Ore­gon State Police Trooper Anthony Mathews shot the cow dead. And then he had to do it again and again and again."It's heart-wrenching," Mathews said at the scene along Highway 126 west of Walterville, where a truck pulling a trailer with 68 cattle overturned early Tuesday afternoon. "They're more or less like pets, and it's hard, but you have to do what's right for them and not let them suffer." Mathews, a wildlife division trooper with state police, was assigned to kill a total of 12 injured cows trapped inside the trailer.