Pigs can't cool themselves through sweating and need special attention during heat waves, says University of Missouri Extension swine nutrition specialist Marcia Shannon.
Pigs take priority over any other animals on the farm when temperatures rise, Shannon says. Pigs have few working sweat glands to remove body heat.
Shannon offers these tips:
Provide an adequate, constant supply of fresh drinking water cooled to room temperature or lower.
Water flow rate should be at least 1 gallon per minute for sows with litters and 0.5-0.6 gallons per minute for finishing pigs.
Run cool water using a hose or sprinkler over the pigs' skin to cool them. Let skin dry before wetting again.
Provide outside pigs shade and mud holes for relief. When pigs roll in the mud, it cools their skin and prevents sunburn.
If you notice overheated pigs, move them away from other pigs, Shannon says. Wet their skin with cool, not ice-cold, water. Let them dry. Repeat process as needed. Put fans on them to increase air movement. Make sure the space is adequately ventilated to remove the hot, moist air from the area.
Watch for stressed breathing patterns or panting. It is one of the first signs of heat stress in pigs. Count breaths to check for stress. More than 50 breaths per minute indicates stress.
Pigs don't eat as much when it is hot. Eating and digestion generates heat, so pigs eat less to control their internal body temperature. Producers could consider changing rations by adding more fat to minimize heat increment and increase energy. When doing so, also increase protein in their diet. Another option is to add cool water to their feed to stimulate intake.
Pigs will sprawl out over a larger area of cool floors or ground to try to keep cool. They'll also move less to avoid overheating.
Pigs breed less during heat stress, so expect lower conception rates. The heat lowers semen production in boars.
Confinement operations can take simple steps to reduce heat also, says Joe Zulovich, MU Extension agricultural engineer. First, clean fans with brooms or power washers. A dirty exhaust fan system can reduce airflow by half.
If ventilation is adequate, inside temperatures should be no more than 3-5 degrees higher than outside temperatures. If not, check and clean fans, grilles and shutters. If inside temperatures still remain more than 3-5 degrees above outside temperatures, the ventilation system needs to be evaluated by a ventilation system professional.
When inside temperatures reach 85-90 F, wet pigs with water hoses or sprinklers. Let them dry between wettings. When relative humidity levels are above 70 percent and when temperatures are above 75-80 F, wet pigs to cool them.