lethargic chicken

[karus75]

I have a sick chicken. She is 4 years old and first started walking slowly, still does, about a week ago. She doesn't have a full craw thing but does eat a little and is drinking. She is also pooping. I can see her breathing but not as if she is in deep labour. She also doesn't jump up on the roosts any longer. We have had 4 chickens pass away w similar symptoms in the last 4 years. Not one right after the other but probably the last one died this past winter.

 

[Sunflower]

Are her feathers ruffled? Does she hang out by herself? Have you checked for mites or other types of bugs?