When Buddy, an Australian Shepherd, was surrendered to the Hull's Haven Border Collie Rescue in Winnipeg at the beginning of this year, he weighed 180 pounds, or 81 kilograms, and couldn't participate in many day-to-day basic activities that dogs love.

"He could barely walk four or five steps without his tongue turning purple," said Angela Hand, who along with Samantha Gagnon -- both vet technicians -- fostered the animal.

"He couldn't walk very much -- that's a lot of weight on his little legs -- and he was having a really rough time."

The six-year-old pooch's former owners were elderly, and showed their appreciation by keeping him well-fed.

Fearing Buddy would suffer a heart attack, Gagnon and Hand knew that they had to get him back in shape.

Thanks to a strict diet and regular check-ups, the Australian shepherd has undergone a drastic transformation.

Gagnon and Hand kept a close eye on how much specialty food he was eating, and kept treats -- such as cucumbers and tomatoes -- to a minimum.

At first, the progress was slow.

"There were a lot of frequent stops," said Gagnon.

"He would make it like five feet from the deck and he would have to stop."

But every week, his foster parents would take him for weekly check-ins at the Stonewall Vet Clinic where they work.

And after a few months, Buddy had regained his strength and was able to run around with other dogs.

By November, he had lost 45 kg, and required surgery to remove excess skin.

"He had a big lump of skin that would hang down," said Gagnon.

All of these milestones were documented and shared with supporters from across North America on the Facebook page "Buddy's 180 story. A new leash on life."

While Buddy's weight gain was extreme, Hand says that pet obesity is not unusual.

"In the vet clinic, I see a lot of overweight dogs," she said.

"A lot of times people just don't know what they're feeding them, how much they're actually feeding their dog and how much exercise they need."

Now that Buddy is healthy and close to reaching his goal of 30 kg, he is ready for the next step: Finding a loving family to call his own.

Buddy is available for adoption through the Hull's Haven Border Collie Rescue website.