Founded in 1952, the Dongeejiao plant is a two-hour drive from Jinan, the capital of Shandong province. [Photo by Yang Feiyue/China Daily]

A tourist town, a museum and donkey ranch greet us when we reach Dongeejiao－also the name of a time-honored brand－after a two-hour drive from Jinan, the capital of Shandong province, in early September.

Dongeejiao, which makes donkey-hide gelatin, was once a household name.

The gelatin is a traditional Chinese tonic that is one of the three treasures, along with ginseng and pilos antler, in the bible of traditional Chinese medicine, the Compendium Of Materia Medica.

The gelatin is believed to help in treating blood deficiency, insomnia and lung diseases.

The Dongeejiao plant was founded in 1952 but the brand suffered a decline over the years thanks to fewer animals.

But now, hybrid black donkeys with oily skin roll on the ground at the plant's ranch, as the company has a new lease of life thanks to a plentiful supply of the animal.

The black donkey features a thick skin, says Li Mengqi, a tour guide with Dongeejiao.

Also, the height of the hybrids is 15 percent more as compared with the other animals, while the weight and hide is 30 percent more.

The feeding cycle for the hybrids is also shorter by three to six months, which means a 35-percent benefit for the company.

The number of donkeys in China is now 6 million and rising, according to the national animal husbandry authority.

But China used to have 9.4 million over 1996-2012, before the decline set in and affected gelatin output.

So, to ensure a steady supply of donkeys, Dongeejiao set up a total of 20 black donkey breeding sites across the country.

As donkeys do not reproduce as frequently, artificial insemination is resorted to, says Li.

"We manually collect sperm and preserve it in diluted yolk with liquid nitrogen.

"The sperm can be preserved for 10 years like this."

As of now, the ranch at Dongeejiao has 108 males, and each donkey produces enough sperm to ensure the birth of 800-1,000 donkeys a year.