Here’s fascinating research reported in the Daily Mail:  Cows have herd mates and the bonds can affect yields, according to UK researchers.

Krista McLennan, an animal welfare researcher at Northampton University measured heart rates and cortisol levels of cows to see how they cope when isolated, penned with their best friend or with an unfamiliar cow. “When heifers have their preferred partner with them, their heart rates are reduced compared with if they were with a random individual,” McLennan said. “Keep an eye out for those cows which like to keep their friends with them. It could have some real benefits, such as improving their milk yields and reducing stress.”

I’ve noticed this myself. Just the other day, the herd was walked past a paddock of two-year-olds and I watched one of them gallop up to sniff noses across the fence with two herd members. The amazing thing was that their ear tags revealed they were all born in the same year. What I’d assumed was a two-year-old turned out to be a three-year-old late-calver conveniently paddocked with the younger ones. Old friends were catching up!