The video, which shows a dachshund named Milo licking the teeth of a 226kg male lion named Bonedigger in an enclosure they cohabit, has had over 350,000 views on YouTube.
Joe Schreibvogel, the owner of the Garold Wayne Interactive Zoological Park in central Oklahoma, introduced his four dachshund puppies to the lion when he was just four weeks old.
Milo and Bonedigger have been inseparable ever since they met five years ago, he says.
Click here to see the video.