I don't know if this is silly or not? I recently bought 3 ISA brown hens that were already laying, and moved them into the coop. I placed a dummy egg in the nesting box to show them where to lay. They were laying since day one, each one of them laying in the nesting boxes. I decided to remove the dummy egg after 2 weeks as it was getting dirty, and it kept fooling me every day!! The girls all laid for one more day, and all of a sudden, they stopped, all three of them! I haven't had an egg from them in a week. They haven't hidden any eggs anywhere, and there are no nests in their big run. I just can't figure it out??? No sign of lice or mites either. Could it be that because I removed the dummy egg, that it's triggered something that has stopped them laying? It's the only thing that I changed!