https://www.backyardchickens.com/articles/who-is-laying-and-who-is-not-butt-check.73309/One other thing, have you checked pelvic spacing?
So you locked them up last summer?
Where in this world are you located?
Climate, and time of year, is almost always a factor.
Please add your general geographical location to your profile.
It's easy to do, and then it's always there!
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