Keeping Cattle Cool This Summer
By David Elstein
July 10, 2002
Records for high summer temperatures
have already been set in parts of the United States this year. While humans can
retreat to air-conditioning and drink cold beverages, animals are not that
lucky. If they can't stay cool, dairy cows produce less milk and beef cattle
gain weight more slowly.
Now Agricultural Research Service
scientists at the Roman L. Hruska U.S. Meat Animal Research Center (MARC) in Clay Center, Neb., have new
information that helps producers recognize overheated cattle and protect the
animals when temperatures rise.
There are a few ways to check the effects of temperature on cattle. One is
to compare the temperature and humidity to a graph to see if the animals are in
the danger range. Another way is to measure the animals' respiration level.
Cows lose heat primarily through respiration and will begin to pant if they
During hot days, operators can count, with a stopwatch, the breaths per
minute (bpm) of a few cattle to see if they exceed the healthy 60 to 80 bpm
level. To simplify this process, ARS agricultural engineer Roger Eigenberg has
developed a respiration monitor that will be available in the near future. The
nonintrusive device, strapped to the animal, has a sensor that measures its
respiration. A small computer stores the information and converts it into
Researchers suggest two general ways to help animals when they are heat
stressed. One way is with a sprinkler system. ARS agricultural engineer John A.
Nienaber notes that watering should be done intermittently to allow the animals
to dry, because evaporation cools them. Another way is to provide shade or
shelter for the animals. These devices may save the farmer money by keeping
production relatively stable. Nienaber also suggests not working with cattle
during very hot, humid periods.
Read more about this research in the July issue of Agricultural
ARS is the U.S. Department of
Agriculture's chief scientific research agency.