About the Comfort Index

Mader and co-workers at the University of Nebraska developed the Comprehensive Comfort Index to incorporate both extremes of hot and cold into one index value. It is unique in that it includes, in addition to air temperature and relative humidity, effects of wind speed and solar radiation. Development and validation of the index used data from beef and dairy cattle.

Actual animal response to temperature stress will be dependent on a number of factors not accounted for in the index. Those include, but aren’t limited to, age, hair coat (winter vs summer; wet vs dry), health, body condition, micro-environment and acclimatization.

Heat and cold stress level categories for the cattle comfort advisor:

Comfort level	Map indicator	Index Value, ⁰F	General Interpretation
Heat Danger		> 105	Animal deaths may exceed 5%
Heat Caution		> 95 to 105	Decreased production, 20% or more Reduced conception , as low as 0%
Heat Caution		> 85 to 95	Decreased production, 20% or more Reduced conception , as low as 0%
Comfortable		77 to 85
Comfortable		32 to 77
Comfortable		15 to 32
Cold Caution		< 15 to -20	18 to 36% increase in dry matter intake
Cold Danger		< -20 to -40
Cold Danger		< -40

Adapted from: https://www.mesonet.org/images/site/Using%20the%20Mesonet%20Cattle%20Comfort%20Advisor(1).pdf