I have a hen, an ameraucana/rhode island mix, around three years old, and I noticed the other day that she was walking kinda funny, all stiff and scrunched up, so I felt around and her abdomen is swollen. She doesn't lay anymore, so I don't think it's a lodged egg. Could it be that she's overweight? It's warm and not exactly soft, but not firm either, which makes me suspect it's fat. Right now, she's still active, but there's a definite waddle in her walk because of the extra mass. I'm not quite sure what to do about it. I don't want to take my other hens off their feed just because one's displaying weird behavior since one of them is still recovering her stolen weight from a near death encounter with worms. What should I do?