MU heat-stress researchers measure sweat rate in cattle

US - Using a device resembling an electric razor, University of Missouri researchers are measuring sweat rate in cattle in search of ways to help producers overcome heat stress in their herds.

7 November 2006

2 minute read

North America

Heat stress can be a major factor in limiting cattle growth and reproductivity.

Cattle sweat more in the shoulders than in the rump area due to a higher number of sweat glands, but different breeds sweat at different levels when exposed to heat, said Don Spiers, associate professor of animal science.

Spiers and other researchers studied three groups of cattle: Angus raised in Missouri, and Angus and Romosinuao raised in Florida. They compared sweat rates and corresponding body temperature of the three groups.

The Romosinuaos are noted for heat tolerance. They sweated less than the Angus from either state, but maintained a lower body temperature, he said.

"That means they must be doing something else to lower body temperature. These animals are slower-growing than Angus, which suggests lower metabolic rate," Spiers said.

The lower sweat rates may be the animals' attempt to preserve body moisture, making hydration a critical factor.

"We are going to look for genetic markers for animals that will do better in the heat, and sweating is one of the parameters we are looking at," he said.

"Hopefully, we can find these markers in a blood sample and give (results) to breeders to select for animals that have this trait."

"The Romosinuao are the same genus and species as Angus, which means there should be less variance between the animals so we should be better able to pick up any difference in their ability to tolerate heat," Spiers said.