Heat Stress Management in Farmed Pigs

Pigs are highly susceptible to heat stress as they cannot sweat effectively. Managing temperature in pig buildings protects welfare and prevents serious health consequences.

Key Facts

Pigs have few sweat glands and rely on panting and wallowing for thermoregulation
Heat stress begins at temperatures above 25 degrees Celsius for finishing pigs
Consequences include reduced feed intake, impaired reproduction, increased mortality, and compromised immunity
Sows are particularly vulnerable to heat stress during gestation and lactation
Wallowing in mud is the most effective natural thermoregulation behavior for pigs
Climate change is increasing the frequency and severity of heat events for housed pigs globally

Welfare Considerations

Heat-stressed pigs experience genuine physiological and psychological distress. Panting to dissipate heat is energetically costly and competes with normal behavior and feeding. Severe heat stress causes respiratory alkalosis, cardiovascular strain, and can be fatal. Indoor pigs without cooling systems suffer disproportionately during heat events as buildings trap heat. Effective welfare measures include evaporative cooling systems, increased ventilation, drip coolers over lying areas, and access to water for wallowing or bathing. Reducing stocking density during heat events and providing cooler feeding schedules (early morning, late evening) reduces welfare burden.

What You Can Do

Ensure pig buildings have adequate ventilation and cooling systems before summer
Provide water for wallowing or drip cooling during heat events
Monitor pigs closely during high-temperature periods for signs of heat stress
Reduce stocking density during heat events if possible
Support welfare standards that require cooling provision in pig buildings