ok I don't know what happened but I know I lost a little polish chick. I can find nothing visibly wrong with it. It was active, eating, drinking, playing as of midnight. 8 hours later it is gasping and jerking its head backwards in my hand and died. My teenage silkie chick was in with them. I had to serparate him from his nests mates because the roo chicks were being too pushy. seemed like a reasonable thing to do. All of these are still in confinement. I bought them all at the same place just a few weeks apart. No one else is showing any signs of this. no pasty butts, that I can tell no crop issues, no drainage, no sneezing, The only thing different from the other chicks I have raised is these all seem to sleep all sprawled out instead of clustering. And its not too hot. they do this under the light. there are parts to get away from the head. fresh water and tons of food avail. Any clue what happened. Any clue how I can prevent it.