The woman said the passerby had "most certainly saved Devo's life" and helped her husband stem the bleeding ahead of a two-hour veterinary operation.
The vet bill cost $1700. Devo still has a gaping hole from the pit bull's teeth.
"The vet has told us Devo was very lucky to keep his leg. It's not like Devo would have done anything to provoke this attack, as he is so meek and mild, he's even afraid of cats," she said.
The woman said dog control staff responded quickly but, in her opinion, their actions since had been less than satisfactory.
It took two days to set a trap, she said, and after the male dog was caught in the trap that night the dog ranger was not strong enough to contain it and the dog escaped, and when the attack dog was caught in the same trap, it also managed to escaped despite two rangers coming to pick it up, she said.
"It's unbelievable this could have happened. I'm not very happy about it," the woman said.
For three days after the attack the dogs returned to her property, and despite council being given an address to check, the dogs remained on the loose, she said.
Devo's owner, who five weeks ago had a baby, said she was too scared to leave the ranchslider open, and feared a further attack when she went out with her baby.
"We are effectively prisoners in our own home," the woman said.
A neighbour had told her she had been intimidated by a dog matching the attack dog's description.
The woman said council needed to be more proactive in locating the dogs before they attack another dog, or even worse, a person.
Mr Lincoln said he could only apologise for the dogs escaping despite the rangers' best efforts to contain them.
"But these breeds of dogs have incredible strength, particularly when caged and approached by strangers. I have instructed staff to take away the whole trap next time," he told the Bay of Plenty Times Weekend.
Mr Lincoln said the delay in setting the trap was due to a staff shortage at the time and he dropped off the trap himself.
Routine patrols in the area had been beefed up since the attack.
A number of properties had been checked without success, and there had been no recent sightings, he said.
"But often dogs are hidden by their owners if they know council staff are looking for them. Rest assured the attack is being treated very seriously and our investigation remains active."
In the past seven months there have been 70 dog attacks on other animals and 34 dog attacks on people within Tauranga City.