Well if she isn't eating then it is probably time to quarentine and try some scramnble eggs, tuna, poly vi sol with no iron vitamins, oregano and garlic (immune system boost).
Good luck.
Wow my girls are on higher protein so that seems to be helping, there are a lot of feathets just not sure who it is that its coming from. Aw i hope you chickens feel better soon and can show off there proud plumage soon enough.