HUTCHINSON—Heat stress in cattle is an issue in Kansas during the summer. With temperatures this week expected to soar to 106 degrees Fahrenheit in western Kansas and above 101 in central Kansas, ranchers need to give extra care of their animals. Along with the severe high temperatures, other factors can affect cattle.
"Some cattle are more vulnerable than others," said Bradon Wiens of Wiens Wagyu in Plains, Kansas. "Having a calf on them puts more stress on them."
Wiens tries to keep his animals in the shade, give them plenty of fresh water and counts their respiration to make sure they are okay. In addition to his Wagyu cattle, he also raises Angus.
A.J. Tarpoff, a beef veterinarian with K-State Research and Extension, said cattle are resilient animals and will often acclimate to hot temperatures. But some factors, including their hide color, diet, humidity and whether temperatures cool down overnight, will affect the animals ability to thrive in heat.
According to the U.S. Meat Animal Research Center, animals with a black or dark red hide are more susceptible to heat than lighter-skinned animals. Also calmer animals fare better than high strung ones.
"It really is a multi-layer challenge," Tarpoff said in a release. "Each animal within a group or pen is not affected the same way. Animals with higher body condition scores, or with darker hides, or finisher steers and heifers that are getting ready to go to harvest are at higher-risk of heat stress."
According to Tarpoff, cattle eat less during hot weather and sweat 10% as much as humans. Because of this, they pant to help with heat.
"As temperatures rise and their heat load increases, they will start breathing faster," he said. "They are dissipating heat through tiny droplets in the respiratory tract."
Doing so, however, causes cows to eat less, setting them on a path to poor growth and future performance.
"The internal temperature of cattle will peak two hours after the hottest point of the day," Tarpoff said.
Animals that have elevated breathing, are drooling and restless are showing the beginning signs of heat stress. According to USMARC, once the cows have an open mouth with their tongue protruding, are breathing heavily and have their head down, they are in an advanced state of heat stress.
Tips for reducing heat stress in cows:
•Handling. Receive, ship or move cattle only during the coolest parts of the day, preferably before 10 a.m.
•Feeding. Modify feeding times. Feed 70% of the animals’ ration as late in the evening as possible. This puts the peak heat of digestion overnight when temperatures are likely cooler. Decrease feeding during the day.
•Managing heat. Split cattle between pens or reduce stocking density. Maximize airflow by removing obstructions around facilities. If feasible, install shade structures, which can reduce solar radiation and reduce the temperature on the pen’s floor. Install sprinklers to wet cattle down at night or early morning so as not to increase humidity.
•Water. Make sure there is plenty of fresh water. Cattle should drink five times as much water as they do dry matter.