People of Ningxiang, Hunan province, have been raising pigs for more than 1,000 years, and the region's colored pigs are one of the four most famous pig species in China.

The breed is also nicknamed "panda pigs" due to their black and white appearance. They can only be raised in Ningxiang due to its unique weather and water conditions.

The breed nearly went extinct in 2000, as farmers decided raising the species wasn't worthwhile due to its lack of lean meat.

Li Shuchu, president of Hunan Liushahe Hua Zhu Ecological Animal Husbandry Co, said his ancestors were all pig farmers, so he was determined to follow in their footsteps.

He began to rediscover colored pigs in the county in 2003. He and his colleagues found seven boars and 50 sows that year, and he has since been devoted to protecting the breed and raising them on a large scale.

By working with breeding experts, the company has increased the percentage of the pig's lean meat and their breeding capabilities, he said.

It also signed cooperation agreements with high-end supermarkets such as Sam's Club, Hema and Metro AG, Li said. After more than 20 years of hard work, the company now sells about 120,000 pigs every year, with annual sales revenue reaching 300 million ($41 million). It has provided job opportunities for more than 12,000 local farmers, who can earn an extra income of 46,000 yuan per year, he said.

Yin Yulong, a member of the Chinese Academy of Engineering, said raising pigs has been very important for Chinese people since ancient times, as it has served as a key source of protein and income for farmers.

In addition, the feces of the pigs have been used as fertilizer. Fertilizer from pigs is more environmentally friendly than those made by chemicals, he said.

Yin and his team have worked on protecting and improving the breeding of Ningxiang colored pigs for a long time. Through hybridization with foreign pig breeds, his team has increased the lean meat ratio of the pigs, making it more economically appealing for farmers to raise them, he said.

The researchers have also worked to improve the immunity of the pigs with Chinese herb medicine, which has reduced their rate of disease and has helped farmers make better use of the breed's feces, he added.

Gao Jingxia, a doctoral candidate at Hunan Normal University, has lived with 150 colored pigs at a farm in Ningxiang since July to conduct research on how to improve the feed conversion ratio of the pigs.

She did not leave the farm until recently because it must be closed off from the outside world to prevent viruses from spreading. The pigs have been her research subjects and closest "friends" over the past several months, she said, adding that they are very cute and docile.

She put the pigs in the same breeding environment to observe which of them grew fastest, so that researchers can discover the key genes that prompt rapid growth, she said.

She was under quarantine for several days before reentering the farm to continue her studies.

"It is tiring to do the research, but I want to continue and put the research results into actual use, so that the country can have better pig breeds. I am very happy that the research data is very promising for now, and my hard work has paid off," she said.

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