assigned to diets in which soybean meal was replaced by black soldier fly larvae meal at 0%, 20%, 40%, or 60%, then assessed growth, carcass traits, meat quality, and blood biochemistry through 42 days of age. (mdpi.com)

The work lands into a long-running search for alternatives to soybean meal, which remains a cornerstone of poultry nutrition but carries cost, supply-chain, and sustainability pressures. Black soldier fly ingredients have attracted interest because they can convert feed-grade byproducts into protein and fat, and because insects are already part of birds’ natural feeding ecology. Still, the science has been mixed on how far formulators can push replacement rates before digestibility, gut structure, sensory quality, or feed conversion begin to shift. (mdpi.com)

In this new study, the headline is not that black soldier fly larvae meal dramatically outperformed soybean meal, but that substantial substitution appeared feasible within the measured endpoints. That matters because earlier broiler studies have pointed to a narrower margin for success. A 2022 MDPI paper on complete replacement of soybean meal with defatted black soldier fly meal suggested full substitution could work in well-balanced diets, while other literature has warned that performance may slip once replacement rises above roughly one-quarter to one-half of soybean meal, depending on formulation and insect meal characteristics. A 2023 paper in the Journal of Insects as Food and Feed similarly examined soybean meal replacement in broilers, underscoring that gastrointestinal and meat-quality effects deserve as much attention as simple bodyweight outcomes. (mdpi.com)

Other broiler data also support a nuanced reading rather than a simple “insects work” conclusion. In an Animals study using full-fat insect meals at relatively low inclusion levels, 1,750 Ross 308 broilers fed 2% or 4% Hermetia illucens or Tenebrio molitor maintained growth performance, feed intake, feed conversion, and mortality comparable to controls. But the diets were not biologically identical in every respect: insect-fed birds had higher breast yield, H. illucens at 4% was associated with lower breast pH and greater cooking loss, thigh fat deposition rose with dose, T. molitor increased total and HDL cholesterol without affecting LDL, and mealworm-fed birds had shorter ileal length. In other words, low-level inclusion looked safe, but species and dose still influenced carcass, meat, lipid, and gut endpoints in ways clinicians and nutritionists may care about.

The wider evidence base also helps frame the caveats. In a broiler study published in the Journal of Animal Science and Biotechnology, partially defatted black soldier fly meal did not appear to disrupt core blood health indicators, but the highest inclusion group showed intestinal changes such as shorter villi, deeper crypts, and reduced villus-height-to-crypt-depth ratio, findings that can signal less favorable gut development. The authors there suggested chitin and nutrient digestibility may be part of the explanation. That’s consistent with the broader industry view that “black soldier fly meal” is not a single uniform ingredient: nutritional value can vary with larval substrate, defatting, processing, and amino acid correction. (jasbsci.biomedcentral.com)

There is also a useful reminder here that lowering soybean meal itself can have consequences if the replacement strategy is not well supported. In an Animals study of low-soybean-meal broiler diets, a 10% reduction in soybean meal increased mortality and feed intake during days 22–42, reduced ether extract availability, and altered cecal microbiota, including higher relative abundance of Campylobacterota and Helicobacter. Adding graded raffinose partly modulated some of those shifts and tended to reduce mortality, but also reduced gross energy and dry matter utilization while downregulating a duodenal glucose transporter gene. The practical takeaway is that soy reduction is not automatically beneficial or neutral; the biology depends on what replaces it and how the whole diet is balanced.

Industry and scientific commentary has generally taken a cautiously constructive tone. The Poultry Science Association’s interpretive summary of related black soldier fly oil research noted that insect-derived ingredients may support comparable broiler performance and even some gut-health or immune endpoints, but emphasized an important practical constraint for North American users: substrate and regulatory compliance matter. In the U.S., AAFCO records show dried black soldier fly larvae raised on feed-grade materials progressed through the ingredient-definition process for poultry feed, and later AAFCO agenda materials reflected movement toward official status. That doesn’t settle commercial adoption, but it does reduce one of the structural barriers that historically kept insect ingredients in the experimental lane. (poultryscience.org)

The interest in insects is also no longer confined to broilers. A recent Frontiers in Veterinary Science study in post-weaning piglets found that daily live Tenebrio molitor larvae supplementation improved early feed efficiency and growth, lowered diarrhea and respiratory problems, and increased vitality scores, with piglets on a moderately reduced-protein diet performing comparably to controls on standard protein. No differences were seen in digestibility or serum metabolic and antioxidant markers at day 42. That does not directly answer broiler formulation questions, but it strengthens the broader case that insect-based ingredients may offer functional feeding effects beyond crude protein replacement alone.

At the same time, alternative feed additives are competing for attention on meat-quality grounds. For example, an Animals study in yellow-feathered broilers reported that dietary Stevia rebaudiana extract altered several meat-quality-related measures, including sensory, physicochemical, amino acid, fatty acid, and storage-associated traits. That line of work is separate from insect protein research, but it underscores how feed innovation in poultry is increasingly being judged not just on growth, but on downstream product quality and shelf-life characteristics as well.

Why it matters: For veterinarians serving poultry operations, this is less a story about replacing soy tomorrow than about how feed risk is changing. If insect meal becomes more available, veterinary teams may increasingly be asked to weigh in on flock response, litter quality, gut health, blood chemistry, carcass outcomes, and any unintended consequences tied to ingredient shifts. The opportunity is clear: a potentially more diversified protein basket. The challenge is that success will likely depend on precise formulation, quality assurance, and realistic inclusion rates, not just ingredient novelty. (mdpi.com)

The regulatory and market context will shape how fast that transition happens. AAFCO documentation from 2024 and 2025 indicates growing acceptance of black soldier fly-derived ingredients in animal feed definitions, including poultry applications for dried larvae raised on feed-grade materials. At the same time, economics, supply consistency, and customer acceptance will still determine whether broiler integrators use these products at scale. Research published through 2025 continues to test where insect meal can match soybean meal without compromising growth or meat quality, suggesting the next wave of studies will likely focus on practical inclusion ceilings and commercial conditions rather than proof of concept alone. (aafco.org)

What to watch: Watch for follow-up trials in commercial broiler settings, more data on amino acid balancing, microbiome and gut morphology changes at higher inclusion rates, and clearer state-by-state feed adoption as AAFCO ingredient definitions move from paper into routine formulation practice. (aafco.org)