Agriculture Secretary Sonny Perdue said Tuesday at the World Dairy Expo in Madison, Wis., that there are no guarantees that smaller family dairy farms in the U.S. will survive due to changing business models and economic struggles, per the AP.

"In America, the big get bigger and the small go out. I don't think in America we, for any small business, we have a guaranteed income or guaranteed profitability."

Why it matters ... Small Wisconsin dairy farmers are struggling due to a variety of factors: plummeting milk prices, a pivot to milking in mass quantities, the Trump administration's trade war with China and rising suicide rates for farmers.

By the numbers: The "Dairyland" state lost 551 dairy farms so far this year. It lost 638 in 2018 and 465 in 2017, per Department of Agriculture data.

U.S. dairy solids exports to China fell 43% overall after China's first round of retaliatory tariffs in July 2018. It left 3.7 billion pounds of milk in limbo, forcing farmers to find other markets, according to an analysis by the U.S. Dairy Export Council.

"It's very difficult on an economy of scale with the capital needs and all the environmental regulations and everything else today to survive milking 40, 50, or 60 or even 100 cows," Perdue said.

Go deeper: American farmers are pivoting to solar power to pay the bills