Truth be told, I've been chicken about letting my hens free range. Thus, they had never been outside their run (which is an adequate size). Yesterday was a gorgeous day, and I just decided to let them out. The four of them had a great time, eating grass and foraging under the leaf pile for bugs. They will be 3 years in April and I felt really good about finally getting over my concerns. Today, I let them out and everything started out just like yesterday. Then a couple of them went back into the run and stayed there. And one of them is just standing there, eyes half closed, tail tucked (she looked and acted fine this morning). Not a good sign, I know. I picked her up, looked and felt all over and there is nothing obviously wrong. I don't use fertilizers or pesticides, so there's not a chance of that sort of poisoning. They have clean water, food and grit available as needed. It seems almost too much of a coincidence that yesterday was their first day out and today she's seems ill. The other three are fine. One has stayed in the run with the one that might be ill. The other two are out having a fine time. Any ideas?