One of my 3 year old hens is walking like a duck, legs apart like she's got something between them. She is also breathing hard with her beak open. She also has a hard time jumping up on anything. She still acts normal otherwise - eats, drinks, scavenges. She's been like this for a month or so. I have five chickens and this is the only one acting like this. I had her in my lap recently and her belly feels hard. I don't know if she's pooping because she hasn't pooped when I'm watching. I think she is because she has some dried on her tail below the vent. I did check the vent to see that it wasn't blocked. The feed has not changed. They all get the same thing. I gave her some yogurt which I use for sour crop. She ate some, but nothing changed. I don't think she is still laying, probably since last summer. Even if she was egg bound, wouldn't she either have passed it or died by now? Any suggestions? Thanks.