More efficient cows led to an incremental increase in milk production during May while the dairy herd held steady.

USDA says production in the U.S. during the month totaled nearly 20 billion pounds with production per cow up 10 pounds from last year.  

The herd size increased 12,000 head on the year but remained unchanged from April. 

South Dakota and Kansas have the largest increases in milk production in May, up 6.2 percent and 3.6 percent respectively. 

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