I am out of ideas...our now almost 15-month-old barred rock abruptly stopped laying almost two months ago. She was a prolific layer. She is bright-eyed, healthy-looking, etc. She is active, eating, drinking, seeks attention, etc. I checked her for mites (plus our coop is plastic which is hard for mites to live in, as I understand it) and had a fecal done (negative). I switched them to a soy-free layer, and maybe that didn't agree with her. I would switch her back to the original layer that I'd been feeding, but I have two 14-week-old pullets in the flock now. My understanding is that with a mixed flock, one should feed a pullet developer or whole flock feed + offer calcium, which I am doing. The new girls made their transition one week ago (switched food at the same time). Now our GL Wyandotte stopped laying :*( I don't know what to do!! All of my chickens are healthy, active, have plenty of coop space and limited free-range room. Our coop gets cleaned out daily. They have a dust bath with DE mixed in. Also, neither of the hens who've stopped laying have shown any signs of molting. Certainly the barred rock hasn't molted and she stopped laying 7-8 weeks ago. Any ideas??