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Is she laying eggs, what are they like?
Feel her abdomen for bloat or fluid. A crop that is squishy and not emptying overnight, I would begin treating that (see the article link below). The poop looks like it may have egg yolk in it as well(?)
What dose of Corid are you using? I would finish the course of Corid it shouldn't hurt anything. She may be having some reproductive issues which can be common in laying hens. These conditions can also cause some crop problems.
If possible, get a fecal float to rule out worms as an underlying condition as well.
https://www.backyardchickens.com/ar...w-to-know-which-one-youre-dealing-with.73607/