Chicken open mouth breathing and soft abdomen below vent between legs

[RaesChicks]

I noticed my hen was open mouth breathing. I ran her down while she was free ranging and picked her up. She felt much heavier than my other hens. So I checked her for bugs and didn’t see anything as far as mites. She has a very poopy bum beneath her vent but you can only see it when you lift her tail feathers. Her vent looks clean and she’s grazing. But she seems softer than the other hens in the area between her legs. Should I be concerned?

 

[BackyardinWales]

My vet noticed my Cockerel open mouthed breathing and it concerned him, but he diagnosed my Toby with a neurological problem, and he was later euthanized because he couldn't stand. He only had a poppy butt from the antibiotics.