One of my RIR's is laying an egg about one every other day. She seems healthy with a good appetite...but I've noticed her eggs look a bit odd. They come out with what looks like splatters of mud or plaster on them. Thespots are a beige color and are hard and come off of the egg if you pick it off w/your finger nail. She is laying in a clean nesting box. I cracked open one and the only thing different is there seemed to be a blood spot? floating in the white. Any ideas on what is causing this? Are the eggs still safe to eat?