Hens are laying great, slowing down a bit, but we gather the eggs daily. No one has been on meds, all eating the same stuff (layer food & whatever they can get when they free range). Today I boiled some eggs. This was a large brown egg, no idea who or which breed chicken laid it. If I am not mistaken it is about 4-5 days old so we could peel them easily. So I get the eggs out, all is well when I come to this one brown shelled egg. As I begin to crack the egg I noticed the "white" isn't white. It is greenish brown. ALL of the "white" of the egg is solid greenish brown with one largish dark spot - which to me looked like on of the blood spots cooked (gross). There was no odor, the yolk seemed to be ok looking, but I was so freaked out I took it outside and tossed it in the yard. I should have taken pix of it, I know. The chickens came running over and scarfed it down. Of course I was kicking myself because, what if... what if it were "bad"? It smelled like a regular hard boiled egg, just totally discolored with the blood spot. At first I thought that the yolk might look like a little peeper, but it didn't, it was round and cooked - just encased in this terribly gross colored glob. Has anyone run across this before? What causes it? Can I prevent it? Any thoughts would be helpful.