One of our Rhode Island red hens has been acting sick. She will be fine one day and then she starts acting sick. Her comb on her head is fallen over and she does this thing where she acts like there is something in her throat she is trying to get out. We have looked and there is nothing stuck in her throat. She did this awhile back for a few days but then she was fine and got better. Now she is doing it again. She just stands there and don't want to eat or move around much. Has this happened to anyone else's chickens. I give her antibiotics in the water. Don't know what else to do.