A handful of companies have taken over dairy production, pushing the prices paid to farmers well below the cost of production & encouraging overproduction.

This has forced most small & mid-sized dairy farms to close while large farms have grown larger.
http://www.foodandpower.net/2020/06/18/fewer-global-dairy-corporations-drive-overproduction-and-pollution-harming-small-farmers-report-finds/

Consolidation in the dairy industry hasn't just undermined rural economies - it's been bad for the environment too. The total combined emissions of the world's 13 largest dairy corporations rose by 11% in just two years.

To protect family farmers, rural communities, and the environment we need to stem the tide of consolidation in the dairy industry. One of the key ways to do this is through supply management, which prevents overproduction, balances supply and demand, and stabilizes prices.