No tail?

So I am working on placing the last of a breeding herd. I have 30 Chins left to find homes for. Well out of the 10 I am fostering now one female is missing a tail. She has no tail not even a nub and she is missing an ear and half of the other ear. She is so nice and gets along with almost any chin you put in with her.

I can understand how a chins could lose it's ears but a tail? That is so much most a part of the body. It is part of the back with bones. Can they be born that way? Or was it chewed off when she was a baby?