Hip-hop impresario Russell Simmons (search) has joined other celebrities and activists who have criticized Kentucky Fried Chicken (search), saying he will call for a boycott if the company doesn't reform its slaughter practices.

Simmons called slaughter practices used by the fast-food chain's suppliers "grossly inhumane" and has filmed a commercial "showing some of the very worst abuses chickens undergo" before they are served to customers, the Daily News reported Sunday.

Simmons, who is chairman of Def Jam Records (search) and is a vegan, said he has talked to officials of Yum! Brands, the parent company of KFC, and said he will release the ad and start a boycott if the company does not reform its practices.

"When a company targets our community, disrespects us as consumers and sells us products ridden with negative energy and laced with toxins, that is our business," said Simmons.

Other celebrities and activists who have raised their voices against KFC include the Rev. Al Sharpton, comedian and social activist Dick Gregory, actress Pamela Anderson and musician Paul McCartney.

Yum! Brands Vice President Jonathan Blum disputed Simmons' claim.

"We have an independent panel of outside experts who set our high standards," said Blum. "They are the same standards that all our competitors use to insure human treatment around the country."