PLEASE READ AND SEE IF OYU HAVE ANY FIRST HAND KNOWLEDGE OF THIS. OK so a week or two ago, I noticed that one of my 25 hens didn't "seem right" so when I picked her up I noticed that the front of her chest, above the breast bone (the part that is just below the neck, but, not between the legs yet) was large and "squishy". Felt like a ton of fluid deep under the skin filling the whole front chest area, but, not going up into the neck. She is now seemingly "normal", but still has this giant squishy sac filling the front area if you touch it. I checked a few other birds, everyone was fine. All are acting normally. Now, two weeks later, I just saw my favorite hen (of course) standing funny with what appeared to be her butt feathers puffing way out and towards the ground. I picked her up and she had a bunch of poo stuck all down her butt....brown and white....While I was taking care of that, I all of a sudden realized that her chest too was "full of fluid" feeling. As I had her sort of inclined looking at her bum, my son watched a bunch of liquid run out of her mouth (like throwing up) and she kept swallowing after that funny. I put her down and she gets around just fine, but, is puffed out funny. What is going on? Thank you for your time.