how long is a chicken brooding?

[gigelus2k13]

I guess that this question has been asked a million times already, but here it is.

One of my Buff Orps has been warming two golf balls for 5 weeks now. Poor thing is a shadow of what she was, she feels very light and her feathers somehow don't sit right on her. I recently started taking her out of the nest every morning when I clean their house and she eats a little scratch then rushes back to the nest.

I am concerned for her well being, is she hurting herself on this hunger strike? How long is the worst case (which it seems I'm about to reach)?

Originally, I separated her in a small fenced area without bedding, but after an incident involving a hawk (which got tangled in the fence while the hen flew by his beak), I decided to let her be. However, 5 weeks later and the way she looks make me think that she cannot hold on much longer...

Cheers,

 

[Animol]

In your shoes I would take away the golf balls, if she continues to try and sit on them then take away the nest (if you can) or section it off somehow. She'll probably make a fuss about it but she'll survive. If she still doesn't stop you can always change her location. She sounds like a very dedicated wants-to-be-mother so you may need to remove her forcibly from making any attempts at brooding in the future - or get some fertile eggs if you don't mind the additions to the family. Have food and water available for her to eat drink at all times if you don't take her off the nest so she can reach it without getting off the nest.
Some chickens are remarkably determined to hatch their eggs - as proven by my sebright yesterday when she got off the nest for a snack - came back and found someone else there and sat on the hen twice her size pecking her until she went away.