NPR News: Most U.S. Dairy Cows Are Descended From Just 2 Bulls. That's Not Good

Most U.S. Dairy Cows Are Descended From Just 2 Bulls. That's Not Good
The drive to make more milk has had an unsavory side effect: Cows have become more genetically similar and less fertile. Scientists are trying to recover valuable genetic variation that was lost.

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at October 17, 2019 at 11:52PM
Health & Science