My boys fight similar to kids having fist fights after school. Hormonal and nothing like the cock fights long ago. Well some still exist in barns out of sight maybe. As for blood loss 20 drops don't mean a lot. Usually the Cornish are in their large hoop coop. 4 of them in a very spacious pad. They were out today pecking at some grass when their peace was disturbed and they took offense when challenged. Most of the Bresse roos have matured beyond the school boy hormonal fights now and have it out of their system and run free. They even roost on tops of coop in the open air now. If there is free ranging there will be some shaking other down over hens. I've got hens making more trouble at roosting time over who gets the top bar.