Heat Stress is a Big Deal

Between death loss and production impact, the estimates have the yearly cost to the U.S. swine industry to be around $300 million so far this year. Don’t ignore heat stress.   While you can’t control the weather,  you can control your facilities.

Pigs don’t sweat, so they cannot naturally take advantage of evaporative cooling. They rely on panting to cool themselves. Panting isn’t going to do the job for all pigs in hot weather, so you are going to need facilities that help you keep your pigs cool.

The sow farms I work with frequently use cool cells. The biggest issue I see with cool cells are dry areas on the pads. These spaces allow tons of uncooled air into the pig space. It is like leaving a window open next to your AC unit. To help prevent this, flush your lines and check if the system is feeding water across the whole cell.

Evaporative cooling is the other main system I see in both sow farms and finishing floors. The main objective here is to mist or drip the animal with water and then allow the water to be evaporated off the skin of the animal. It is the evaporation step that cools the animal more than the misting or dripping with the cool water.

In order to be successful with this the water needs to get to the skin of as many animals as possible and the water needs the opportunity to evaporate.

Misters and drippers love nothing more than to clog, and it’s not uncommon for me to walk barns with < 50% of their misters functioning properly.

The one pig getting the drip may be at a lower risk of heat stress, but the rest of the pen is seeing zero benefits from the investment in facilities.

Upon running your misters, walk the barn and fix any misters that are not working properly. 

Just as important as a properly working mister is the water needs the opportunity to evaporate.

Lack of air movement and too short a time period between misting can hinder the evaporation process.  Dead spots in air movement can be greatly helped by having stir fans in the barn and having all the fans functioning outside the barn. The timing of misters can be an easy fix within your controllers.

After changing the timing of your misters keep an eye on your pigs.   If they are still covered in mist, it is too early for the misters to run again. Remember that the evaporation is what does the majority of the cooling, not the misting with water.

Before it gets too hot, check your facilities for other basic ventilation items as well. Check to make sure soffits are open and clear of debris so they can pull in air, make sure curtains can drop fully without hang-ups in the corners, confirm all fans are functioning, and all fans/sutters are clear of debris. For sow farms, don’t be afraid to turn off heat lamps on hot days.

When in doubt, focus your attention on the animals at the highest risk for heat stress. The older the pig and the more pregnant, the higher the risk. These also happen to be the animals into which you have the greatest investment. Spend the extra time in the due to farrow row in your gestation barn or the market hogs in your finisher. Your effort is worth the impact.

We can’t control the local weather yet, but we can have a good understanding of how to mitigate heat stress and have working facilities that are ready to help. Controlling heat stress is the right thing for the farmer, the pig, and the consumer.  Please contact your veterinarian or our swine specialist team with questions. Our swine specialist team can be reached at 507-562-PIGS (7447).

Cara Haden, DVM, Pipestone Veterinary Services