milk production

From fans and misting water to creating a whole new breed of cow, farmers and researchers are fighting rising temperatures to keep the dairy industry from losing millions of dollars to "heat stress."

Large-scale dairy farms are more lucrative, and national milk production has actually increased. But small farmers like David Fuller, who is auctioning off his last herd, see their way of life dying.

Milk is like oil - it's refined into products that are traded globally. So global events can mean profits or losses for dairy farmers. This year, they're seeing losses, and asking Congress for help.