today when i left my cochin hens out of their pen to free range, I noticed that one was missing I had 4 blues and 3 buffs. I checked in the chicken coupe thinking she was maybe laying an egg. Well I found her on the floor dead. These hens are about 3 years old. I have not noticed any of them being off feed. I am at a loss, but when I looked the others over this evening when they went to roost, I thought some of them had a little paler combs. Their poop is a dark almost black color with the white mixed in. I have never wormed them , is the black a sign of blood from parasites? Also they all tend to want to roost in the same 2 nesting boxes sometimes on top of each other would this be a possible problem. Your help would be appreciated. These gals are real pets and they follow me around the yard and meet me when i get out of the car. this really upsets me, I do notice that some have pooped on their feathers but they are so fluffy back there that it might be the reason for that . help please