Black soldier fly larvae show promise as partial soy replacement

Replacing soybean meal with black soldier fly larvae meal at low to moderate levels appears workable in broilers, according to a new study in Veterinary Sciences. In the trial, researchers fed 160 Ross 708 chicks diets in which black soldier fly larvae meal replaced soybean meal at 0%, 20%, 40%, or 60% on an equivalent basis. The authors reported that 20% and 40% replacement maintained growth, nutrient digestibility, physiological measures, and meat quality, while 60% replacement reduced productive performance, suggesting the ceiling may be lower than some sustainability-focused formulations might hope. (mdpi.com)

Why it matters: For veterinary professionals and poultry advisers, the study adds to a growing body of evidence that insect protein can help reduce reliance on soybean meal without clearly compromising bird health, at least at partial inclusion levels. That matters as feed formulators look for alternatives tied to lower land use and less competition with human food systems. But the findings also reinforce a practical caution: higher inclusion rates may create nutritional limitations, potentially linked to chitin, amino acid balance, fat profile, or digestibility, and still require careful formulation rather than one-for-one substitution. That broader point is consistent with other animal nutrition work: one broiler study found low inclusion of full-fat Hermetia illucens or Tenebrio molitor meal (2% to 4%) did not hurt growth, mortality, blood measures, or carcass quality, though some meat-quality and gut-shape changes emerged, while a fish study identified a clearer threshold, with about 10% black soldier fly meal supporting performance and gut health better than higher levels. Separately, work on low-soybean-meal broiler diets suggests simply reducing soybean meal can carry its own costs, including higher mortality and poorer nutrient utilization, underscoring that the real challenge is not just replacing soybean meal, but preserving overall diet function. A recent meta-analysis found black soldier fly inclusion was generally safe in broilers up to about 10% of the diet, and a 2023 systematic review concluded low insect meal inclusion tends to perform similarly to control diets in broilers without intestinal challenge. (publish.csiro.au)

What to watch: Expect follow-up work to focus on where the practical inclusion threshold sits in commercial diets, how processing method changes digestibility, and whether evolving feed rules make broader poultry use easier to scale in the U.S. It will also be worth watching whether future studies can improve palatability, early feed intake, or resilience the way live mealworm supplementation did in post-weaning piglets, where larvae were readily consumed and supported health and performance even under moderately reduced-protein diets. Alongside protein replacement, researchers are also testing other feed additives that may influence final product quality, including phytogenics such as stevia extract in broilers. (aafco.org)