Brown mushroom stem powder shows gut health potential in chicks

Brown mushroom stem powder is getting a closer look as a poultry feed ingredient, with a new Animals paper reporting that the by-product modulated ileal morphology and barrier-related gene expression in layer chicks. The study adds mechanistic detail to a broader Prairie View A&M-led research effort examining whether mushroom stems, often discarded during processing, can serve as a sustainable functional ingredient in poultry diets. (digitalcommons.pvamu.edu)

The backdrop is familiar to poultry nutrition and veterinary teams: soybean meal remains a standard protein source, but cost volatility and sustainability concerns keep pressure on the industry to find alternatives. In the related Frontiers study from the same research program, investigators framed brown mushroom stem powder as a low-cost, underused by-product from Agaricus bisporus processing that could fit circular agriculture goals while partially replacing soybean meal. That study also noted that mushroom stems account for a portion of the harvested mushroom that is often discarded despite containing protein, fiber, vitamins, minerals, and bioactive compounds. (frontiersin.org)

In the layer chick work, researchers used 160 one-day-old Lohmann LSL Lite chicks and later assigned them to four diets containing 0%, 2%, 4%, or 6% brown mushroom stem powder as a partial soybean meal substitute, with five replicates of eight chicks per treatment over 36 days. The brown mushroom stems were sourced from Monterey Mushrooms in Texas, freeze-dried, ground, and formulated into isonitrogenous, isocaloric diets. While the Animals paper focused on ileal morphology and barrier-related gene expression, the companion Frontiers paper from the same line of research found that brown mushroom stem powder maintained growth performance and organ weights overall, while improving selected blood biochemical markers and reducing measured carbon dioxide, ammonia, and methane emissions over a short observation window. (frontiersin.org)

That broader research program also helps explain why the brown stem material, rather than white mushroom stem powder, appears to be drawing more attention. A 2025 Prairie View A&M thesis describing four experiments in layers, broilers, and laying hens said brown mushroom stem powder was selected for further testing after early layer chick comparisons. Across the program, the author concluded that mushroom stem powder did not fully replace soybean meal across all poultry categories, but showed more promise as a health-promoting or functional additive, with reported benefits including improved blood markers, nutrient digestibility, lower greenhouse gas emissions in chicks, and better egg production and egg quality traits in laying hens. (digitalcommons.pvamu.edu)

Industry and academic interest in mushroom-derived feed inputs is broader than this single paper. A recent review in Poultry Science, listed by Prairie View A&M among faculty publications, focused on mushrooms in poultry nutrition, while other reviews have described mushroom stems and spent mushroom substrate as candidates to support gut health, immune function, and productivity. At the same time, the literature is mixed: outcomes depend on mushroom species, whether the ingredient is a stem, whole mushroom, or spent substrate, the inclusion rate, and whether the material is fermented or otherwise processed. (pvamu.edu)

Why it matters: For veterinary professionals, the value of this study is in the gut-health signal. Changes in villus and crypt architecture, along with shifts in barrier-related gene expression, can point to better epithelial integrity and nutrient handling before changes show up in flock-level performance. That matters because subclinical intestinal stress is costly even when birds continue to gain or lay normally. If mushroom stem powder can reliably support barrier function, it may become part of a broader nutrition strategy aimed at resilience, especially in systems trying to reduce feed costs, improve sustainability metrics, or move away from inputs viewed mainly as commodity protein replacers. Still, the current evidence is early and should be interpreted as supportive, not practice-changing, until commercial validation is available. (frontiersin.org)

There are also practical questions veterinarians will want answered before recommending use at scale. The same Prairie View A&M-associated work suggests safety and tolerance were acceptable in the tested birds, but one related study observed a linear increase in heart weight that the authors said remained within physiologic norms and warranted further histopathology and gene-expression follow-up. That kind of detail reinforces the need for dose optimization, consistency in ingredient sourcing, and more field data before broad adoption. (frontiersin.org)

What to watch: Expect the next phase of research to focus on commercial-scale validation, longer feeding periods, egg-phase outcomes, and whether gut-level improvements translate into measurable gains in health, productivity, or antimicrobial stewardship goals. (frontiersin.org)