CINCINNATI -- There's a very good reason to cuddle a baby hippo.
Fiona, born six weeks premature and far underweight at the Cincinnati Zoo and Botanical Garden, was in stable condition Saturday.
Keepers are trying to regulate her oxygen intake, so they're holding her chest to chest so she can feel normal breathing.
Fiona's lungs absorb carbon dioxide when she holds her breath, a natural reflex for when hippos go underwater. This causes her oxygen levels to dip.
GALLERY: Meet Cincinnati Zoo's baby hippo
The zoo announced Friday she was being given milk via a feeding tube because her energy was low, and because she continued to have a weak suckling response.
An animal care team is working with Fiona around the clock, including trying to help her stand and learn to swim using pool noodles.
Vets determined that she was too weak to stand to nurse from mom, Bibi, when she arrived early. She is being cared for in close proximity to mom and dad, Henry, so they can hear and smell each other, zoo officials said.
Fiona weighed 29 pounds when she was born, which is about 25 pounds lighter than the lowest recorded birth weight for this species. The normal range is 55 to 120 pounds.