SAUK CITY, Wis. - Dairy farmers, take note: The key to turning your dairy cow into a cash cow is udder happiness.

That's according to a University of Wisconsin initiative that focuses on making dairy cows happier so they provide more milk

Nigel Cook has directed the effort since 2010. He and his team visit farms to give advice to farmers like providing bigger stalls, adding more air circulation, managing manure and using the fundamentals of cow welfare to ease stress.

They also provide workshops and created a website to share advice with farmers around the world.

Mitch Breunig owns 400 cows at Mystic Valley Dairy in Sauk City. He's spent over $100,000 toward improvements, and has seen milk production increase from about 13 gallons a milk a day per cow to 15 gallons.