Yes the egg shells had weird bubbles on the shells.
Don't give your chickens egg layer feed. Give them non medicated hatch to hen feed, meat bird finisher or something like that. Look at the tag on the nutritional information on the feed bag and make sure the calcium content is around .5...
I was giving my hens a 18% protein egg layer feed with free choice oyster shells on the side in a dish. I was getting a lot of bubbles on my eggs and I read that the added calcium in egg layer feed 3.5-4.5% can cause egg bubbles. The added calcium in the egg layer feed also caused kidney failure...