At what level of heat index can horses generally work comfortably?

When considering the heat index levels for horse work, it's essential to understand how humidity and temperature interact to affect equine performance. The heat index combines these two factors to determine how hot it feels outside, which is crucial for assessing the environment's impact on horses.

A heat index of 125 is generally regarded as the maximum level at which horses can work comfortably. At this index, the combination of temperature and humidity can lead to increased risk of heat stress in horses, but many can still perform light exercises with appropriate care and precautions, such as hydration, breaks, and monitoring for signs of overheating.

Higher indexes, such as 140 and above, pose significant risks for working horses due to the potential for heat-related illnesses. Horses may become fatigued more quickly, their ability to cool down is compromised, and they can experience heat stress or heatstroke. Therefore, working horses under these conditions is not advisable.

Thus, the choice of 125 reflects a threshold where horses might still be able to work with appropriate precautions, while maintaining awareness of the signs of heat stress to ensure their well-being.