A 32-year-old elephant residing at Zoo Miami is said to be in grave condition and his prognosis is not good.

Machito, one of the zoo's African elephants, is being watched around the clock as veterinarians attempt to diagnose what is ailing him.

The elephant's health has declined over the last few weeks and tests given to determine whether Machito suffers from pneumonia or heart disease have not yielded a positive response.

Machito's condition has deteriorated so much over the last 48 hours that the zoo staff has begun giving him pain medication to keep him comfortable.