Can the gray swallows be healed by injury?

The gray swallow foot injury can heal itself.This bird is mainly distributed in the southwestern part of my country. It is more common in Yunnan Province. It likes to live cluster. It usually captures insects in the air. During the reproductive period, mud nests are made on eaves and walls.Its body length is only 18 cm, the upper body is pale gray, with a little sand and brown on the forehead and top of the head. The back neck is gray -brown, the chest is gray, and the abdomen and tail feathers are white.