A surprising conclusion. Cows are traumatized by encounters with predators.
Cows that survive encounters with wolves may suffer from symptoms similar to post-traumatic stress disorder, according to a new Oregon State University study.
Researchers said they were told by ranchers that such cows are more aggressive, sickly and eat less. The memory of a wolf attack can also lead to decreased pregnancy rates and lighter calves for those animals that do give birth.
To measure the stress of a wolf attack on cows and estimate its lingering effects, researchers simulated a wolf encounter with 100 cows. Half of the cows had never seen a wolf, while the others had been part of a herd that was previously attacked on the range.
Researchers found that cortisol, a stress hormone, increased by 30 percent in cows that had previously been exposed to wolves. They bunched up in a corner, formed a protective circle and acted agitated.
Their body temperatures also increased rapidly, researchers said, another indicator of stress.
The cows previously unfamiliar with wolves were curious about the dogs and did not show signs of stress.
How much to they understand? Obviously this type of stress is bad. What about other animals or people who have to deal with violence in their lives and the subsequent stress. This is an interesting finding. It’s not that surprising, I guess. We all have mammalian brains.