File in the bulging folder of Really Bad Ideas: It's estimated that as much as 2 billion pounds of poultry litter (comprising chicken manure aka poop, feathers, spilled feed, bedding material, dead rodents, etc.) are fed to cattle every year. That's more than just gross — it courts mad cow disease, reports Consumers Union, as "material from cows—meat and bone meal—can be ground up and put in chicken feed. Since poultry litter can contain spilled feed, this means material from cows can be indirectly fed back to cows via poultry litter." As could a number of antibiotics and other drugs that can be legally fed to poultry, but which could be toxic to cattle. (Not In My Food Blog/Consumers Union) Take action: Help stop the practice — which used to be banned before the FDA revoked it to allow states to regulate (or not) — by signing this CU-backed petition. Because if you think the government's got your back (or your brain) when it comes to mad-cow testing, don't be so sure.