Summer places unique demands on horses. While many owners struggle with risks like colic, heat stress and dehydration are the most significant challenges horses face during warmer months and they can develop quickly, sometimes without obvious warning.
Understanding how horses regulate heat, what signs to watch for, and how to support them through hot conditions is essential for maintaining health, comfort and performance throughout summer.
How Horses Regulate Heat
Horses primarily cool themselves through sweating and respiration. As temperatures rise, their bodies work harder to release excess heat, especially during exercise, transport or periods of high humidity.
Unlike humans, horses can lose large volumes of fluid and electrolytes through sweat. If these losses are not adequately replaced, dehydration and heat stress can occur, even when water is available.
What is Heat Stress?
Heat stress occurs when a horse’s body is unable to effectively regulate its internal temperature.
This can be influenced by:
- High temperatures and humidity
- Intense or prolonged exercise
- Limited shade or airflow
- Inadequate hydration
- Electrolyte imbalance
- Poor recovery between workloads
- Physical and mental stress
- Travel / floating
Heat stress doesn’t only affect working or competition horses, paddock horses can also be impacted during prolonged heat events.
Signs of Heat Stress & Dehydration in Horses
Early recognition is key. Signs may include:
- Excessive or reduced sweating
- Rapid or laboured breathing
- Elevated heart rate
- Lethargy or weakness
- Reduced appetite and thirst
- Seeking shade or standing still for long periods
- Poor recovery after exercise
In more serious cases, horses may appear distressed, uncoordinated or unwilling to move.
Why Dehydration is a Major Risk
Dehydration is one of the most common contributors to summer health issues in horses.
When fluid intake does not keep up with losses, dehydration can affect:
- Circulation and cooling ability
- Muscle function
- Gut motility
- Appetite and energy levels
- Overall resilience to stress
Even mild dehydration can increase the risk of digestive disturbances and reduced performance.
Electrolytes: More Than Just Salt
Sweat contains more than water, it carries essential minerals that support nerve, muscle and fluid balance.
During hot weather, horses may lose:
- Sodium
- Potassium
- Chloride
- Magnesium
If these are not replenished appropriately, the horse’s ability to regulate heat and hydration can be compromised. Supporting electrolyte balance is often an important consideration during summer, particularly for horses that sweat heavily or work regularly. You can use a product like Hi Form ElectroPlus.
Practical Summer Management Tips
Simple management strategies can significantly reduce the risk of heat stress:
• Ensure constant access to clean, cool water
• Provide adequate shade and airflow in paddocks and yards
• Adjust workload and exercise timing during extreme heat
• Allow sufficient recovery time after work
• Monitor hydration and sweat response
• Reduce unnecessary stress during hot periods
• Rug management is crucial to ensure your horse is not overheating
Small changes can have a big impact during prolonged warm weather.
TIP: After rinsing your horse off, leave excess water on the coat, don’t scrape it off. Studies show this helps the horse cool down more effectively.
Supporting the Whole Horse
Heat stress doesn’t occur in isolation. It places additional strain on the gut, immune system and nervous system, particularly when combined with other summer challenges such as insects, pasture changes or travel.
Taking a whole-horse approach, considering hydration, nutrition, environment and stress load, is often the most effective way to support horses through summer conditions.
Not Sure if Your Horse is Coping Well with the Heat?
Every horse responds differently to summer conditions based on workload, age, diet, environment and individual sensitivity.
If you’re noticing changes in behaviour, performance or recovery during hot weather, completing our Quick Horse Questionnaire can help identify areas where additional support may be beneficial.
Final Thoughts 🐴
Heat stress and dehydration are not just extreme-weather concerns, they are everyday summer risks that deserve attention. By understanding the signs, supporting hydration and mineral balance, and adjusting management where needed, horse owners can help their horses stay comfortable and resilient through the hotter months.
