Physiological Adaptations and Thermoregulatory Indicators of Heat Stress in Bovine Production Systems

Abstract

Simple Summary Heat stress is one of the major challenges affecting cattle production worldwide, particularly in tropical and subtropical regions. When environmental temperatures exceed the animal’s capacity to dissipate heat, physiological mechanisms are activated to maintain body temperature, often compromising productivity, reproduction, health, and welfare. Identifying reliable thermoregulatory indicators is therefore essential for early detection and management of heat stress. This communication reviews the principal physiological responses and biomarkers associated with thermal stress in cattle and illustrates their practical application through a field study conducted in Bos indicus cows under tropical conditions in Tabasco, Mexico. Environmental temperatures measured using black globe thermometers were significantly higher under direct solar radiation than under shaded conditions, and increases in ambient heat load were associated with elevated rectal temperatures. These findings highlight the importance of combining environmental and physiological indicators to improve heat stress monitoring and support management strategies aimed at enhancing animal welfare and production efficiency in warm climates.