Heat stress is a major and growing welfare problem for cattle globally. Understanding its physiological effects and mitigation strategies is essential for humane livestock management.
Heat stress causes significant suffering in cattle. Panting, drooling, bunching, and inability to eat normally are visible distress indicators. Sustained heat stress causes physiological dysfunction — acidosis from altered feeding patterns, immunosuppression, and in extreme cases, heat stroke and death. The welfare problem is worsening as climate change extends heat stress conditions to higher latitudes and longer seasons. Intensive dairy systems that maintain high milk production levels have the least physiological heat tolerance reserve. The growing scale of heat stress as a welfare problem requires both immediate management interventions and long-term systemic responses to the underlying climate drivers.