Available online 28 September 2026 in the Journal of Dairy Science, a 13-author research team has published a methods paper introducing a controlled wood smoke exposure model for measuring physiological responses in dairy calves.

Titled "A novel controlled wood smoke exposure model to evaluate physiological responses to smoke-derived air pollution in dairy calves," the study describes an experimental design in which calves are exposed to wood smoke under defined conditions, with researchers tracking physiological endpoints against a controlled baseline. The lead authors are M. Kamyabi, A. Pace, J.R. Kok, A.M.S. Smith, D. Sarantopulos, L. Christensen, A.S. Marquez-Acevedo, L. De Moura Pereira, M. Larson, A. Ahmadzadeh, D. Konetchy, P. Rezamand, and A.L. Skibiel. The breadth of that author list signals cross-disciplinary collaboration spanning animal science, veterinary medicine, and atmospheric or environmental science.

What does the new model measure?

The paper delivers a controlled protocol in which dairy calves receive wood smoke exposure under defined conditions, allowing researchers to quantify physiological responses to smoke-derived air pollution. Standardizing exposure removes much of the variability that has limited earlier field studies of wildfire smoke and confined-animal production.

The work sits within an active research area examining how particulate matter and combustion products affect ruminant respiratory, metabolic, and immune function. Dairy operations in the U.S. Pacific Northwest, Northern California, and other wildfire-exposed regions have flagged production and health concerns in cattle during smoke events, but controlled data remain scarce.

Why a controlled model now?

Annual wildfire smoke days have lengthened across the Western United States and into parts of Canada, Australia, and the Mediterranean basin. Dairy calves represent a particularly sensitive population: developing lungs, an immature immune system, and the air-handling demands of individual housing make them a useful sentinel for subclinical respiratory insults.

A reproducible exposure protocol also addresses a regulatory and research gap. Existing U.S. EPA and OSHA standards target human ambient and occupational exposures, leaving livestock thresholds to extrapolation. A controlled model gives researchers a tool to generate dose-response data in calves directly, rather than borrowing human reference values.

What changes at the farm and the exam table?

For food-animal veterinarians, a validated exposure model offers a path toward evidence-based guidance for producers during wildfire season. The protocol could clarify which physiological markers shift earliest, informing decisions on ventilation, housing, and timing of elective procedures when air quality deteriorates.

For producers, the model lays groundwork for future threshold-based recommendations — analogous to existing temperature-humidity indices for heat stress — that could eventually translate into barn-level management triggers during smoke events. Calf-raisers in smoke-prone regions currently rely on general public-health advisories; calf-specific thresholds are not in routine use.

What are the public-health implications?

Wildfire smoke contains fine particulates (PM2.5) and combustion-derived compounds that affect both animals and the people who work alongside them. A model that links dose and physiological response in calves provides a translational tool for studying similar exposures in agricultural workers, who often share the same air for extended shifts.

Dairy farm employees, many of whom labor outdoors or in minimally filtered barn environments, face documented respiratory and cardiovascular risk during smoke events. Calf-side data, once generated, can support occupational health recommendations for those workers and inform decisions about shift scheduling, respirator use, and barn-side air filtration.

What's next?

The team has framed the paper as a methodological platform rather than a clinical endpoint study. Follow-on research will likely apply the model to specific outcomes: respiratory mechanics, acute-phase proteins, oxidative-stress markers, and longer-term performance in older heifers.

For practitioners and producers seeking immediate clinical guidance, the practical payoff sits downstream. The contribution in this paper is the model itself — a reproducible, controlled system that turns an increasingly common environmental hazard into a measurable variable in dairy research.