A media watchdog called on advertisers on Monday to boycott a new television comedy series titled "$#*! My Dad Says," saying the use of this type of language should not be accepted as light hearted fun.

The Parents Television Council (PTC) has written to about 300 companies that advertise on television to complain about the series airing on top-rated TV network CBS that stems from a Twitter account of the same name.

"As an advertiser, you have the power to act upon your corporate values and send a clear message to CBS and its affiliates that this type of profanity in any format has no place in primetime broadcast television," Tim Winter, PTC President, wrote in the letter.

"Associating your company with "Shit" cannot be an effective use of advertising dollars ... I suspect your products are worth more than this raunchy attempt at humor."

He asked advertisers to let the PTC know of their decision by August 15 so that the group could inform its 1.3 million members which companies would continue to be associated with the show.

The program "$#*! My Dad Says" is due to make its CBS debut at 7.30 pm on September 23 starring "Star Trek" actor William Shatner and focuses on a relationship between a cranky older man and his son.

The series is based on a Twitter feed started by struggling comedy writer Justin Halpern in 2003 which captured his own father's salty language and forthright observations.

Called "Shit My Dad Says," Halpern's Twitter feed now has some 1.4 million followers. It has produced a best-selling book of the same name and the CBS TV show involving the creators of the Emmy award winning TV show "Will & Grace."

Bans on "fleeting expletives" in U.S. network broadcasting caused CBS to "bleep" the title. Producers say there are few, if any, profanities in the TV series itself.

But the title has infuriated the Los Angeles-based PTC which was founded in 1995 to highlight children's exposure to sex, violence and profanity on television.

"With no apology, this network broadcast outlet is heavily promoting this program in all day parts in full view of children and unsuspecting parents," Winter wrote.

"Unless or until CBS chooses a different title for this program, we urge you to refrain from sponsoring such an abomination purported to be light hearted fun."

CBS entertainment president Nina Tassler told TV journalists last week -- before the Parents Television Council started its letter campaign -- that there had been no protests so far from advertisers about the upcoming show or its title.

CBS Corp's CBS finished the last season as the most-watched network in the United States for the seventh time in eight years. The series "$#*! My Dad Says" is one of two new comedies being added to its prime time schedule for next season.