Donkey polo was a popular game in ancient China among some sections of society.
The trade has placed unprecedented pressure on global donkey populations and even caused them to suffer drastic declines in some countries.
New research into the global donkey population indicates that the trade in the animal's skins has exploded to such a level that they face population collapse.
The donkeys were reportedly painted with black and white stripes for a wedding that was taking place at the bar, sparking complaints from animal rights groups in the country.
After animal welfare groups protested the donkeys' maltreatment, the government agreed to impose limits on the duration of a donkey's shift and the weight of its load.
One account said this was the worst animal welfare violation she'd ever seen.
Donkey skins are boiled down to form the basis of a tonic believed to increase sex drive and fight aging in traditional Chinese medicine.