Disease or just brooding? Yellow skin, refusing to eat...

[dianastar]

I have a golden-laced cochin about 1 1/2 years old. About two weeks ago one of my hens wouldn't leave her nest box and we have no rooster. I thought she was brooding and she would leave after I collected the eggs, like my other hens do but she still sits in the coop not eating or drinking and today i noticed her usually gray skin had patch of featherless yellow skin on her back. What's going on with my chicken?

 

[debilorrah]

She is right at the age to go through a full molt. Any minute now you will find a boatload of feathers in your coop.