Study points to 28-day vitamin D glycoside window in broilers

A new Animals paper sharpens the conversation around nutritional prevention of BCO lameness in broilers by focusing on a practical question: how long should 1,25(OH)2D3-glycosides be fed to matter? In the new experiment, researchers found that supplementing feed for 28 days reduced clinical BCO lameness, while a 14-day program did not deliver the same benefit. The study, published under DOI 10.3390/ani16162586, evaluated 840 Cobb 500 chicks in a 56-day trial using an aerosol transmission induction model. (citedrive.com)

That result builds on a growing body of work from the same research group. Earlier studies from the University of Arkansas showed that supplying 1.0 µg/kg of 1,25(OH)2D3-glycosides during the first 28 days cut BCO incidence by roughly 53%, and performed comparably to supplementation across the full 56-day production cycle. By contrast, feeding the product only in the last 28 days was far less effective. Together, those studies point to early-life supplementation, not just total exposure, as the key variable. (scholarworks.uark.edu)

In the new trial, birds were assigned to four groups: a wire-floor positive control on a basal diet, a litter-floor negative control on a basal diet, and two litter-floor treatment groups receiving 1 µg/kg feed of 1,25(OH)2D3-glycosides for either 14 or 28 days. Clinical lameness was assessed daily beginning on day 21, and lame birds underwent necropsy to score BCO lesions. The reported cumulative lameness incidence was 55.5% in the 28-day group, compared with 85.0% in the negative control and 85.5% in the 14-day group; only the 28-day regimen showed a significant reduction. (citedrive.com)

The ingredient studied is a glycosylated form of active vitamin D3 derived from Solanum glaucophyllum, marketed commercially as Panbonis. Industry and academic summaries describe it as a source of 1,25-dihydroxyvitamin D3-glycosides that can support calcium and phosphorus utilization and may also influence immune and barrier function. A 2025 University of Arkansas thesis tied 28-day supplementation to increased expression of tight-junction genes in the gut and, more strongly, the respiratory tract by day 28, offering a possible mechanistic explanation for lower BCO susceptibility. That mechanism remains inferential, but it aligns with current thinking that BCO risk involves bacterial translocation, bloodstream spread, and colonization of stress-damaged leg bones. (herbonis.com)

Industry discussion around BCO has increasingly framed the condition as a multifactorial problem rather than one with a single fix. At the 2024 International Avian Influenza Summit, University of Arkansas researcher Adnan Alrubaye described BCO as affecting 3% to 5% of US broilers, with epidemic cases reaching 20% to 25%, and emphasized that subclinical disease likely represents a much larger burden than visible gait-4 or gait-5 birds. He also argued that prevention will likely require combinations of nutrition, microbiome management, and vaccination, rather than any stand-alone intervention. (thepoultrysite.com)

Why it matters: For veterinarians and technical service teams working with integrators, this study helps narrow a management question with real implementation consequences. If 28 days of early supplementation performs while 14 days does not, nutrition programs may need to be designed around the first month of life, when skeletal growth, mucosal barrier development, and infection pressure may be most consequential. That has implications for feed formulation, cost modeling, and how veterinarians discuss lameness prevention with production managers. It also reinforces that BCO control sits at the intersection of welfare, productivity, and food safety, not just orthopedic health. (citedrive.com)

The study also comes with limits worth noting. The work used an experimental aerosol transmission model rather than a commercial field setting, and the reported lameness rates were high relative to many routine production environments, which may affect generalizability. Even so, the model is established in BCO research and is meant to create consistent disease pressure for comparing interventions. (citedrive.com)

What to watch: The next questions are whether the 28-day window holds up in commercial flocks, whether it combines effectively with probiotics or vaccines, and whether mechanistic work on gut and respiratory tight-junction signaling can translate into practical biomarkers or more targeted prevention programs. (scholarworks.uark.edu)