Pigs do not sweat all over their body- just the sole of their paws.
"I´ve read everything I could find relating to this subject and this what I´ve discovered:
The only place guinea pigs sweat is on the soles of their feet, nowhere else.
Guinea pigs, along with most other mammals, do not have widespread eccrine sweat glands like humans do.
The eccrine sweat glands produce the thin, watery secretion which aids the human body in maintaining a constant temperature. In most mammals, with a few notable exceptions e.g. the naked mole rat, the eccrine glands are found only on the of the soles of the feet and palms of the hands, where the secretions aid in friction rather than regulating body heat. Pigs (hogs, not guinea pigs) also have eccrine glands in the hairless skin of their snouts.
All references I have found to the use of rodents in laboratory experiments relating to eccrine glands make use of the skin from the soles of the footpads.
Guinea pigs use several methods to regulate their body temperature:
They seek shade to cool off or huddle with others to keep warm.
They shiver and fluff up their fur to keep warm, as well as burning brown fat deposits.
Their bodies respond to heat by increasing the blood supply to the skin, where it is cooled by the surrounding air (particularly in hairless, thin areas like the ears). In pink skinned animals you can see the skin of the ears reddening as the blood supply increases. Other rodents use the naked areas of their tails in the same way. Being tailless, the guinea pig is at a disadvantage and therefore particularly susceptible to heatstroke when the temperature of the surrounding air rises above it´s body temperature.
Correspondingly when in a cold environment, the supply of blood to the skin is reduced, thus conserving body heat.
So, there you have it folks. Keep those pigs in a comfortable temperature, around 65 - 75deg F is ideal. "
Found this here: (broken link removed)