Devastated owner Lisa Newberry, a former veterinary nurse, said the dog – which was not muzzled or on a lead – tore into Bertie like a “killing machine”.
Sadly Bertie was put down by a vet who said he would not be able to survive his injuries.
Lisa, 35, of Garston, said: “Bertie was a healthy, strong dog but he was no match for that evil monster.
“It attacked out of nowhere and sunk its jaws into my dog’s neck and shoulder. The owner of the pit bull punched the hell out of it, but the thing did not feel any pain.
“It must have been 10 minutes before they were separated but it was too late for Bertie.
“The family is crippled by grief. I am having terrible flashbacks – I will not be able to get over this as long as I live.
“I rescued Bertie as a puppy. He was not just a dog to me – he was family.”
Bertie underwent extensive surgery after the April 30 attack in King Street and given morphine for the pain. But vets said he would need surgery each week for two months – and it was better to put him to sleep.
Lisa, a full-time mum to son Jake, three, now wants to hunt down the owner of the dangerous dog in a bid for justice. She claimed he fled the scene and refused to give his name.
Lisa said: “I completely blame the owner. He should never have had that killing machine off the lead.
“If the owner has any sort of conscience he will contact the police himself over the attack but I will not give up trying to track him down.
“I am sickened to the very core over what has happened to my faithful loving boy.
“I do not want another family to suffer this pain and torment.”
Police said they had tried to trace the dog’s owner but now regarded the matter as a civil dispute.
Lisa told the ECHO she wants to offer a £200 reward.
The dog owner was in his 50s with a slim build and short hair. The dog, a brown bitch, was said to respond to the name Jade.
The ECHO’s Bite Back campaign has pressed for changes in laws relating to dangerous dogs since 2006.
We have called for all dogs to be microchipped with ownership details.
(Liverpool Echo - May 14, 2012)