3 yr old hen -- she had dried packed poo on her hind end. I clipped and worked till she can probably poo again. She's doesn't have anything respiratory going on. But she just stands around. The other birds have picked up that she is not feeling good and pick at her. I've not had any sick birds in the 5 yrs I've had chickens. What could this be?? Should I separate her and give her some ProBios in her water and maybe some yogurt? If she had diarrhea all that stuff on her butt wouldn't have been dry and caked. This has probably been going on for 2 days. Any ideas?? Appreciate your help!!