There are any number of poultry ailments that involve green droppings. All i am saying is that the color green in droppings can be the result of anything from laying pellets, to New Castle disease, to Aspergillusosis, a condition that may be the result of Aspergillus mold growing in damp or fermented food.
I asked my dad and he confirmed he had put green mouse poison out a couple weeks ago, also a cat ate one of those mice and got sick