Most of us have heard and/or used the term "sweatin' like a pig". As a matter of fact, pigs actually have very few sweat glands and can't use this mechanism to regulate their body temperature. As a result, they are very sensitive to hot summer temperatures. For this reason, we raise pigs in climate controlled barns that are automatically regulated to maintain the environment at a temperature at which pigs will thrive. Pigs outdoors are also susceptible to sunburn and must cover themselves in mud to try to regulate their body temperature.
To keep our pigs comfortable, we use mechanical ventilation systems that, basically, are composed of the following:
On one end of the barn, fans are located that will come on in stages as the temperature rises. When it is cool, only one fan will be on but as it heats up outside, other fans turn on until air flow through the barn is at maximum.
|In this picture, three fans are running, while three remain off|
In order to allow air into the barn, the fans are coordinated with a movable curtain on the other end:
As more fans turn on, the curtain lowers to allow more air flow. The air coming into the barn will flow over the pigs removing heat produced by the animals and carry it out of the barn.
In addition to controlling air flow, most barns are equipped with sprinklers that will mist the pigs at timed intervals. As the water dries off of the pigs, they will be cooled; similar to the principle of sweating.
All of these processes are regulated by electronic controllers that are connected to temperature probes in the barn. To ensure that the environment is always appropriately controlled, barns are equipped with an alarm system that will call the farmer if some component of the ventilation system isn't working properly.
When outside temperatures are cold, fans run on minimum so that pigs are not drafted by cold air and heaters, also controlled by the ventilation system, will be turned on to ensure that the barn stays warm.
Keeping pigs comfortable is our responsibility and a critical part of providing good animal care.