Dozens of dead cows - no blood, no gunshots - mystify ranchers Ranchers in Chino Valley dug trenches Wednesday afternoon to bury dozens of dead cows. "Whatever killed them killed them fairly quick" Tom Silva lives in the area and traps small animals for a living. He wanted to see what all the commotion was about. "There's no struggle. When an animal dies it sometimes struggles, it's legs move but these animals just look like they dropped over." No blood. No gunshots. No one knows exactly killed these beasts. "Has to be some kind of poison, I mean, to kill this many and not have any signs of struggle it must be a very toxic kind of poison." The Department of Agriculture was called to the scene to investigate. A vet from their Arizona Livestock Incident Response Team took samples from the animals....