Six dogs — one dead and one clinging to life — got sick after having contact with the St. Lucie River, which is polluted with toxic blue-green algae blooms in some areas.

"All of them had been in the river and all had the same symptoms," said Cristina Maldonado, a Stuart veterinarian who treated one dog and has talked with most of the other dogs' owners. "It can't be a coincidence."

All the dogs suffered serious liver damage and had internal bleeding. Most received plasma transfusions to help their blood clot so they wouldn't bleed to death.

Symptoms included vomiting and diarrhea within a few hours of contact with the water, followed by lethargy. The dog that died started shaking and lay down, "then he went limp, completely limp," Misty Aydelotte said of Finn, her 9-year-old standard poodle.

"A blood test showed Finn had a belly full of blood," Aydelotte said.

Those are "classic signs of cyanobacteria toxicity," Maldonado said, using the scientific term for blue-green algae.

Owners of dogs with similar symptoms should tell veterinarians immediately if their pets has been in the river, Maldonado said.

Some of the sick dogs' owners think their pets drank algae-tainted water; a couple suspect their dogs ate algae-covered dead fish found along the riverbank.

Sick dogs

Finn died Wednesday within 48 hours of getting in the river near the family's Rio home.

Sammy, a 7-year-old golden retriever owned by Karin and Rob Torsiello, was in serious condition in a veterinary clinic Monday, three days after she got in the river's North Fork near their Palm City home.

The Torsiellos' other golden retriever, 2-year-old Savvy, got in the water with Sammy and got sick, but not as seriously.

The other dogs apparently sickened by the algae are:

Stanley, a Chihuahua mix believed to be about 5 years old owned by Diane Arasa, who lives on the river in Stuart

Pandora, a 2-year-old miniature Pomeranian, who had contact with the water near owner Becky Harris' riverfront home in Stuart

Costa, a 4-year-old golden retriever who got in the river near owner Ashley Guzi's home in the Rio community

Owners said their dogs escaped their watchful eye and headed for the river, two through gates someone forgot to latch.

In most cases, owners reported little or no visible algae where their dogs were recovered. There was a "neon green" bloom in the river behind Karin Torsiello's house two weeks ago, "but it was gone in a couple of days," she said.

"I guess the message is: Even if you don't see it, there's dangerous algae in the water," she said. "Just don't let your dog in the water."

Medical tests

Maldonado, who is treating Costa, said she's got more questions about the rash of illnesses than answers.

"If the algae is to blame, why don't we have any dead shorebirds or manatees or dolphins like we did during algae blooms in 2016?" she asked. "Why were there no sick dogs earlier this summer when there was more algae in the river? Why are they showing up now, when it looks like the algae has dissipated?"

For answers, Maldonado is paying to have samples of Finn's vomit and liver sent to Brain Chemistry Labs in Jackson Hole, Wyoming, to test for the presence of microcystin, a toxin often found in blue-green algae.

Microcystin can cause nausea and vomiting if ingested, rashes and hay fever symptoms if touched or inhaled. Drinking water with the toxin can lead to long-term liver disease.

The lab will test samples from Finn's brain for the presence of BMAA, another toxin found in blue-green algae some researchers believe can trigger neuro-degenerative diseases such as Alzheimer's, Parkinson's and amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's Disease.

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