A sea turtle named Omsin, Thai for “piggy bank,” rests after a surgical operation to remove coins from her stomach in Bangkok. (Athit Perawongmetha/Reuters)

The operation took many surgeons and seven hours, much longer than expected, but the team of Thai doctors who cut open then stitched back together the 130-pound green sea turtle in early March walked away convinced they had defeated death.

In a bucket beside them were 915 coins, foreign and domestic, that the 25-year-old creature had swallowed while living in a pond in a seaside town near the Gulf of Thailand. Visitors, longing for good fortune, had plied the water — and by extension the turtle — with lots and lots of money.

By the time rescuers found her nearly drowning, she had swallowed 11 pounds of it.

They named her Omsin, Thai for “piggy bank,” and shared her success with the world.

The coins removed from Omsin’s stomach. (Reuters/Athit Perawongmetha)

For nearly two weeks after the March 6 surgery, veterinary scientist Nantarika Chansue, Thailand’s leading turtle advocate, chronicled Omsin’s progress on Facebook, each post more encouraging than the last. At Veterinary Medical Aquatic Animals Research Center in Bangkok, Omsin received laser therapy on her belly incision, was reintroduced to water in a large kiddie pool and practiced physical therapy for her bum flipper.

Free from the weight of her internal treasures, Omsin could swim again.

“She is getting stronger,” Nantarika wrote on March 9.

“She looks brighter,” the veterinarian added four days later, “probably happier.”

On Friday, after a strict liquid diet, she began eating real food. Her doctors began planning her release into the wild.

Then Saturday, Omsin’s condition deteriorated.

The turtle seemed depressed and irritable, Nantarika wrote on Facebook, with some stomach pain. The vet staff discovered her intestines had become tangled in the hole where her mass once grew. The condition likely developed as her body tried to naturally heal around the gaping space left by the removed coins, reported Khaosod.

“Please keep Piggy Bank in your thoughts,” Nantarika wrote on Facebook. “We got this far… [But] we can’t control what her body does naturally.”

They rushed her into intensive care Sunday night, reported Reuters, and into emergency surgery Monday to untangle her intestines, release pent-up gas and drain fluid from her abdomen.

Her doctors said she slipped into a coma.

On Tuesday, Omsin died.

“At 10:10 a.m., she went with peace,” Nantarika said during a news conference.

She wept, local media reported, and added that Omsin was her “friend, teacher and patient.”

“She at least had the chance to swim freely and eat happily before she passed,” Nantarika said.

Omsin swims in a pool at the Sea Turtle Conservation Center in Bangkok on March 3. (Sakchai Lalit/AP)

The vets said at the news conference that the turtle’s entangled intestines blocked blood flow, causing an acute infection in her intestine that ultimately led to a blood infection, reported Deutsche Welle. The toxicity from the metal coins was 200 times above normal, Nantarika said.

The turtle’s nutritionally deficient diet and stifled environment in captivity may have contributed.

“This led to Piggy Bank being bored,” Nantarika said, “and, eventually, depressed.”

She was supposed to be released to the Royal Thai Navy Turtle pond this week.

Omsin’s story attracted international attention but felt particularly personal to people in Thailand, where turtles are a symbol of longevity. It also became a fable for locals, whom Omsin’s doctors routinely scolded throughout her high-profile recovery for creating the life-threatening environment that eventually took the turtle’s life.

“People believe that throwing coins to these turtles will result in their longevity, so people put them in ponds and throw coins and banknotes at them, causing turtles to die before their natural life span,” Rungrote Thanawongnuwet, head of the Chulalongkorn University vet science program, told Khaosod “This is actually committing sin, not making merit.”

Green sea turtles can live to be 80 years old, he said, but the Thai tradition of tossing coins at turtles to increase their longevity only cuts it shorter.

“I want society to stop using our beliefs to harm animals,” Nantarika said, according to Khaosod. “Animals should have a chance at a natural life.”

Thanawongnuwet told Khaosod that Omsin’s coin-removal surgery was the first of its kind on a green sea turtle. Her case could help inform future attempts to save other turtles from a similar fate and her doctors hope to learn more from an autopsy, reported Reuters.

“She is our teacher,” one vet said.

Omsin’s remains, her doctors said, will be “returned to nature.”

Omsin comes up for air while swimming in a small seawater pool after her operation. (Roberto Schmidt/AFP)

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