When Puppa, an Italian mastiff, "chased something" down a grassy slope just outside of Brisbane and came back panting, Samantha Egan thought her dog had overheated.
For the day was hot, and the sun was beating.
But Puppa's condition deteriorated quickly, and by the time he had reached the bottom of Flinders Plum Picnic Area he had collapsed.
That's when a terrifying host of symptoms emerged.
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Egan, from Brisbane, wants all pet owners to be aware of the symptoms of snake envenomation, which occurs when the reptile injects venom into a body.
She suspects one of Australia's deadly reptiles was behind her 16-month-old dog's rapid deterioration - and death - just over a week ago.
"He had chased something down a hill and 10 minutes after that he was very stressed, drooling from the mouth and had some blood on his nose and tongue," she told 9news.com.au.
"My partner heard him scuffle with something, but I didn't.
"When he came back we thought he had heat stroke as he was panting.
"We cooled him with water but he shut down.
"Once we got to the bottom of the lookout he lay down, and didn't get back up again."
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Egan rushed Puppa to a 24-hour vet in critical condition.
The vet suspected Puppa could also have heat stroke and the decision was made to euthanise the dog when he showed signs of an incoming heart attack.
"It was going from 40 beats per minutes to 70 beats per minute, similar to cardiac arrest," Egan said.
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It was only after Puppa had been euthanised, Egan found the tiny marks on his tongue.
"We kept asking, 'How could he have died on a 20-minute walk?'
"That's why we looked under his tongue and the whole underside was purple.
"We don't have pictures of that but we have pictures of three purple pin mark bruises."
Egan said the vet has not confirmed these are snake bites, but the owner is confident they are.
The family are devastated, and wish they suspected a snake bite sooner.
"We're not doing great, because we don't have much closure," she said.
"We should have thought it could have been something other than heat stroke.
"I think that it's hard for people to know what has happened when they didn't see a snake.
"The early symptoms are easy to miss, he was down within 20 minutes never to get up again.
What are the signs a pet has been bitten by a snake?
The RSPCA said a snake bite could be likely if a dog displays the following symptoms:
- Sudden weakness followed by collapse
- Shaking or twitching of the muscles and difficulty blinking
- Vomiting
- Loss of bladder and bowel control
- Dilated pupils
- Paralysis
- Blood in urine
Billy Collett, operations manager at the Australian Reptile Park on NSW's Central Coast, said the symptoms of deadly snake envenomation can often be misidentified in pets.
"It's sort of like heat exhaustion; that rapid panting, collapsing, losing consciousness," he told 9news.com.au.
"I've seen a few dogs that have been bitten by snakes and it's pretty nasty.
"A lot die because owners just don't realise they've been bitten."
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Collett's comments come in the midst of "snake season", which typically runs from September and April.
Snake catchers have reported a surge in callouts for venomous hatchlings, which they say is common for late February and early March.
Collett said there are some signs that indicate snakes could be inhabiting a backyard or homes.
"Snake sheddings, poos, slide marks - they are all good signs," he said.
