



Last summer, a photo of a man cradling his elderly dog in Lake Superior pierced th hearts of millions. Schoep, a shepherd-mix who turned 20 on June 15, passed away on Wednesday, but his image will remain a lasting tribute the deep and loving bond that can run between humans and their animals. Owner John Unger posted a brief Facebook statement on Thursday, "I breathe but I can't catch my breath….Schoep passed yesterday."

More on Yahoo!: Philippine Snout-less Dog Gets Hero's Homecoming

Unger adopted Schoep, who he named after a popular Wisconsin brand of ice cream, when he was eight months old. He told the Daily Mail that the puppy was huddled in the back of his cage and showed signs of abuse. Slowly, Unger and his then-fiancée worked to gain the pup's trust and help build his confidence confidence. Unger's relationship with the dog was mutually giving from the start: when Unger's girlfriend left him, he said he plunged into a suicidal depression, and the pup pulled him out. "To be honest with you, I don't think I'd be here if I didn't have Schoep with me." He told the Mail. "He just snapped me out of it. I don't know how to explain it.… I just want to do whatever I can for this dog because he basically saved my a**."

Watch: Cat Saved With Oxygen Mask

In his final years, Schoep developed painful degenerative arthritis but Unger couldn't afford a regime of daily medication and treatments that cost as much as $200 a session. Instead, he would carry to dog into the lake in the evening to ease his aching joints and help him fall asleep. One night last July, knowing he might have to euthanize his pup in the near future, he asked his friend photographer Hannah Stonehouse Hudson to take one last picture of them together.

The image went viral after she posted it on her Facebook page on August 1, 2012, and received over 2 million hits in a just a week. Then the donations began pouring into Schoep's veterinarian, Dr. Eric Haukass, for his care. "People out of the blue just wanted to donate some money to try and help this dog," Haukaas told the Ashland Daily Press. Eventually, they received tens of thousands of dollars from as far away as Saudi Arabia, and Unger and Haukass established the Schoep's Legacy Foundation to help low income families pay for their pet's medical care. "Literally overnight, I went to bed and the next day when the photo went viral, it was a whole new ballgame for me and for Schoep,'' Unger told TODAY. "It's still overwhelming for me in a sense. I knew the amount that was coming in would be way over the limit that Schoep was going to need for the rest of his life. I just thought, 'I have to give back.'''

In his last year, Schoep received laser treatments and pain medication that reduced the swelling in his joints and allowed him to take walks, go swimming, and rest more comfortably. Earlier this week, Unger posted a photo of Schoep napping peacefully in a meadow of yellow flowers, along with the post, "A fantastic day we had. Up early to walk and go to the beach, eat, nap, go shopping, eat, laundry, go to the beach, eat, nap and one more walk. All without the humidity, that's what made it fantastic- especially for Schoep! (pic) Schoep falling asleep in the sunshine." Rest in peace, good old boy.