it is deadly. the u.s. agriculture department announced that a case of mad cow disease has been confirmed confirmed in a dairy cow out in central california. let s bring in lisa sylvester. she s working this story for us. lisa, what is the department of agriculture saying. what s going on? reporter: wolf, the usda just released information within the last hour and what we know is that it is a dairy cow from central california that has tested positive for bse or commonly known or referred to as mad cow disease, and wolf, this is only the fourth case ever detected in the united states. normally an animal contracts bse from consuming contaminated feed and this cow tested positive from atypical bse, it s a rare form of the disease and not generally associated with an animal-consuming infected feed and it states, quote, the cow was never presented for slaughter for human consumption so at no time presented a risk to the food supply and milk does not transmit bse. so you can se