Compared to people, cattle have a distinct disadvantage when it comes to handling some kinds of heat. Soaring temperatures and high humidity are taking a deadly toll, a Kansas State University veterinarian said.
"Cattle lack the ability to sweat significantly, so it is critical that producers and livestock handlers take steps to reduce heat stress before conditions become dangerous," said K-State Research and Extension veterinarian Larry Hollis. "High daytime temperature by itself rarely causes problems. It is a combination of the humidity with heat that creates the maximum heat load on cattle."
He cited this month´s reports in Kansas of hundreds of cattle deaths attributed to the weather mix. Temperatures well into the 90 degree Fahrenheit range joined with high humidity levels to push heat indices to 105 degrees or above.
Other factors compounded the cattle´s lack of ability to perspire.
Several consecutive days of high temperatures, a lack of nighttime cooling, lack of shade or cloud cover, lack of wind, lack of air movement in pens, and grazing on endophyte-infested fescue pastures all can create problems for cattle, Hollis said.
In addition, animals with dark hides and/or heavy body weights, as well as those in advanced stages of pregnancy, are particularly vulnerable to the consequences of such weather.
"Producers should watch for signs of heat-related distress during hot, humid weather. The signs can include cattle going off feed, standing with their heads over the water source, panting, salivating excessively, or open-mouthed breathing," he added.
Producers and feedlot managers should consider ways to alleviate the stress, when possible, including:
• Avoid gathering or working cattle after mid-morning;
• Provide access to abundant cold water/waterer space and make sure the water flow rate is adequate;
• Provide access to shade;
• Provide the ability to move away from anything that reduces air flow, even cutting down weeds around pens;
• Use sprinklers - wet the skin;
• Control flies;
• Make arrangements with fire department.
"And, don´t forget about the people," Hollis added.