I ordered some chicks from ideal poultry and picked them up a week ago. The first 4 days a few of them had pasty butt so I was washing chicken butt several times a day. That has seemed to stop and every one seemed to be doing fine. I checked on them for the last time before bed last night and everyone was happy, eating drinking and running around the brooder. Being normal little chicks. I woke up this morning and on of my Roos is dead. No sysptoms of illness or stress the night before. So when I woke up it was a lil shocking to find him dead. I ordered 3 Roos and 12 pullets and they also sent me 8 Roos of a different breed for warmth. Everyone else seems fine this morning other than the one who died last night. What could be the cause?