
Cows graze corn stalks in Pierceville, Kan., in 2018.
To safeguard livestock against cold stress as Arctic air masses take turns plunging into the Plains, a Midwest beef specialist has specific recommendations.
In the dead of winter with calving just around the corner, it’s important to be sure livestock are in their best body condition and provide them with additional energy source.
Cattle are most comfortable when they are in what is known as the thermos-neutral zone – a range of temperatures where they are not experiencing cold or heat stress.
“Right now, we’re in mid-winter, and we’ve had a chance to grow the animal’s hair coat. If we’re under dry conditions, the lowest critical (comfort) is 18 degrees,” said Dr. Justin Waggoner, Ph.D., a Kansas State University Extension beef cattle specialist based in Garden City.
This is where body condition scores come in. A 1 rates as being extremely emaciated and a 9 is extremely obese. As temperatures drop below 18 degrees, a cow categorized as a 5, would experience cold stress, Waggoner said.
Also important is considering whether there would be daytime warming, or whether by 3 p.m. temperatures might not warm much. Also, if cattle have a dry coat and in good condition, that makes a big difference going into a cold period and how the animal can withstand stress.
“If we have a cow that is in good condition and has had adequate time to grow that winter hair coat, she is going to be able to withstand colder temperatures better than a cow that is exceptionally thin,” he said.
Body condition equates to insulation. With a cow that’s rated a 4, you would see the 12th and 13th ribs. But with a 5, you wouldn’t see the ribs. Thinner cows experience cold stress at higher temperatures.
Under cold stress, the animals’ energy requirements are increasing, not to be confused with protein requirements. There is a 1% increase for every degree below the critical temperature of 18 degrees.
“It’s not unusual to see a 10% increase,” Waggoner said.
He advises producers to choose a quality alfalfa hay. But that’s not the only choice, he said.
Rather than feed a protein supplement to compensate for energy needs, he likes a combination supplement. He looks for a decent protein profile with a good energy such as dried distillers grain, any by-product feed, or a blend of corn and dried distillers grain.
“You can replacing the grazed forage with the hay (alfalfa) as well as, in some cases, using a supplement like dried distillers grain or any by-product feedstuff,” Waggoner said.
If on milo, then a high quality grass hay that was grown this summer is an option.
“Pound for pound, we’re trying to get good quality,” he said.
Rain, snow and wind complicate the situation.
When cattle’s hair gets wet, it reduces the ability to trap air and insulate the cow, he said.
“With a wet coat, a cow can experience cold stress even at 60 degrees,” he said.
Since a heated barn is often not available, Waggoner says cattle are generally robust creatures used to taking advantage of topography such as draws or shelter to get out of the wind.
Any sort of windbreak that producers can put out for the cattle; be it a temporary or permanent structure, is helpful. Having sufficient length of that windbreak is important, too.
“People are very creative, using cornstalk bales, bales stacked on the edge of cornstalks or milo stalks,” Waggoner said.
Reporter Amy Hadachek is a two-time Emmy Award winning meteorologist and a storm chaser who earned her NWA and AMS Broadcast Meteorology Seals of Approval. She and her husband live on a diversified farm in Kansas. Reach her at amy.hadachek@midwestmessenger.com.