To this...
Don't be alarmed, it happens every year, some times more or less then previous years. I still tell my girls they are beautiful, in spite of them looking ...well... not their best.What am I talking about?
Molting. If you don't know what it is, it can be scary, because they really do look sick and they may stop laying. Don't worry, in a couple to few weeks it will be over and they'll be back to their beautiful self...and back to laying eggs.
Not sure about the whole molting process?
Here is short YouTube video from Nutrena (click Nutrena)explaining it.