At first look, it's hard to tell there's anything wrong with Onyx. The black Labrador's coat is shiny and healthy, and his tail wags happily when he runs.

But just five months ago, Onyx was found tied to a wooden pole, with a bloody severed leg. "The night he got here, I didn't think he was going to make it... He was just so dehydrated, septic, his body was in shock because of the infection on his leg," Dr. Daniel Slaton, the L.A. veteranarian who took Onyx in and amputated his leg told WCNC.

Since then, Onyx has quickly recovered. Dr. Slaton adopted him and sent him to The Barkley Pet Hotel and Day Spa where he's been learning how to surf -- yes, surf -- and swim. Onyx, it turns out, has a great sense of balance and can't wait to get in the water!

Swimming isn't the only thing on Onyx's horizon, though. He's also training to become a therapy dog for children with disabilities. Watch the video above the for the whole story.