5.

This puppy was found on the side of the road and brought to the shelter.
The owners put a collar on him when he was much smaller, and never checked it.

Needless to say, the collar got embedded as the puppy grew and when removed, left an open wound all the way around the neck. The pup was taken to the vet and treated for infection and received stitches. This was a lucky pup as one of the staff fell in love and adopted him.