Schoep the arthritic dog who warmed the hearts of millions in poignant picture dies after celebrating his 20th birthday

The arthritic dog who became an internet sensation after picture of his owner soothing him in a lake went viral has died a month after he turned 20.

John Unger, owner of Schoep the German Shepherd, announced his pet’s death by posting a photograph of a pawprint in the sand on Facebook with the caption: ‘I breathe but I can’t catch my breath’.

Underneath the picture, which gained 24,000 likes and 49,000 comments within hours, he wrote simply: ‘Schoep passed yesterday.  More information in the days ahead.’

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A touching photo of John Unger and his former dog Schoep shot in Lake Superior reached millions of Internet users in 2012

I breathe but I can’t catch my breath: Schoep’s owner John Unger posted this on Facebook to announce his death

Tens of thousands of people paid tribute to the elderly sheepdog.

Karla Duhart wrote: ‘I will never forget you Schoep.  I am so sorry John’, while Leah Mangue wrote: ‘Your story was inspiring and so heartwarming.

‘All of us should be so lucky and blessed to celebrate a 20th birthday of our canine loves… You were both so lucky to have each other.  Condolences to you.’

The story of loyal dog Schoep, from Wisconsin, became an international sensation when the picture of Unger wading in Lake Superior with him was viewed by millions last year.

Since then, their story has served as the inspiration for a charity called the Schoep Legacy Foundation which has raised more than $25,000 to help low-income families care for their aging dogs thanks to donations from people as far away as Saudi Arabia and Japan.

Mr Unger’s photographer friend Hannah Stonehouse Hudson captured the heartbreaking moment between the man and his aging rescue dog in Wisconsin when Mr Unger realised his best friend was at the end of his life.

Global fans: After an image of Schoep being soothed by his owner went viral, he gained a cult following

The big 2-0: Shoep celebrated his second decade on June 15, surpassing medical expectations

Giving: The Schoep Legacy Foundation has raised more than $25,000 to help low-income families care for their aging dogs thanks to donations from people as far away as Saudi Arabia and Japan

The moving photograph of man and dog in the water inspired strangers to donate to help the dog, which meant that Schoep received the best possible veterinary care in the last few weeks.

So much money came in, Mr Unger and Schoep’s veterinarian, Erik Haukass, decided to put the excess cash to good use.

Dr Haukass said: ‘I’ve never seen anything like this before,’ he said. ‘We realized we had received more money than we would reasonably spend on Schoep’s care.’

Dip: Thanks to the generosity of strangers, Schoep received top-notch care in the last few weeks of his life

Schoep’s owner John Unger took his beloved pet into the lake so that the water could sooth his arthritic pain

Owner Mr Unger, photographer Mrs Hudson, and veterinarian Dr Haukass formed Schoep’s Legacy Foundation

Together with Mr Unger and Mrs Hudson, the three formed Schoep’s Legacy Foundation.

‘The idea is to pay it forward; give it to other organizations, to help out other animals in the area and use the money in the spirit it was given,’ Dr Haukass said.

The elderly dog that touched millions of hearts around the world has died aged 20

The $25,000 will be used in a variety of ways to help low-income families care for their animals, both in the care of older pets and the spaying and neutering of new pets.

‘It could help another 30 or 40 Schoeps,’ Dr Haukass said.

‘It’s incredible to be in a position to help others,’ Mr Unger said.

Mr Unger also said that he’d found himself counseling people who have had to deal with a devastating loss in their lives.

Along with donations, people have been sending Mr Unger their personal stories of woe.

‘They’re going through some depression of their own. They’re very deep and emotional letters. Those are the ones that hit home a lot,’ Mr Unger said.

‘But they look at the picture that Hannah took and it helps them have a better time with it. That’s pretty extraordinary.’

Mr Unger said he credited his dog with getting him through a difficult period of his life.

He and his ex-fiancée adopted Schoep 19 years ago, but when the relationship ended, Mr Unger was on the brink of suicide.

‘To be honest with you, I don’t think I’d be here if I didn’t have Schoep with me (that night). He just snapped me out of it. I don’t know how to explain it. He just snapped me out of it. … I just want to do whatever I can for this dog because he basically saved my ass,’ he said last month.

Beginning: Mr Unger adopted Schoep, who is named after a famous brand of Wisconsin ice cream, when he was just a puppy