About 2 months ago, we acquired 2 Leghorn hens. They were about 6 months old when we got them. After a couple of days, one hen's but was picked clean of the downy feathers around and below her vent, but there were no feathers laying around anywhere. I put blue-kote on her and everything seemed to be ok. When the blue=kote started to wear off, the other hen would not leave her alone. The pecked one wound up with an infection and died. My wife noticed yesterday, the Leghorn hen trying to pull feathers out of guinea's neck and ate what she pulled out. We have been trying to get the guinea to roost with the chickens -- that's why we got the chickens for in the first place -- to keep the guinea from roosting in a tree in very cold & rainy weather. Any ideas why this one Leghorn is pulling & eating feathers? Our coop is 4 x 8 feet, well lighted, and kept clean.