Life behind bars can be stressful for lions, but a researcher from UC Davis is trying to put a little pep in a lion family's step.

Veterinarian researcher Sam Counts is trying to find out if music helps calm the mood of lions.

"These are songs you have probably never heard. There is frequencies that only cats can hear in this music," Counts said.

To the human ear, the music sounds like a dull orchestra playing. Sam spends several hours during the week monitoring a lion family at the Sac Zoo. The lion soundtrack is played at random on different days and different times. She documents their behavior throughout the day.

"A study like this would ideally open up the paths to future studies for musical enrichment for animals at the Sac Zoo," Counts said.

It's not clear if the lions "like or dislike" the music. Research will take place throughout the summer.

If you are curious to see the lions' reaction, visit the Sac Zoo. The music plays randomly.