Giant panda "Yuan Yuan" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Jia Jia" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

A member of staff interacts with giant pandas at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Jia Jia" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Yuan Yuan" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Qin Kuer" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Yuan Yuan" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Jia Jia" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Qin Kuer" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)

Giant panda "Qin Kuer" plays at the Qinling research center of giant panda breeding in northwest China's Shaanxi Province on March 31, 2020. In 2019, three giant panda cubs "Jia Jia", "Yuan Yuan" and "Qin Kuer" were born in the Qinling research center of giant panda breeding. The three giant pandas grew up healthily with the care of the staff. (Xinhua/Zhang Bowen)