US | mysterious animal deaths Here's What Killed Those Dead Cows Toxic sweet potatoes were included in their feed By Evann Gastaldo Posted Jan 31, 2011 1:38 PM CST Copied The cows were done in by sweet potatoes. (?karlfrankowski) The latest mass animal death mystery has been solved: The 200 cows that dropped dead in a Wisconsin pasture two weeks ago were killed by, of all things, moldy sweet potatoes. The farmer who owned them originally suspected disease, but investigators ruled that out and determined the cows were likely poisoned by the spoiled sweet potatoes, which were included in their feed, Aol News reports. Click here for more. Read These Next Saudi tells Iran to wise up, 'stop attacking their neighbors.' Ex-counterterror official Joe Kent is under investigation by the FBI. Israel's 'decapitation' strategy in Iran carries risks. Democrats walk out on Bondi's Epstein files briefing. Report an error