Cows Have Best Friends

Cows have best friends.

In a 2011 study at the University of Northampton, researchers foundy cows have lower heart rates and less cortisol - a stress hormone - when with their preferred partner. When separated from their best friend, heart rate jumped and they became agitated.

Farmers have long noticed cows lick and nuzzle specific herd mates, and will stand together for hours. Each cow has a social network, with 2-4 close friends. Calves form friendships within days of birth that can last years.

When a cow's best friend is removed, it will often stop eating and bellow for days. When reunited, they groom each other. The study measured heart rate variability and found friendship literally calms the heart. It is why Temple Grandin argues cattle should never be isolated - they are herd animals with emotional bonds as complex as dogs.