This is the worst case you may ever see--she gave Baytril: https://www.backyardchickens.com/t/818895/wet-and-dry-fowl-pox-xxx-rated-graphic-pictures-of-pus-and-scabs
I would save the Baytril for if they become ill--an eye or skin infection, or the wet pox in the throat and nose. You may want to apply some iodine to the scabs to dry them up--when they are wet they can spread more I believe.
This looks to be avian or fowl pox. It is a virus, so antibiotics are not useful. This is the dry fowl pox, and their is a wet version that can affect the airway. Look inside the beak and throat for yellow cheesy patches if any of your chickens are having respiratory or breathing difficulty...