Dairy Cows Didn't Lay Down in Indiana Last Year!

New study confirms that heat-stressed dairy cows prefer to stand.

Published on: Mar 20, 2013

Ok, before you say, 'Duh, I could have guessed that,' read what these researchers found. It's part of the study of the behavior of animals. While some people are skeptical that it is important to know how animals behave, the net result can be designing systems that make animals more comfortable and improve performance.

Researchers at the University of Arizona and Northwest Missouri State demonstrated that you can tell how much a cow is stressed by whether she stands up or lies down.

The bottom line is that if you find your cows standing, they will pant more, eat less and produce less milk if they are dairy cows. These two research teams worked together to show that on hot days, cows prefer to stand. Finding your cows standing in the shade instead of lying in the shade on hot days is no accident.

Happy cows: These cows at Kelsay and Sons Diary, Whiteland, Ind., are standing, but not because theyre hot. It was a spring day. On a hot summer day, standing may indicate heat stress and decreased production.
Happy cows: These cows at Kelsay and Sons Diary, Whiteland, Ind., are standing, but not because they're hot. It was a spring day. On a hot summer day, standing may indicate heat stress and decreased production.

The scientists proved this was true by correlating body core temperature with the animal's behavior. When the temperature of the animal increased, they were more likely to stand. Or in other words, if they stand on a hot day, it's an indication that their body temperature is up, and they are suffering from heat stress.

The team used sophisticated sensors to get their measurements. While you may have always been told that temperature doesn't go up in the body just because it's hot outside and you feel hot, that's apparently not true for cows. Their core body temperature actually rose from 101 to 102 degrees F when heat-stressed. At the same time, they maintained a standing position.

Dairy producers could probably best use this information by installing coolers and misters to keep cows from overheating. When they overheat, cows' body temperature rises and they are less productive.

Obviously, many cows were likely standing in Indiana and the Midwest last summer. The temperature topped 100 degrees F at Indianapolis on nine days, and peaked at 106 degrees during the first week of July.