Another possibility for many holding pens is to install an open ridge to exhaust hot air. Water sprinklers or sprayers located in feed lanes and holding areas promote evaporative cooling. Any water application in high humidity areas requires the use of fans for effective cooling, otherwise cows stand in a steam bath. Please note that spraying or sprinkling cows is stressed. Misting tends to allow small water droplets to collect on the hair and insulates the cow, reducing heat loss.
Sprinklers have large water droplets, which wet cows to the skin for maximum evaporative cooling.
Low pressure nozzles, timers, pressure valves and thermostats are available through irrigation equipment installers, hardware suppliers and nursery suppliers. Low pressure nozzles generally deliver larger water droplet sizes for better hair penetration. Size piping according to the length of the run. In most dairy operations, operate sprinkler systems on a cycle of 30 to 90 seconds spraying and 4 to 5 minutes of fan operation during the hot hours of the day, particularly noon to 6 p.m. Initially mount fans and sprinklers on a temporary basis to allow adjustment based on prevailing winds and effective sprinkling of the cattle.