A baby girl successfully underwent surgery to treat a swallowing disorder at Shanxi Provincial Children's Hospital on Tuesday, chinanews.com reported.

Wang Keran, from Zuoquan county, Shanxi province, was unable to chew and swallow food because of a rare disease.

Her single father, Wang Zhihua, chewed food and fed it directly from his mouth to hers. He has been feeding his daughter in this way for more than 500 days.

The impoverished family received donations from across the country to help them cover the girl's medical costs after media reports on their situation.

The baby, who weighed only 7 kilograms when she was first hospitalized, has recovered well and gained 3.5 kilograms over the past three months, her father said.

Chen Rui, the girl's doctor, said the surgery was successful and further nutrition support would be given to enhance the girl's recovery.

The girl has achalasia cardia, which results in the degeneration of the lower esophageal sphincter muscle so swallowed food cannot pass into the esophagus.