My 10 month old Cochin died yesterday. Around 4:00 we let our chickens out to get some exercise. Pepe' looked and acted normal in all aspects. About 45 minutes later she was sitting down behind the coop. My DH thought the rooster had been chasing her and she was just hiding from him. He held her until I finished the chicken chores then we put her in the nest box. We went into the house around 5:00. I checked on her at 6:45 and she was dead. She was healthy, robust, active with no outward signs of illness. Her crop was fine, no discharge from anywhere and poo was normal. All systems seemed on go. I read a little on this site about "sudden death" but I still have questions. I want to make sure we did not do anything to cause her to die. We are going to scour the yard today for anything that might have caused this. What plants might poison a chicken? What toxins might be in our yard? Has anyone had any experience with this mystery being contagious? I don't want this to happen again. It is so hard when they die and she was one of my favorites. I feel so guilty because I feel as if I did not do enough for her. Please help.