John Tombs was walking six-year-old Lady in Osmaston Park when a Staffordshire Bull Terrier ran up to her and locked its jaw round her throat.
The attack left her with injuries which meant she could not swallow or breathe while lying down.
Two days after the attack, John and wife Joyce made the tough decision to put her to sleep.
John, of Marlborough Road, Allenton, said: "Lady was just so full of life and very affectionate. She was there for us all the time.
"She was only a small dog but has left a big hole in our lives.
"When we came in the front door, she'd bounce up to us wagging her tail.
"It's heartbreaking. My wife still gets upset about it."
John had taken Lady out on her regular evening walk to Osmaston Park on December 14.
He said that when the tan-coloured Staffordshire Bull Terrier ran up to them, Lady looked as though she wanted to play with it.
But he added that almost immediately, the dog started attacking her.
John said the dog's owner, a man in his 30s of medium-to-large build, did not try to get his dog off Lady.
John said: "I was trying to pull this dog off but he was standing there saying, 'No, no, no'."
John rushed Lady to St Leonard Veterinary Centre, in Osmaston Road, where she was referred to Pride Animal Hospital, in Pride Park.
"They were brilliant. You couldn't ask for a better vet," said John.
"Now there are two questions I would ask the owner of the Staffy.
"You must have known it was a vicious animal, so why did you allow it to roam in a dark park off its lead?
"And the other thing that worries me, and possibly should you as well, is that I noticed you had a little girl aged about three years old with you.
"She could be the dog's next victim."
He added that since she died, dog walkers who used to see Lady regularly have been upset about the news.
"She was a popular dog," he said.
(Derby Telegraph - January 07, 2012)
