Once two of my chickens burned their combs on a heat lamp, and i bled, forming several small black scabs on their combs. I used Bag Balm, and applied it twice a day and it worked really fast. Your fingers smell like Bag Balm for a good hour afterwards, but it makes a huge difference for the chickens. If the bleeding continues, there must not be a scab forming, or the scab is being broken. Is there anything that your chicken may be continually getting hurt by? (A heat lamp, piece of chicken wire stickin out, or other hens pecking her?) If you find something, just remove your chicken from the situation until she heals. Hope this is helpful.
