Maya died over the weekend at the National Aquarium in Baltimore after suffering an illness off and on over the past few months. (Jay P Fleming/National Aquarium)

An 18-year-old dolphin named Maya has been euthanized at the National Aquarium in Baltimore after several months of being ill, officials said.

Officials at the aquarium said in a statement that Maya first started to show “signs of illness” and a loss of appetite in March. Experts at the aquarium said she was given “round-the-clock care,” along with antibiotics, electrolytes and vitamins.

Maya was one of seven dolphins at the aquarium.

At first, she showed some signs of getting better. But in mid-April some other health problems arose.

Veterinarians found she had “inflammation throughout her body and her liver was not functioning properly, causing issues within her digestive system.”

Maya was put through tests and a biopsy was done on her liver. Officials at the aquarium said they also consulted with mammal experts “all over the country to help diagnose and treat her,” according to a statement.

During the weekend, her health “declined rapidly.” The aquarium staff said she became “very lethargic” and had abnormal breathing and was “unable to keep any food down.” They said her “breathing was elevated.”

Officials said “despite our best efforts to help her over this long period of illness, Maya was unfortunately unable to recover.” Aquarium staff euthanized her Sunday so that “she did not endure any additional pain or suffering.”

A necropsy will be done, officials said.

The aquarium’s other dolphins are in “good health at this time,” officials said. But aquarium officials said “dolphins are known to grieve the loss of members of their colony and will therefore be given time and support as they adjust to life without Maya.”

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Maya was the third oldest of the dolphins at the aquarium. She was an Atlantic bottlenose dolphin, which get their names from their short beaks.

Adult-size dolphins can weigh anywhere between 400 and 800 pounds and grow up to 12 feet long. They’re found around the world in tropical areas and along bays, coastlines or harbors. Typically, dolphins in captivity live between 35 and 40 years. In the wild, they live anywhere from 30 to 50 years, experts said.

In a statement, officials at the facility said, Maya “inspired the Aquarium’s dedicated staff and volunteers, who loved her dearly. She not only enriched the lives of her Aquarium family, but educated and inspired millions of Aquarium members, guests and school groups.”