Managing Heat Stress in Livestock

Heat stress significantly impacts livestock health, productivity, and welfare. Understanding how different animals respond to heat helps you protect your herd.

Temperature Humidity Index (THI)

The THI combines temperature and humidity to measure heat stress risk:

• Below 70: Comfortable
• 70-74: Mild stress
• 75-78: Moderate stress
• 79-83: Severe stress
• Above 84: Emergency conditions

Cattle Heat Stress

Signs to Watch For

• Increased respiration rate (>80 breaths/minute)
• Open-mouth breathing or panting
• Excessive drooling
• Reduced feed intake
• Decreased milk production
• Bunching together seeking shade
• Standing in water if available

Prevention Measures

• Provide adequate shade (40-60 sq ft per animal)
• Ensure unlimited access to clean, cool water
• Use sprinkler systems for cooling
• Improve air movement with fans in confined areas
• Avoid working cattle during hot periods
• Feed during cooler parts of the day

Horses and Heat

Horses regulate heat differently than cattle and can generate significant body heat during exercise.

Warning Signs

• Profuse sweating or lack of sweating (anhidrosis)
• Rapid, shallow breathing
• Elevated heart rate that doesn't recover
• Muscle tremors
• Stumbling or incoordination

Cooling Strategies

• Apply cool water over entire body
• Scrape water off and reapply
• Position in breeze or use fans
• Offer small amounts of water frequently
• Avoid cold water shock in overheated horses

Sheep and Goats

Wool and hair coats affect heat tolerance:

• Time shearing before peak summer
• Provide shade structures
• Ensure water access at multiple locations
• Consider grazing schedules during cooler hours

Poultry

Birds have no sweat glands and are highly susceptible to heat:

• Maintain adequate ventilation
• Provide cool, clean water
• Consider misting systems
• Remove mortalities promptly

Emergency Response

If an animal shows severe heat stress:

• Move to shade immediately
• Apply cool (not cold) water
• Provide water to drink in small amounts
• Contact veterinarian for severe cases
• Monitor recovery closely