We acquired 4 older white leghorn hens from a neighbor in May. It's been a warm humid summer. And we still only get about 3 or 4 eggs a week from the whole flock. And it looks like there is egg yolk smeared on the outside of the egg, so we have to really scrub the eggs when we collect them. It's yellow and smeared all over the egg, and the grass in the nest sticks to it. It's like a broken yolk that gets dried onto a plate. What is this really? I considered that it could really be broken eggs (cannibalized), but there is no evidence of broken eggs or pieces of egg shell in the nest. What can I do to fix the problem?