I'll start from the beginning..... A few days ago some of my hens got into the barn where they should not be. In their area I've cleaned everything up and covered old paint etc.. But in the rest of the barn (it is a very old barn) there is definately things they should not be eating. So the weather was cold and they got into the "restricted area" I found one up on the old work bench roosted and pecking at all this white stuff. I'm thinking it was old calcium chloride. So, of course, I took her down and shooed everyone out. We secured the entrance so they could not come in while free ranging again. Then the two days later one hen's comb was very gray. She was acting normal, walking around, scratching, eating and drinking. I figured this is the one who ate the calcium chloride. After two days of watching her and the rest her comb started to get more red again. Egg production had been normal during this time. The girls are young - this is their first winter and some are in moult. I think they are all laying but not sure. I have 13 hens and get 6-10 eggs a day. Then yesterday I got an egg that had a very thin membrane/shell. It was laid late in the day. And this morning when I went out under their roost with the poop pile was a yolk that was in a thin membrane only. It must have been laid/pooped out during the night or dark of the early morning because it was undisturbed. So finally the question - do you think one of the birds is sick? Or is it just the calcium chloride working through the system? I don't know who lays which eggs I just collect them through the day while I visit the girls. They have free choice oyster shells available and laying pellets, also plenty of water. Thanks for the input!