The male African lion that has called Como Zoo its home throughout its life has died at the age of 17.

The male lion, Mufasa, had to be euthanized "due to declining health and advanced age," the St. Paul zoo said, with the decision taken when he no longer responded to treatments.

The zoo said in its announcement that it's "heartbroken to have to say goodbye," adding: "These decisions are never easy and are made after exhaustive discussions between the veterinary staff and Como’s animal care staff."

Mufasa, one of the most popular animals at the zoo, had been undergoing treatment for thrombocytopenia, a condition that causes low blood platelets and "difficulty clotting."

It comes four years after the death of Mufasa's mother, Wynona, at the age of 22. At the time of her death, she was the second-oldest lion in captivity in the U.S.

She had lived at the zoo since six months old and gave birth to 12 cubs, among them Mufasa and Savannah, the lioness who is still at the zoo.