"Fans alone are not enough," Garcia said. "Treating cows under severe heat stress with sprinklers or fans alone is not enough. Both strategies need to be combined."
He adds that the effectiveness of the cooling system depends on the number of rows of cubicles; four rows, then the sprinklers over the feed bunk and two rows of fans, one over the cubicles, one over the feed bunk, if working with two rows, then one row of sprinklers over the feed bunk and one of fans over the cubicles.
He warns dairy producers about the risks associated with high-pressure misters.
"High-pressure misters reduce the amount of water used, but eject very small droplets and when incapable to soak completely the coat and skin," he said. "They create an air space between the skin and the water film which insulates and impairs heat dissipation. To achieve cooling they must work with a minimum water flow of 3.4 gallons per hour with 5 minute cycles."
He explains that if the temperature is 86 degrees, the soaking cycle frequency needs to be every 8 minutes, (1 minute on, 7 minutes off.) When body temperature exceeds 68 degrees, the fans should work continuously.
"Supplemental fan cooling, in combination with low pressure feed bunk sprinklers can reduce the effects of heat stress on milk production and intake," Garcia said. "Providing clean and fresh water, enough shade and adequate air circulation is critical to maintain production. These systems should be accompanied of key nutritional management strategies suggested for hot weather."
Todey says near average temperatures will prevail later in the week. But warmer temperatures will return in coming weeks. For more information on keeping dairy cows cool, visit iGrow.