A dairy cow enters the milking parlor at the Hunter Haven Farms dairy farm in Pearl City, Illinois, U.S., on Friday, March 30, 2012. Photographer: Daniel Acker/Bloomberg
A dairy cow stands in the milking parlor at the Hunter Haven Farms dairy farm in Pearl City, Illinois, U.S., on Friday, March 30, 2012. Photographer: Daniel Acker/Bloomberg
A dairy cow walks back to her barn after being milked at the Hunter Haven Farms dairy farm in Pearl City, Illinois, U.S., on Friday, March 30, 2012. Photographer: Daniel Acker/Bloomberg
