A giant panda cub rests on a tree at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub climbs a tree at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub rests on a tree at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub eats bamboo shoots at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub eats bamboo shoots at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub is seen at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub eats bamboo shoots at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A giant panda cub eats bamboo shoots at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

 A feeder holds a giant panda cub at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)

A feeder holds a giant panda cub at the Bifengxia Base of China Giant Panda Protection and Research Center in Ya'an City, southwest China's Sichuan Province, June 10, 2014. A special "kindergarten" was set up at the base for giant panda cubs, and now six cubs born last year lived here. (Xinhua/Xue Yubin)