Heat stress causes significant welfare harm and production losses in dairy cattle, but is substantially preventable through shade provision, sprinkler systems, and feed management strategies.
Heat stress causes cattle to experience elevated body temperature, panting, reduced feed intake, and lethargy — a physiologically and psychologically stressful state analogous to severe heat exhaustion in humans. Pregnant cows experiencing heat stress during late gestation produce calves with impaired immune function, reduced birth weight, and compromised future productivity — welfare impacts that extend across generations. The economic cost of heat stress — reduced milk production and reproduction — aligns with the welfare imperative to provide cooling. Sprinkler and fan systems pay for themselves rapidly through production improvements, yet many operations remain without basic cooling infrastructure. As climate change extends and intensifies heat stress seasons, the welfare calculus for cooling provision becomes increasingly compelling.