A keeper holds a giant panda cub at the Bifengxia Base of the China Conservation and Research Center for the Giant Pandas in Ya'an City, southwest China's Sichuan Province, Oct. 13, 2017. The population of captive giant pandas stood at 520 worldwide by Oct. 6, according to the annual conference of the giant panda breeding technology committee of China. (Xinhua/Xue Yubin)