Chicken trouble, feel you.
I've had a total of five chickens. Their demise went as follows:
Penny - I didn't secure the backyard gate all the way and the golden retriever got out. She chewed Penny's neck beyond repair and she died that evening.
Xantia - Unknown causes. I found her lying on her side but still acting fine. She never walked again, even after several days of care. My dad ended up shooting her.
Timia - Died in the heat wave of 2012. Close call with death when she ran away from home when Penny was killed. Later that day, I was looking out the window talking to a friend on the phone and saw our chicken strutting up the road and coming back down the driveway.
PJ - Died the same day as Timia for same reason. Had a close call with death when a neighbor dog attacked her. She took refuge under the chicken coop and only lost some tail feathers.
Lacey - A neighbor dog got inside the coop and ate her. I went out and shot the dog repeatedly with my airsoft gun. When it yelped, I saw the neighbor coming down the driveway and went quietly into the house to let her discover the scene on her own.