Once a year I rotate Zimecterin horse wormer into my deworming schedule. I recall my vet telling me not to let my dog eat manure afterwards because it would make him sick. (Why MANURE doesn't make him sick to begin with??? IDK) I didn't have chickens then. Now I do It's that time again for the Zimecterin and I'm afraid to give it because my chickens totally break up the manure piles in the barn stalls. My barn isn't finished and right now I can't keep them out of the stalls. Is there a danger to them eating manure after worming?