It was the weirdest thing. My chickens were where they weren't suppose to be, in my backyard. They keep escaping the fenced area for them that's just past my backyard. So, I went out there with food and had them follow me back to put them in the fenced area. My black chicken happily followed me back past the fence to chase after the food I was throwing. Then suddenly she's laying down, flopping around with her eyes closed. At first I thought she was just laying down, maybe dust bathing, because she was literally perfectly fine just two seconds ago. Then she just started flopping and died within seconds. I don't understand what could have happened. She seemed fine and happy seconds up until she died. Then out of no where just drops dead. I don't understand it. Does anyone known what could have possibly happened? Should I be worried about my other chickens? I just don't get what could have caused something like this?