Hello, we have one of our favorite hens in trouble. She is a 5+ y/o Barred Rock. She started limping a few months ago. I know that seems long ago but we were hopeful she would recover. We just made life easier but didn't treat her leg and it didn't look broken. We suspected old age... Her leg never swelled. Her leg got SKINNY. Now it is lame and seems useless. What is WORSE is that she is pecking a large hole in her own back! It is a half dollar size and getting deep! We have her on antibiotics and electrolytes. But she is eating and drinking well. She can get around some. What on EARTH can be causing this? Thanks for any help.