We have 9 chickens one is a rooster, all of them are about 5 months old and on the verge of laying an egg...about a month ago I noticed this (see pictures) under their roost in the morning. I have called multiple vets to see if someone could test a sample for parasites or disease with no luck. I figured out which one is having these and I have closely monitored her and she is healthy, eating, drinking and gaining weight. My local feed store gave me some herbal remedies to put in the water and also suggested yogurt. Which I did do. I already add apple cider vinegar to their water. I stopped noticing blood and thought things were getting better until I spotted more yesterday morning. What should I do?