9-yr-old's abdomen feels like a water balloon

[frankenchick]

Bianca is a 9-yr-old NHR. She has to be watched carefully for fly-strike, but otherwise is pretty healthy and a good layer. Lately, she has been walking very upright (my DH calls it goose-stepping) and her abdomen feels like a water balloon. Is this ascites? It's the closest thing I can find, but I'd like to be a little more sure.

 

[Eggcessive]

Egg yolk peritonitis, internal laying, and ascites can all be causes for upright walking, penguin walk, or lameness. Ascites or fluid in the belly, can make the lower abdomen feel tight and full of water. Ascites can be a sign of heart failure, and egg yolk peritonitis. Fluid can be removed a little at a time to help relieve pressure.