This is front and back view of 'pillow' shaped egg one of my Barred Holland or Partridge Plymouth Rock hens layed recently. Shell feels heavy and thick.
My 5 gals share a nest box and I've had no repeats but jus curious if anyone knows what this shape may be about?
Something weird happened in the shell gland while the chicken was laying the egg. Usually I get odd shaped eggs similar to this when my girls are under stress, they had something scary happen while the egg was in the shell-application portion of their egg making system. Older hens can also be more prone to lay these. But it could just be a one-off. No need to worry. Also, I don't think there's a way to fix it if they make a habit of it, if it's too weird I feed the egg back to the chickens.