I've been reading about this and seems to me that bloody poop is the most prevalent symptom. My girls have been laying since late Dec. Although I have not seen this trait, I am wondering if I should do a preventive dose. I have seen some dark black watery poop but don't know which one is responsible. All RIR's ...can't tell them apart! Also, they have never been wormed and should I do this too and what is the best one to use. Would hate to throw l4 days of eggs away since I'm just now getting presents.