I would be very careful when buying bulk corn that has not been certified toxin free (20 PPM). Lot of rejected unacceptable corn is marketed this way.
Also make sure your bagged corn has the USDA certified toxin free tag sewn in top of bag.
Bury your rotten clean out, left over old corn (for the hogs to eat) or burn it. Hogs can tolerate a lot of toxin where birds and game animals can't
“In Texas, there are two important mycotoxins on crops—aflatoxin and fumonisin. Aflatoxin is usually associated with corn, cottonseed and peanuts. Fumonisin is commonly associated with corn,” he said. “Environmental conditions, such as drought, excessive moisture at a critical growth period, or insect damage, will determine the occurrence of these toxins, which can be deadly for livestock at certain levels.”http://www.hpj.com/crops/emergency-meeti...f280a47c30.html