More than 20 animal protection organizations called for authorities on Monday to strengthen the quarantine of dogs and cats and crack down on the underground dog theft and slaughter network to secure food safety and build a national civic image.

The campaign precedes the dog meat festival in Yulin, Guangxi Zhuang Autonomous Region on June 21, where the signature dish features dog meat cooked with lychees.

"Stolen dogs without quarantine certificates are cruelly slaughtered and sold to restaurants at very low prices," said Master Huici, assistant director of the Hebei Buddhism Charity Foundation, who went to Yulin to investigate the dog trade.

Animal protection activists around the country have helped intercept several trucks stuffed with dogs in recent years, trying to prevent stolen dogs from being sent to illegal slaughter houses to be sold as food.

These actions prompted the Ministry of Agriculture to issue a circular on April 22, requesting local governments to strengthen cat and dog quarantine at the origin to control diseases that can be transmitted from animal to human, said Liu Lang, president of the Beijing Small Animal Veterinary Association, who helped draft the circular.

"The regulation requires one-by-one lab quarantine for cats and dogs before transportation, which is costly and followed by serious punishment for violations. It prevents illegal trading if it's strictly applied," Liu told the Global Times.

A complex underground dog theft and slaughter network was revealed in recent years with three major bases in Jilin, Guangdong and Jiangsu provinces, where dogs are stolen from rural households and transported to illegal purchasing stations, said Guo Peng, a professor of animal protection with Shandong University.

"They kill guard dogs with poison or knock them down, and collect dead, sick or homeless dogs to sell meat to processors, which is a huge food safety risk and threatens rural residents' security," said Guo. 

Eating dog meat, while traditional in some areas, such as among the Korean ethic minority, who mainly live in Northeast China's Jilin Province, has become more controversial.

"Traditions should be reviewed and revised as civilization develops, as cruel dog slaughtering and eating are against animal ethics and harming our national image," said Jiang Jinsong, professor with Tsinghua University.

Currently, Jilin has the only dog meat quarantine regulation in the country, and there is no national regulation to distinguish between legal and illegal dog meat products, which creates loopholes to develop the underground trade, as artificial breeding of dogs is far below the market demand, said Guo.

The organizations also sent open letters to provincial governments in Jilin, Jiangsu and Guangdong Monday, calling on them to strengthen quarantine supervision and limit cross-regional transportation.

Another letter was sent to Yulin city government, asking them to cancel the festival. A planned dog meat festival in Jinhua, Zhejiang Province in 2011 was canceled following intense public criticism.