A staff member scans the microchip implanted under the skin of a pet dog in Guangzhou, capital of south China's Guangdong Province, May 16, 2011. Guangzhou started to implant microchips to pet dogs in the city on Monday. The microchip is much useful in the return of lost pet dogs and data management on pets' register, medical care and identification. [Xinhua/Lu Hanxin]