On Thursday two chickens were dead in the chicken yard. One had no head. The head was found in the chicken house. Today two chickens were found dead, one in the house without a head and the other in the yard without a head. We do have rats. I wonder if the rats killed the chickens, or did the chickens die of something else, and the rats just ate the head? There was no sign of a fight and no previous symptoms signaling they might be ill. Our chicken yard is secure from large predators. Nothing larger than a raccoon could enter. The rats have in the past stashed their left over food in the chicken house. BTW I live in Northwest Washington.