SUPERSIZE MEOW: Waikato SPCA field officer Jessica Watson says Frankie the cat is no longer a fast-food junkie.

A cat who survived for more than a year on McDonald's burgers and fries has been rescued by the SPCA, which says he became so addicted to junk food he initially refused to switch to a more nutritionally balanced diet.

The black-and-white tom, nicknamed "Frankie" by McDonald's staff and patrons in the Hamilton suburb of Frankton, was still a kitten when he was abandoned by departing tenants of a nearby block of flats.

The hungry stray took up residence in the fast-food restaurant's carpark, where he would beg for the odd chicken nugget or hunk of beef patty from cars as they came through the drive-through.

But living rough - and a diet of fast food - took its toll, and in recent weeks McDonald's workers and members became concerned that Frankie's health was deteriorating.

That's when Jessica Watson, a field officer with the Waikato SPCA and regular McDonald's customer, spotted Frankie and took him into her care. She is now looking for a family to adopt him.

"I estimate he has lived in the McDonald's carpark for 12 to 18 months," said Watson.

"Everyone knew to keep an eye out for him. You would go through the drive-through and ask for a burger for you and an extra patty for Frankie.

"He would watch you and trot after the car, wait until you stopped the car and then you would toss him the meat. It was his little routine."

Watson said she grew worried when she saw Frankie's face was swollen, his eyelids weren't closing properly and his coat was matted.

But after a couple of weeks of inside living and good nutrition he is now clear-eyed and shiny-coated.

"He wasn't overweight," said Watson, "but McDonald's wouldn't meet the nutritional requirements for a cat.

"They need very high levels of protein and I wouldn't think takeaways would provide that."

It took a while to wean the Maccas-addicted Frankie off his junk food of choice.

"When I first took him home he refused to eat anything because it wasn't McDonald's," said Watson.

"I seriously considered going back there to get him a burger.

"I would put pet food down and he would give me a look like, 'What is that?' "

After a couple of days, though, Frankie came to his senses and now enjoys a more traditional diet of water and cat biscuits - no fries, no soft-drinks, and no super-sizing, despite his requests for seconds.

"He's a big, and healthy, eater," said Watson.

There was one benefit to the McDonald's diet though, said Watson.

She's pretty sure that, unlike some cats, Frankie won't have been tempted to predate any endangered native bird species during his days as a stray.

"I'd say he loved cheeseburgers far too much to worry about any birds."

Since Frankie's story hit the headlines. the SPCA has had so many inquiries that would-be adopters are being asked to report in person to the SPCA offices, where they can complete an "expression of interest" form before staff choose his new family.

- Additional reporting Angela Cuming