We're raising our first batch of chicks. Half are Red Bros and half are Cornish Cross. Some of them have what looks like very poopy butts. The poop is caked on and a few had it pretty bad. Those few also lost their fur around the whole picky area. One in particular we had to cull because he was in such bad shape. He lost all of his fur on his underside and legs and the area around the anus turned white and crusty and he was losing water. Still seeing some with poop caked on. I make sure that the vent is clear but I was just wondering what this is and what causes it. Any feedback? I'm new at all of this and I'm so grateful for this message board. Thanks!