CHONGQING -- Twin panda brothers born in a zoo in Southwest China's Chongqing municipality started to receive public visitors on Friday.

A female panda named "Mangzai" gave birth to them on June 10. "Giant pandas often only choose the stronger one of the twins to feed," said Yin Yanqiang, technical director taking care of the animals at Chongqing Zoo.

"To ensure the survival of the two, we carried out artificially assisted feeding, with one brought up by the panda mom and the other artificially raised in the nursery box. We exchanged their places regularly to allow both of them to enjoy the breast milk in time," Yin said.

The brothers are growing well with concerted efforts. The older cub now weighs 6,060 grams and the younger one 5,680 grams, said Yin, adding that the twins have different personalities. "The older brother is more active and alert, while the younger cub gentler and quieter."

The nursery receives visits in two timeslots from Friday, 10:00-11:00 am and 2:30-3:30 pm, and the public is invited to give names for the cubs.