I have seen this before, from my hen Buttercup. It was not really a lash egg because there was no infection. It was almost like a giant meat spot

I took Buttercup to the vet immediately afterward (along with the creepy egg), but they did not find anything wrong with her. Prior to the creepy egg, Buttercup’s eggs had an increasing number of meat spots as well as shell quality issues (wrinkles, body-checking, thin shells). Then she took a short hiatus before laying creepy egg.
After the creepy egg she did eventually resume laying normally. Everything was fine for approximateky 8 more months. Then the same egg quality issues began (meat spots, shell issues). Frequency of laying declined. She also Laid a fairy egg for the first time. Last week Buttercup passed away after a rapid decline in health. She had just turned 2.
I know this probably isn’t what you wanted to hear but I still hope it helps to hear some one else’s experience. I would say don’t panic. But do keep a close eye on your hens. Watch their behavior, poop, and appetite. Make sure they gets adequate calcium from either oyster shell or layer feed. If at all possible, try to figure out who laid that egg. Then basically just take good care of her.


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