UNIVERSITY PARK, Pa., June 29 -- Pennsylvania State University issued the following news release:

After a cold winter in western Pennsylvania, Old English Acres Farm owner Ed Clark noticed something was off with his herd of cattle.

Several cows weren't gaining weight normally, but the cause wasn't immediately clear. Clark first tried treating the issue himself, giving the animals mineral supplements while sending blood samples to Michigan for testing. Two weeks later, the results pointed to a trace-mineral deficiency.

The diagnosis kicked off a months-long process of adjusting mineral packs, testing feed and water quality and waiting through multiple rounds of results before fully understanding what was affecting the herd. By the end, ...