ELLSWORTH, Wis. - You can tell the sun is really beating down on the Hines dairy farm when the principle milker trades her bib overalls for shorts.
"Then you get more dirt and everything on you, but it's worth it to keep cool and such," says Alyce Hines, who milks the herd of roughly 60 cows for her uncles Dale and Dean.
As a pre-vet student at UW-River Falls, Alyce knows this week's heat wave isn't just uncomfortable for her.
An extended heat wave last summer caused a 30 percent milk production drop on the Hines farm.
Across Minnesota and Wisconsin hundreds of cows died.
"Yep she's panting there, she's hot," says Dean glancing toward a cow with its tongue hanging out.
Dean says cows can handle a few hot days, but the longer the heat wave lasts the more damaging the effects on livestock. Heat-stressed cows often go off feed. The impacts on milk production can last for months after the heat dissipates.
"If this holds on for the next four or five days, it could be very crucial for casualties in the dairy business," says Dean Hines.
Paul Bauer, the general manager of the Ellsworth Coop Creamery, says he hasn't seen a drop in production from his farmers - yet. "But we know it's coming."
Bauer says overnight lows can be just as important as daytime high temperatures, since cool nights can give cows a chance to cool down.
Fans are going round the clock in the Hines' barn with extra waterings for calves outside.
"Constant filling of water buckets because they're drinking it that fast," says Alyce.
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