The poodle was found in Sembawang on New Year's Day this year, emaciated and weak.
It had severely infected wounds and maggots were festering everywhere, even in the roof of its mouth.
Despite having a collar and microchip, its owner could not be ascertained.
This is a problem that animal groups have been grappling with.
When a dog is sold, the shop must apply for the licence on behalf of the buyer and register the dog's microchip number with the Agri-Food & Veterinary Authority (AVA). This is stated on the AVA website.
Microchips are not embedded with any identifiable information. Without registration, they amount to little more than meaningless strings of numbers.
In a undercover survey done by the Society for Prevention of Cruelty to Animals (SPCA) in 2012, most pet shops and retailers did not help with licencing.
Shops blamed this on owners' reluctance to disclose information, often pretending to buy the dogs for "someone else".
Mr Ricky Yeo, president of Action for Singapore Dogs (ASD), told The New Paper last year: "There are still many cases of lost dogs without adequate information to track the owner.
"It is extremely frustrating to handle cases where we have a microchip number but no owner details."
According to SPCA, out of over 1,000 dogs it took in last year, 275 were considered lost or were left by their owners at SPCA. In 2012, the number was 393.
SPCA stresses that the drop did not mean that fewer Singaporeans are abandoning their pets overall.
ASD says the number of stray and abandoned dogs has been increasing by 20 to 30 per cent each year.
In the case of the Sembawang pup, volunteers from Save Our Street Dogs (SOSD) took it in.
A spokesman says they removed more than 100 maggots from it.
After two weeks of veterinary treatment, including multiple wound cleansing, the dog was discharged.
And there is a happily-ever-after ending, too.
A few weeks ago, the dog, nicknamed "Margot", was adopted by National University of Singapore student Sabrina Tang, 21. She has since renamed the dog "Marcel".
Miss Tang says she knew about Marcel through SOSD's Facebook page. The animal lover used to have a dog for nine years before it died.
"I finally felt that it was appropriate to get another dog and I am mature enough to know his needs and handle his training," she says.
Despite her family's initial uncertainty about Marcel, its story won them over. They even offered to assist SOSD with the medical fees.
Although some dogs like Marcel get a new life in loving homes, the rest of the lost and abandoned animals are not as lucky.
Taro, another dog rescued by SOSD last November, was found with a huge maggot wound that exposed its skull.
After emergency treatment and a blood transfusion, Taro is out of danger. But as of today, it has yet to find a permanent home.
To know more about Taro's journey, go to tinyurl.com/tarodog
Miss Tang says: "Adopting a full-grown dog with a past is a rewarding experience when you see the fear and pain disappear."
Although she does not know how Marcel's injuries got so bad, she is not interested in meeting its previous owners.
"I'm not sure what I would say to them if we met, but I'd be happier not meeting them."
Register your pet
Microchip registration can be done with the Agri-Food & Veterinary Authority (AVA) when owners register for or renew their dog licenses.
Pet owners can also register with Pet-Call, a privately-run database, on its website (petcall.org). It accepts registrations for dogs, cats and other microchipped animals.
This article was published on April 13 in The New Paper.Get The New Paper for more stories.