Wouldn't it be cool if your parents allowed you to wallow around in a big puddle of mud all day long? As a matter of fact, that's EXACTLY what it would be. Just ask a pig. Mud is cool!
When humans get hot, we sweat. Our bodies need to stay about the same temperature — 98.6° F — all the time.
As you sweat, the water evaporates into the air and cools the skin beneath it. Unfortunately, pigs have very few sweat glands, and the ones they do have don't work very well.
As a result, pigs can't sweat like we do. So what's a pig to do when it gets hot?
You guessed it: Wallow in the mud! Rolling around in the mud helps to keep pigs from overheating when it gets too hot outside.
Some pig farmers now use water sprinklers instead of mud to keep pigs cool in warm months. Mud, however, tends to keep pigs cooler longer because the water in mud evaporates more slowly than pure water.
Just because pigs like to roll in mud, don't assume that they're dirty animals. To the contrary, pigs tend to be very clean animals.
For example, if you spend much time around a pig farm, you'll find that pigs keep their “bathroom" as far away as possible from the areas where they eat and drink.
If given the choice, pigs would probably prefer to stay in an air-conditioned barn rather than roll around in the mud. Since they spend a lot of time outside, though, rolling in the mud does have other benefits.
You've probably noticed that most pigs are not very tan. In fact, their light pink skin can get sunburned very easily.
A good thick layer of mud also helps to protect pigs from insects. Flies, parasites and biting insects are often drawn to the areas where pigs live since there is often food nearby. Mud helps to keep harmful insects away from pigs' sensitive skin.