For centuries, in rural cultures across the globe, one animal has been an important part of the family, helping to keep farms and villages running.

Not only do millions of people depend on donkeys for practical purposes — many donkeys are seen more and more as smart and loyal pets.

cute donkeyShutterstock

But this friendship between people and donkeys is increasingly threatened by a growing trade in something you've probably never even heard of: "ejiao," (also known as "colla corii asini" or "donkey hide glue") a kind of gelatin made from donkey skin — and demand for ejiao is killing literally millions of donkeys per year.

Warning: Graphic content below

donkey skin ejiao factory hong kongAn ejiao production factory in Hong KongGeorge Knowles

A new report from The Donkey Sanctuary in the U.K. shows just how massive this emerging global trade really is. At least 1.8 million donkey skins are being traded each year — but it could be between 4 million and 10 million. The trade is difficult to track and until now hasn't been studied at such a large scale.

donkey skin ejiao products being sold in Hong KongEjiao products being sold in Hong KongGeorge Knowles

"Our report reveals the shocking scale of this global trade and how it's causing a chain of welfare issues for the donkeys at every step, from sourcing to transport and finally to slaughter," Mike Baker, chief executive of The Donkey Sanctuary, told The Dodo in a statement.

donkeys packed in pen in tanzaniaDonkeys packed tightly in a pen in TanzaniaThe Donkey Sanctuary

"Ejiao is a medicine with ancient roots and has been promoted as a product worthy of emperors," the report says, explaining that traditional herbalists in China claim that ejiao can increase libido, slow aging and prevent disease. But ejiao has not been recognized as having medicinal properties by western medicine.

donkey skin trade chinaDonkey skins outside an ejiao factory in Hong KongGeorge Knowles

This belief means that donkeys are becoming more valuable for their skins, and therefore harder for rural families to afford. Even the loyal donkeys families already have are at risk. It is becoming more common for donkeys to be stolen right out of a family's yard and slaughtered for their skins.

in Tanzania village 24 donkeys were stolen and killed for the skin tradeIn a village in Tanzania, 24 donkeys were stolen and killed for their skins. MAWO Tanzania

While exports of donkey skins come from South America and Asia, the largest source is in Africa, where donkeys (many of them stolen) are rounded up in "donkey markets," where they are often packed together and left without shelter from the hot sun and without food or water, while they await slaughter.

Often, after the skins are removed, the bodies of the donkeys are burned.

donkey skin trade carcasses burningDonkey carcasses burning outside a legal slaughterhouse in TanzaniaThe Donkey Sanctuary

"The market is far worse than I expected," said Alex Mayers, program manager at The Donkey Sanctuary, from a donkey market in Tanzania last week. "There are about 700 donkeys basically coming here to wait to die. There's no food or water. The donkeys are very stressed. There are lots of signs of dehydration and hunger."

But there is hope.

donkey holding pen tanzaniaAlex Mayers of The Donkey Sanctuary pets a donkey in a holding pen in Tanzania.The Donkey Sanctuary

Some countries have already taken action and banned exports of donkey skins, making their donkeys much safer. This includes the African countries of Niger and Burkina Faso, and Pakistan, in Asia.

The Donkey Sanctuary is calling for a stop to the trade of donkey skins worldwide, so that the damage already done to donkey populations and the people who depend on them can be assessed.

tanzania family and donkeyA family and their donkey in Northern TanzaniaThe Donkey Sanctuary

"In particular, we urge other countries affected by this trade to follow the lead taken by Burkina Faso and Niger and ban the slaughter and export of donkeys for their skins," Suzi Cretney, public relations manager for The Donkey Sanctuary, told The Dodo.

Cretney said that raising public awareness about where ejiao really comes from could help consumers make better choices.

donkey skin trade mapThe Donkey Sanctuary

"We are asking countries to follow the lead by Burkina Faso and Niger to end the slaughter and export of donkeys for their skins because it could help thousands, if not millions of donkeys — their welfare, and their real value supporting people's livelihoods is at risk," Baker said.

"This has to stop," Mayers said, standing by a pen packed with donkeys awaiting their fate. "This absolutely just has to stop."

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