For a couple of months I was plagued with gathering eggs bearing the obvious remnants of one or more eggs which had been eaten in the nesting box. Eventually I began to suspect this one hen; when I would come home after work to gather the eggs, I would first toss some goodies over the fence of their run. All of the girls would eagerly gobble them up, except that this one would see me head into the coop and come running, frantically scarfing up the feed as I scooped it into the feeder. I thought this was strange. Last weekend, I went out earlier than normal to gather eggs. There was a half-eaten egg in the nest. As I started to scoop in the feed, here came the suspect - caught her yolk-beaked! There is no excuse for calcium deficiency here; they are supplied with oyster shell at all times and fed expensive layer ration in addition to whatever else they get. I suspect that she had some metabolic disorder which caused the egg-eating behaviour. I am not a veterinarian, and she was at least 4 years old; suffice it to say that she is no longer a member of the flock. Someone told me that sometimes egg-eating will be taught by one bird to the rest. Fortunately this does not seem to have been the case, as I have had nothing but clean eggs since that incident. Just curious if anyone has any knowledge about this sort of thing?