With the numerous health and environmental challenges upsetting the pig industry at present, the summer heat is one seasonal condition producers cannot afford to let stifle their profitability. When managed poorly, the heat can take a serious toll on performance, especially in finishing pigs.

Heat and wide fluctuations in temperature can often cause immense stress for the animals, resulting in lower performance and health problems.

“Even during the hottest time of the day, pigs are still producing additional body heat from eating and moving around the barn. Since pigs have few sweat glands, cooling off by perspiration is not much of an option,” said Russell Gilliam, U.S. swine business manager for Alltech. “Respiratory rates begin to increase around 70 degrees Fahrenheit, and with high humidity it becomes difficult for pigs to find relief from the heat on their own.”

According to Gilliam, temperature fluctuations that continue into the fall season produce additional challenges. Wide variations between night and day temperatures can compound stress levels that the animals already experienced from increased temperatures.

Besides monitoring the barn’s temperature, Gilliam said there are many signals that indicate a pig is too hot. Some of them include: faster breathing, fluctuations in feed and water intake levels, reduced activity and lying stretched on the floor  and separation from other pigs. Maintaining barn temperature and increasing ventilation are important in keeping the pig’s stress levels to a minimum.

“If you can avoid temperature shifts by a few degrees or more, you will be making the pig’s habitat more comfortable, which can lead to better profits,” Gilliam said.


Since pigs can generate large amounts of heat, pig handlers should focus on practices that produce less heat. That includes ensuring each pig has enough space and ventilation, minimizing motion and not disturbing the animals during peak temperature times of the day. It is also important to make sure the pigs have unlimited access to fresh and cool drinking water, as drinking levels can also have a major effect on feed intake.

Data has also shown that offering pigs a combination product of organic acids, electrolytes, enzymes and probiotics can address gut health issues during times of stress in young animals. It works quickly by lowering the pH of the water. Depending on the type of water and the target level for pH, the technology can work on its own or with a combination of other ingredients, such as probiotics to help optimize the gut environment. Organic acids can help grow probiotics in the gut and the enzymes can help enhance intake and digestibility. Electrolytes make sure the animal stays hydrated, especially in times of heat stress.

In a recent study, Alltech’s Acid-Pak 4-Way was administered through drinking water for the entire nursery period as a replacement for an existing antibiotic, vitamin and mineral program (FRIO, A.J.L., YU, E., AND R. SANTOS; 2009). In terms of overall performance, the researchers found the combination acidifier maintained optimum conditions for digestion in the stomach and small intestine to allow the pigs to maintain electrolyte balance and pH levels.

“Addressing heat stress and being prepared for its effects can have a major impact on the performance and overall value of your pigs when you take them to market. It can also help reduce the cost of added days on feed and additional health costs,” Gilliam said. “In times of stress, pigs can be more susceptible to disease and health challenges. It is essential your pigs’ nutrition is equipped with technologies that build their natural immunity.”