My dark brahma cockerel has been pulling out an eating neck feathers! He is aggressive about it pinning their heads to the ground before he rips some out and eats the baby feathers!! I have tried everything, apple cider vinegar in the water (possible mineral deficiency) upped protein (black oiled sun flower seeds/ still on 16% starter grower/ left over scrambed eggs and meat scraps) i have read this behavior might be common for those who claim a pullet in attempt to reproduce with them( biting their neck so they can jumpnon them to mate) he has done this to the two other roosters he lives with and there is no consistant pullets that he claims. He is free for the taking and have no possible interests. At what point should i throw in the towel and just cull him!? (He is not human agressive only toward other chickens and cant free range due to predators) ..