Rio gave birth to nine puppies but one -- with fur like a stick of wintergreen gum -- stuck out.

Louise Sutherland named the puppy Forest.

"It was all hands on deck but then as the puppies started to arrive, we noticed that one of the puppies had green fur," Sutherland told the Daily Mail. "We couldn't believe it."

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The rare discoloration is caused when a bile pigment, billiverdin, mixes with the mother’s amniotic fluid.

Sutherland said the color has already started to fade and is expected to be completely gone.

This was Rio’s second, and final, litter, Sutherland said.

All the puppies have gone to good homes in the past, Sutherland said, but she is going to keep Forest.