My blue andalusian is pecking my brahma- adult beak trimming?

[goldengirlmum]

Update: I have been feeding the chickens wet cat food, dry cat food, oats, and any scarps I have. Still a red butt.... I haven't tried the blue spray? I dont even know what that is. I bought peck protection lotion that was purple-ish. But it had tea tree in it and then I read that tea tree is bad for chickens.