The sale of a cat skin in an online auction site has sparked an investigation in New Zealand.

New Zealand's Society for the Prevention of Cruelty to Animals (SPCA) said the online auction, which happened on the Trade Me site, was deeply offensive.

Gavin Wilkinson from Auckland placed on Trade Me an auction for a "beautifully marked wild cat skin." It sold on Thursday to a winning bid of $NZ70 ($A59).

"We will investigate this case to determine whether there has been a breach of the Animal Welfare Act," Bob Kerridge, SPCA National President, said over the weekend.

He said the auction was disturbing none of Mr Wilkinson's description noted if the skin came from a feral, stray or companion cat.

"In New Zealand, we have three groups of cats - companion cats, stray cats, and feral cats - but they all belong to the same species," Mr Kerridge explained.

"The only difference between them is the amount of contact they have with humans."

But Mr Wilkinson did day in his auction description that he caught the animal eight months ago, "eating my chickens, pheasants and who knows what else!" He even accompanied his online sale with a photo showing the damage.

"I find there's a lot of ignorance in people, with cats, they don't actually realise what sort of damage they do. I've had first-hand experience with feral cats and I don't think people realise the damage these cats do to the environment," he told One News.

However, under NZ's Animal Welfare Act, even stray cats have rights, thus also protected.

"The question is: how can you tell whether a skin for sale on Trade Me came from a feral cat, a cat that was simply a stray, or someone's beloved companion cat? The answer is: you can't."

"So if this cat was killed in an inhumane way, charges could be laid," Mr Kerridge said.

Mr Wilkinson said used the method recommended by the Department of Conservation to kill and skin the cat.

According to AAP, a stuffed roadkill cat sold for nearly $1000 earlier this year in another Trade Me auction.

Debate and Protest

The cat skin auction brought off a series of debate and protest right on Mr Wilkinson's Trade Me site.

Some read as follows:

"Good for you! We recently had something eat 3 of our new born piglets so set a cage and caught a large healthy ...now dead ...wildcat."

"Did you know the people kill more birds than cats each year. How many have you killed with your car?? Maybe skin yourself once this auction has finished, since you kill birds also! Your listing will be remove by TM come hell or high water. Better hope and pray that was not someone pet you killed."

"LOL....nice one..... We need more people doing this.... has my vote!!"

"I'd like to see your skin on the wall!"