LINCOLN, Neb. – Extreme summer heat can be a cause for concern for feedlot operators and cattle producers in Nebraska. Heat causes stress and other negative impacts in cattle production. Cattle at a comfortable temperature are more productive, gain weight more efficiently and maintain a higher level of health.  

“I think our producers, for cattle welfare interests and good business sense, are very interested in managing that stress to maintain performance and prevent losses,” said Galen Erickson, Nebraska cattle industry professor in the Animal Science Department at the University of Nebraska-Lincoln.  “There are tools that many feed yards have implemented that really are to aid in cattle welfare in these heat stress events.”  

One advantage of the climate in Wyoming and the western Nebraska Panhandle is much of that stress caused by the heat is reduced, said Karla Wilke, cow-calf and range management specialist with the Panhandle Research and Extension Center in Scottsbluff. Consistently higher temperatures combined with greater humidity in eastern portions of Nebraska create an environment very different from the dryer regions in the western part of the state.

“Fortunately for us, because we get a lot of night-time cooling, we don’t have a lot of those issues,” Wilke said. “The cattle do cool down at night, which allows them to better regulate their body heat.”

Stress can still be an issue with finishing cattle, she said. And, with the pending start of the fall calving season, young calves can be particularly susceptible to the effects of hot days in the sun.

“The very young, nursing calf born in the heat like that will need a source of water they can reach and probably some shade until they reach the age they can regulate their body temperature,” Wilke said. “That newborn in a fall herd can dehydrate quickly if they don’t have access to a water source. When we do have those ucky, hot days, we need to think about that.”

A constant supply of water is also important for both cows and fat cattle, she said. It’s equally important to make sure stock tanks are up to the task of supplying water for both calves and mother cows.

“That’s something people should evaluate even for March-born calves,” Wilke said. “Is your tank big enough? Does it refill fast enough so that calf gets enough drinking water? Or, do the cows stand around and drink it so low a 400-pound calf can’t reach it?

“For finishing cattle, we’re going to have to keep an eye on them,” she said. “And if there’s an opportunity for shade, that can be very helpful to them.”

One helpful tool that producers can use to monitor weather and best manage agricultural resources with is the Nebraska State Climate Office’s Nebraska Mesonet calculator.  

Data pulled from the Nebraska Mesonet can be used to determine the cattle comfort index, a formula that accounts for temperature, humidity, wind, precipitation and sunlight and how those factors affect cattle health. The Nebraska Mesonet is a statewide weather observation network of nearly 70 stations, which records weather conditions every five minutes, 365 days a year.  

“It’s the comprehensive look at how stressed the cattle were leading up to now and how stressed will they be going forward,” Erickson said. 

The Mesonet Cattle Comfort Index, which is used worldwide, was developed and introduced as the Comprehensive Climate Index by Terry L. Mader and Leslie J. Johnson at the University of Nebraska, along with and John B. Gaughan at the University of Queensland in Gatton, Australia. 

“We can run the same equation year-round and give a value of what it feels like if you’re a cow out there, in real-time,” said Martha Shulski, State Climatologist and associate professor of Applied Climate Science.

The Mesonet also runs an experimental forecast tool that can help producers make prepare for conditions ahead.  

“The current weather, and how long cattle have been in certain conditions is important, but also looking at what conditions will be over the next two weeks may be more important,” Shulski said.  

In Nebraska, cattle can experience both heat and cold stress, but we have many tools to mitigate heat stress and heat stress tends to be a bigger issue for cattle producers than cold-related stress, Erickson said. To help cattle stay comfortable in hot weather, Erickson recommends producers focus on three main heat-mitigation strategies: sprinkling the ground with water to cool it down, providing cattle access to shade and creating additional water tank space. Air flow challenges may or may not be something that can be modified, but in some cases cannot be addressed. 

Cattle producers can also keep up with weekly and monthly weather updates from the Nebraska State Climate office to monitor current and upcoming heat index forecasts. 

“Farmers and ranchers do a good job of watching the weather and we want them to watch these indices, as well, to help them prepare. Not just ‘is it going to rain,’ but how comfortable are the cattle going to be tomorrow or this week.” 

For more information, see the Heath Stress Mitigation in Feedlot Cattle webinar, the Feedlot Heat Stress Information and Management guide or Preparing for Summer Heat article, courtesy of UNL Beef Extension and the beef quality assurance program.