Livestock farmers last week were making plans to keep their livestock safe from the summer heat as temperatures were forecast to hit 90 degrees and above throughout the state.

Alle Bailey of Diagonal in Ringgold County said her cattle on pasture have access to shade and fresh water. She said they adjust their chore time to coincide with cooler parts of the day.

"We don’t work them or move them in the heat. We check them early in the morning and later in the day. Otherwise, they’re laying in the shade and won’t get up," Bailey said.

Craig Recker raises cattle in monoslope and confinement barns in New Vienna in Dubuque County.

With larger cattle, almost ready for market, Recker said he was keeping a close eye on his cattle.

"The buildings really help quite a bit for cooling cattle as long as you can get air moving through there," he said. "You still have to be on the ball watching them, though."

Adjusting rations

Choring is a bit different during the heat, he said. He feeds his cattle twice a day during periods of extreme heat and switches up the rations to make up for the hotter temperatures.

He adjusts the rations and splits feeding time to twice a day so the feed doesn’t spoil.

Iowa State University (ISU) Extension beef veterinarian Grant Dewell says farmers should evaluate cattle closely and pay close attention to dark-hided cattle, which are more prone to heat stress.

"Special attention should be paid to cattle with increased risk of heat stress including heavy cattle, black or dark-hided cattle and respiratory-compromised animals," Dewell says in ISU’s Heat Stress in Beef Cattle pamphlet.

Compared to other animals, cattle cannot dissipate their heat load very effectively at high temperatures, Dewell points out.

Cattle rely on sweating as their primary method to maintain core body temperatures, but high temperatures above 90 degrees accompanied by solar radiation means their large body surface area begins to accumulate more heat than they can disperse by perspiration.

"At this point, cattle switch to respiration (panting) to cool themselves," Dewell says.

The use of sprinklers or misters can also help cool cattle, but that doesn’t take the place of adequate supplies of fresh drinking water, he said.

"When installed, sprinklers should be operated intermittently to avoid mud and increased humidity," he said. Sprinklers should be placed away from feed bunks and water tanks to make sure that cattle don’t reduce feed or water intake, he said.

For more information on ways to manage heat stress in cattle, go to www.iowabeefcenter.org/news/HeatStressAwareness2017.html.