Three puppies dumped in a recycling box in woodland and left to die, were saved when a passing dog sniffed them out and raised the alarm.
The eight-week-old puppies were found shivering in the woods near Bristol on Sunday.
The two males and a female were discovered by a dog being walked in the woods, who ran over to them and kept barking until her owner came over to see what was wrong.
The owner took the puppies to nearby Holly Hedge Animal Sanctuary in Barrow Gurney where they are being looked after.
The puppies - believed to be collie or collie cross breeds - will live in foster homes while they wait to be adopted.
Staff at Holly Hedge have named the trio Tosca, Carlos and Mabel.
Sarah Schranz, kennel and cattery manager for the charity, described what happened as a "a Lassie-style rescue".
"They [the puppies] were in quite an isolated spot where if they had been left for the night they would not have survived.
"They would have struggled to survive in there with no warmth and no mother.
"It beggars belief that in this day and age, with a rescue centre down the road, that someone would leave them there.
"We would never turn away a puppy and they didn't even ask, we had no calls.
"We don't know where they came from. My gut feeling is that these are unsold dogs that were left over from a litter.
"They were going to need vaccinating, worming and flea treatment. They do not have microchips."
Anyone wishing to adopt the puppies should go to Holly Hedge and fill out an application form. Staff at the centre said potential owners should be home most of the time and have a knowledge of active dogs.