All my laying hens get layer pellets and crumbles, oyster shell and have a sandbox for bathing and eating little pebbles. I've done some reading and have found some to say that it may be a calcium deficiency. But, I find that hard to believe with them getting plenty of oyster shells. Does anyone have any idea why I would be getting a wrinkled egg. It seems like it is just the one hen. It doesn't really bother me, I just wanted to make sure that it wasn't something wrong with the hen that I could help fix. Thanks for any advice?