USA Today:

China is in the grip of a massive donkey shortage caused by soaring demand for e’jiao — a traditional medicine made by boiling donkey skin. Demand for e’jiao has doubled since 2010, hitting nearly 15 million pounds a year in 2015, according to the national e’jiao association.

The substance was once affordable only by royalty, because one donkey yields 2.2 pounds of e'jiao. 

Only 30 years ago, China had 11 million donkeys — the largest herd in the world — but the number has dwindled to between 3 million and 5 million, despite intensive breeding programs.

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