Altairsky
Songster
Layer feed + free ranging + oyster shell, I also believe it's highly improbable that the issue is on the diet. I witnessed my hens eat plenty of dead snail shells while free ranging so even if you don't see them eat the oyster shells, they know how and where to get their calcium.
It can be something going on like an infection. Respiratory infections often involve the reproductive system because what affects the respiratory mucous membrane can also affect the egg gland mucous membrane.
Sometimes chickens don't show any symptom other than glitches on the eggs. One of my hens had some sneezing one night, then she laid glitchy eggs for a week with no other symptoms, and normal but sterile eggs for another week (and it wasn't the roo's fault), then everything went back to normal and she even hatched some babies.
It can be something going on like an infection. Respiratory infections often involve the reproductive system because what affects the respiratory mucous membrane can also affect the egg gland mucous membrane.
Sometimes chickens don't show any symptom other than glitches on the eggs. One of my hens had some sneezing one night, then she laid glitchy eggs for a week with no other symptoms, and normal but sterile eggs for another week (and it wasn't the roo's fault), then everything went back to normal and she even hatched some babies.
