Never seen anything like it! Poor baby!Thanks @ChicksnMore !
Here's a picture of the crushed eggshell that was under the roost this morning. The way it's broken, being totally crushed from all sides, makes me think that it collapsed inside the chicken, then was expelled.
If it dropped intact and broke when it hit the woodchips, even if chickens pecked on it, I don't think it would be crushed all the way around, but still all in one piece. That's my theory, anyway.
Hopefully all the shards of shell stuck to the membrane and passed out.
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