I introduced 4 new chicks to a flock of 3 hens earlier this spring. Initially, the hens were slow to accept the new chicks and would not let them in the coop at night. Being in a colder environment, I would manually place them in the coop at night to keep them out of the cold at night. As the chicks became of age to start laying eggs, the dominant hen would let them in the coop to lay eggs. It became a hide and seek game and the newer hens would eventually get into the coop to lay eggs. But this is when the fighting started. Eventually, one of the older hens, found herself at the bottom of the pecking order (no pun intended). Initially, the older two hens would leave or alone and sometimes defend her. But now she has nearly no feathers left on her back near the base of her tail. Nearly the entire flock shows some signs of battle, but this one particular just can't seem to be left alone. She is constantly being chased around the pen during the day and she eventually just lays down and protects her head. But even the older hens peck at her back now and often cause bleeding which only increases the pecking at her. Really worried about this. One, what can I do about the fighting and two, what can be done to protect or change the behavior toward this one hen. I was thinking of putting some of that sour spray used to stop dogs from chewing on things? Should I put some of that on her back? I do have antiseptic wound cleaner and no more pecking lotion (which does not work at all. PLEASE tell me someone knows how to address this issue.