Poorly Chicken

Can anyone help with this one? I keep four chickens one of them has developed a fat belly and is walking about very slowly. She looks just like a penguin. She is eating and drinking ok and seems to be very alert but it takes her forever to get about. I have put cider vinegar in the water and also given them a tonic. The chickens are free-range and have a large area to roam

Crop issues or egg bound? I don't keep chickens (just ducks and geese) so I hope someone else will reply with insight. Sudden onset or gradual? Can you post a picture?

The chicken is very old and has not laid eggs for a long time. Will try and post a picture tomorrow

How fat a belly? Does it feel squishy like a water balloon, or is it hard?

There is a condition called "water belly" that could be the problem. It's actually a symptom rather than a cause, but finding the cause is complicated. It could be anything from liver trouble to internal laying, but the side effect is that fluid builds up in the abdominal cavity and can't get out.

If it is water belly, you can make her more comfortable by draining the fluid. Do a search online to see how that's done. When I did that for one of my hens, there was a LOT of fluid! Enough that I had to keep her isolated and change the bedding frequently, because she'd leak enough after every session to soak through it. You should know that whatever is causing the water belly is most likely fatal. Up to you if you want to keep treating the symptoms and keep her comfortable, or if it would be better to cull her so she doesn't suffer.

If it's not water belly, then there are several other things it might be, anything from obesity to a tumor.

I have one in that situation now. So big she waddles, but there's no fluid to drain, and she seems happy and alert in spite of the swelling. As long as she's content, I'll do what I can to keep her comfy.