Look at Private Peterson. Look at Private Peterson milk Lulu. Milk Lulu, milk. Private Peterson loves Lulu. Lulu loves Private Peterson.
And so this fellow became the pin-up poster for dairy cows across the country in the 1940s. There wasn't a milking barn that didn't have this photo tacked to the wall to keep the cows dreamy eyed and contented while they were milked.
Click on image to see it larger.
The National Dairy Corporations ad in the 1943 National Geographic proving they too were part of the war effort.
Seriously, I haven't a clue what cows used to relax in the 1940s.