Farm Animals

Heat Stress in Dairy Cattle: A Growing Climate Challenge

Rising global temperatures are increasing the incidence and severity of heat stress in dairy cattle, reducing welfare, milk production, and reproductive success.

Key Facts

Dairy cows produce excessive metabolic heat and are especially vulnerable above 22C
Heat stress causes reduced feed intake, lower milk yield, and reproductive failure
Conception rates drop from 65% to under 30% during summer heat stress periods
High-producing Holstein cows are most vulnerable due to their high metabolic rate
Climate models predict significant expansion of heat stress risk zones by 2050

Welfare Considerations

Heat-stressed cows display panting, increased water intake, and reduced lying time as they seek to offload heat. Chronic heat stress causes immunosuppression, mastitis, lameness, and early death. It represents a growing welfare burden that will worsen without proactive management and is already causing silent suffering in millions of animals.

What You Can Do

Support shade, fans, and sprinkler systems as minimum heat abatement standards in dairy regulations
Choose dairy products from regions with strong heat stress management standards
Advocate for livestock housing regulations that include mandatory cooling systems
Support research into heat-tolerant dairy breeds that maintain welfare at higher temperatures