She could be in renal failure. Are you feeding high proteins?
No always stayed away from high proteins. I only give a little extra around this time of year when everyone is molting.. Their 1/2 acre of foraging area is a little desolate right now but when I get home from work I let them roam the 10 acres where there is lots of goodies. They are in that area for about an hour until it gets dark. That's why I feed them their FF in the morning when they get out of the coop.