Two or three of my hens (A little more then 2 years old) aren't acting quite right, one in particular. They aren't quite as active, and look slightly poofy, like they are cold or something. (70+ degrees the past couple days, though nights have been 40s.) The on in particular has white poop stuck to her butt feathers and her crop feels slightly squishy, though small, and at first I thought it was sour crop. But she eats drinks and poops, and still runs away and when I go to catch her. I did lose one bird from what I think was sour crop, and she was absolutely not moving or eating and died within 24 hours. I've noticed the difference in behavior for a couple days now with the others so I'm not sure what it is. Any thoughts?