THE advertising watchdog receives many complaints from the public. Some are justified, some are questionable.

Some are a bit ridiculous.

Telstra has been forced to defend the treatment of a pet cat in a video filmed more than 20 years ago that it featured in one of its TV ads.

The company decided to include the popular "Keyboard Cat" video clip in one of its ads for the T-Hub phone earlier this year.

The YouTube video, which has been viewed more than 8 million times, shows Fatso the cat appearing to play a simple melody on a keyboard.

But while he might delight bloggers, Fatso has rubbed at least one TV viewer the wrong way.

After seeing Telstra's ad, one animal lover made an official complaint to the Advertising Standards Bureau (ASB) alleging that it was cruel.

"The cat is clearly being forced to play this piano does not appear to be comfortable and quite frankly I think it's cruel to depict a living animal being treated like a puppet," said the complainant.

Telstra disputed the allegation, saying Fatso appeared to be "at ease" and "laid back".

The company added: "It is very difficult to make a cat do anything it does not like without an obvious struggle."

The bureau dismissed the complaint, saying in a case report that it "considered that most members of the community would consider the depiction of the cat playing the piano as humorous".

ASB boss Fiona Jolly told news.com.au the complaint had been the only one received about the Telstra ad.

"Australia’s self-regulation system allows for the diversity of cultures, beliefs and lifestyles of the Australian community," she said.

"With such a diverse community, we expect to get wide ranging views expressed in the complaints we receive."

Telstra said it had no comment beyond those published in the case report.

Keyboard Cat is the basis of an internet joke that sees Fatso "play off" people in other YouTube videos who have done something embarrassing.

The clip was originally filmed in 1984 by Fatso's owner Charlie Schmidt, who manipulated the cat's legs to make it appear he was playing the keyboard.

It was then uploaded to YouTube in 2007, where it became popular.

Fatso reportedly passed away in 2000.

Watch the Telstra ad below: