I have 27 layers and one rooster which are 2 years old in one pen. In a second pen I had 20 younger birds 16 weeks. 6 roosters and 14 hens. Pens are side by side 6 weeks ago I found a young hen in with the older birds and its head and neck skin was missing from the comb to the base of the neck. It was still alive and I thought that maybe it would survive. Seemed to be eating and drinking. It new home would be with the turkeys as they didn't pick at her. Next day I put her down she could no longer see as the fluid was in her eyes. Thought this was a one time case. Couple more weeks pass the wife finds a young hen in the other coop with her head buried in the saw dust jammed in the corner. Her skin too is also missing but not as close to the eyes. We moved her in with the turkeys and is doing very well still. Her skin and feathers are starting to grow back as a matter of fact the scab just fell off. It was 1" X 3" long. I few days after the last attach I found a dead young hen on the other coop It was missing the skin from the neck and was picked right to the bone. Then we get 3 very nice looking very colorful bantee roosters and because of their size we put them in with the young hens. They are still half the size of the hens. Bantees can fly out all the time and first day they all got into the old birds coop. For their size they held their own against the hens. The rooster was a giant to them but they did not stand down. So yesterday I find a bantee rooster all beat up. Covered in mud and is missing his comb. Pecked down to the skull. Not sure who did it but a second bantee was also mud covered. So maybe they fought but I tend to think it was the old bags that have been attacking and killing the birds. Any ideas as to what I can do???