We are so new to chickens and don't have any idea what is going on. We haven't seen any evidence of mites or lice. Three of our Rhode Island Reds have died in two days now. There is blood in the coop, but no sign of blood on the chickens. I even looked in the mouth and vent of one. No blood. We have seen some blood in some stools, but not enough to account for the blood in the coop. Any ideas of where to start looking/researching? We have cleaned out the coop today and used a weak bleach solution to disinfect and rinsed with vinegar.