It's been a pretty wet lilting season...hmmmFeathers are mostly protein. I tend to see the sheath staying on longer when it is dry or when the birds are growing a lot of feathers quickly and they have a hard time keeping up with the preening which helps remove the sheath. When I raised more show birds, I would mist the birds or mist the liter in the pen to give the birds more moisture when it was really dry and they were growing a new crop of feathers.