'Fear Factor' Contestant Threatened by Show

The honchos over at "Fear Factor" are threatening contestants with possible lawsuits if they dare speak out about the donkey semen contest that NBC refused to air.

Claire Odioso -- one of the contestants who drank a glass of the sperm on the show -- got a threatening call this AM, after execs saw a video of her talking about the stunt posted on our website.

We're told the exec put the kibosh on Claire appearing on TMZ Live today, and further told her if she dared to say another word about animal spunk, they would enforce the confidentiality agreement and sic their lawyers on her.

And we're told ... the other contestants on the show have been warned not to utter a word.