I am new to chickens. One of my hens is very swollen, her abdomen is very hard and she can hardly walk without falling over. She is very hungry when offered food yet I can feel her breast bone when I hold her. She has progressively gotten worse over a couple weeks. I soaked her, checked her no egg that I could feel and now she's barely breathing smells terrible and I found maggots on her this morning!!! Anything I can do????