The nation’s dairy farms are in the midst of a crisis, and for the first time since the 1970s dairy emergency, the milk industry is in danger of being tossed away like a crumpled milk carton.

Dairy farmers are fighting to preserve what took years, and in some instances, generations to build.

In Vermont, for example, 32 of the state’s 1,050 dairies have folded in 2009.

“Dairy farming in Vermont is vanishing and a unique lifestyle with it,” said Karen Irvine, owner of Culinary Communications, a New York City-area firm that works with the dairy industry.

The West Coast herds, and their owners, have taken a hit, too. In California, thousands of dairy cows are being turned into hamburger because milk prices have dipped so low that many farmers can no longer afford to feed them.

Federal livestock data indicate more than 72,000 dairy cows were culled last January alone. Industry experts said more than 1.5 million of the nation’s 9.3 million milk cows could be headed to the slaughterhouse in the months ahead as a way to cut costs.

The root of the problem isn’t singular. Low prices from processors, high feed and fuel costs, shifts in consumers’ dairy consumption, and the weakened global economy intertwine, all combining to send dairy producers into a tailspin.

In the last year, dairy farmers’ revenue dropped to around $1 a gallon. That’s a 40 percent decrease since the end of 2008.

Considering it costs, on average, $1.50 to produce a gallon of milk, the nation’s dairies are drying up. Using these figures, the Farm Aid organization estimates farmers are losing nearly $200 per cow per month.

Around the country, milk payments range from $9 to $12 per hundredweight of fluid milk, which is equal to about 11.8 gallons of milk.

To break even, farmers need to earn between $17 and $27 per hundredweight, taking into account production costs in various regions of the United States.

Feed costs escalated in the last year, thanks to competition from the ethanol industry for corn. In the past three years, the demand for corn has doubled, pushing feed ration prices even higher.

The University of Minnesota Extension Department said ration prices have climbed by $1.10 per cow per day since 2003. Higher prices have dairy farmers reconsidering exactly how much and what kind of ration to feed, especially since feed costs total 50 percent of milk production costs.

Fuel prices shot up 35 percent in 2008 and fertilizer prices doubled, said the University of Wisconsin Department of Agricultural and Applied Economics.

Stacey Fletcher of the American Dairy Council said one of the main causes of the current crisis is the global economy.

Dairy exports had grown from $1 billion a year to nearly $4 billion in 2008, thanks to increased demand in developing countries, where the introduction of fast food had bolstered the dairy industry.

“Dairy has relied heavily on the export market, coming off a record year in 2008, and thus, when that demand simmered, as it has this year, it hit the industry hard,” Fletcher said.

Now, global demand is at a standstill. Decreased consumption of milk, cheese and butter can be tied to economic challenges.

Kristen Dumermuth, communications coordinator for the U.S. Dairy Export Council, said the global economy is cyclical and will experience ups and downs.

“We can’t afford to be in the export market just when conditions are right. We have to become consistent exporters committed to producing the right product for the right customer at the right price all the time,” Dumermuth said.

The calamity experienced by the industry hasn’t escaped U.S. Secretary of Agriculture Tom Vilsack and members of Congress.

Relief funds of $290 million were approved as part of the 2010 Ag Appropriations bill signed into law in October, and Vilsack said he expects dairy owners will receive direct payments before the holidays.

Vilsack said the dairy relief package totaled $350 million and $60 million will be used to purchase cheese for government food programs.