Hey guys looking for help. Introduced a rooster about 3 weeks ago to an existing flock of ten hens.. After a 3 day "breaking in" period, everything seemed to be going smoothly. This afternoon I noticed 1 hen that looks like she has been in a war. Her back is bare and her comb is bleeding. She hides in a nesting box in the coop, but when she comes out the rooster immediately rides her again.....and stays on her. Each time she looses more feathers and I noticed other hens gather around to eat the pulled out feathers. Should I cull her, the rooster or what......They are being feed 16% protein with boss, scratch grains and a little alfalfa every 3 or 4 days. Any help would be appreciated.