What makes a pig in the mud as happy as … well, a pig in the mud? Mud baths certainly keep pigs cool, a newly published research review finds, but wallowing may also be a sign of well-being in swine.

Pigs and mud go together like...well, pigs and mud. They're a classic combination. But did you know there's a reason why these animals like to spend their time in the muck? There are actually several, ...