I had a rooster die recently of "dont know what". He was fine the day before and in just a few hours, lethargic, barely breathing, and a white pasty stuff hard as concrete caked to his vent feathers. Dead in a few hours. That was the only occurance. He was in a chicken tractor with 2 hens that displayed no signs or similuar symptoms. To date - these 2 hens have not developed anything. In a different chicken tractor - on the other side of the property - 2 young Pullets about 8 months old, one a RIR, the other a Black Astrolop - developed a white pasty stuff on vent feathers - not to the same degree as the dead rooster though. I pulled them out of that tractor and quarantened them. I put them on tetracyclene in their water and they seem to be doing better - well, they are still alive. White pasty stuff on their vent feathers are lessening if not gone. Any idea of what the pasty white stuff is?