One of my hens had laid an egg that is really odd. I've not in my years seen anything like it. All of our hens have the run of the yard during the day. There is lots of room in the coop and plenty of places to perch. I have read several articles about what might be the cause but none of the hens show any of the symptoms so I am totally at a loss. There is always good feed, lots of scratch, every day I toss out a chopped head of lettuce. There are no animals that chase any of the hens, unless you count the ol' silkie rooster. The only thing that might be upsetting her would be the thunder that we have this time of the year. She was here during the last rainy season so she should be used to that. It is what I would call normal in size. Any ideas?