Some of the most basic precautions against the heat — assuring fans are working and that pigs have access to good air through proper ventilation – are only the first step to preventing heat stress, according to the National Pork Board. Adding misters/drippers and cool cells is another safeguard. If using misters, make sure water flow is sufficient to offer effective cooling since increasing relative humidity is counterproductive.

Loading and unloading pigs during early morning and late evening hours is highly recommended during periods of extreme heat, according to Sherrie Niekamp, NPB’s director of swine welfare. “Making sure trucks have all ventilation holes open and minimizing the amount of time the truck is not moving are key steps to avoid heat stress. When the truck is stopped on hot days, pigs’ body temperature will rise to dangerous levels quickly.

In extreme heat conditions, it is important to reduce the number of pigs loaded onto the truck.

In high temperature conditions, sprinkling the pigs with water just after loading can help cool the pigs once the trailer starts to move down the road. Niekamp says it is important to pay attention to the scheduled delivery time to avoid wait times at the plant. It is also a good idea to identify alternative travel routes to avoid travel delays due to road construction.

Those working with pigs during extreme high temperatures should follow basic hot-weather advice such as taking more breaks than usual, preferably in air-conditioned rooms, drinking water before thirsty and staying out of midday sun whenever possible.

As part of NPB’s Transport Quality Assurance Program, producers should follow these basic transport guidelines for safeguarding their animals during high temperature extremes: 

  • Adjust loading space and density
    Schedule transportation early in the morning or at night
  • Use wet shavings to keep hogs cool
  • Sprinkle hogs with water prior to loading at buying stations
    or on the farm (use a coarse heavy spray but not mist).
  • Do not use straw bedding
  • Remove slats from farm trucks
  • Open nose vents on trucks
  • Unplug ventilation holes
  • Load and unload pigs promptly to avoid heat buildup

Source: NPB