I have a hen that was born late May of this year ... so that puts her 3 months and some change. I just lost a Polish to something. She (the polish) became real lethargic, and her breathing became real slow and heavy. Her course ran about 1 1/2 weeks. She kept getting worse and worse, so we put her down. I'm starting to see the same thing in my Wyandotte. I know everyone says this, but this hen is my baby ... she's the sweetest out of the five I now own. Here's the facts I know: her poop looks regular; greenish with the little white stuff on top .. my wife actually saw her poop yesterday. For the past two days she hasn't ate the chick feed that the others do, but she ate some Greek yogurt with vitamin E in it about five hours ago. She mostly keeps her eyes shut now, and can't stand up on her right side. She will attempt to stand up but will fall right over to her right every time. Her leg nor wing are broken, and I don't see any bite marks. All my hens supposedly were treated for Mareks before I got them as babies. I gave her a real close exam, and didn't see any mites, or bugs, and her vent looked okay. Her crop isn't full or hard. She actually hasn't ate much today or yesterday beside the little bit of yogurt. She does NOT have any running discharge around her nose or mouth or eyes. We use wood shavings (not cedar) .. pine "I believe". I have full faith that the bedding material is okay. She acts like she's super sleepy. I started noticing her change two days ago. She didn't even fly up to the perch for the past two nights. The other chickens pooped on her, so I know she didn't move all night. If you pick her up, her eyes will open but almost instantly close. That's about all I can tell without cutting her open, which is what I'm trying to avoid. I can't tell you much about the polish I just lost, other than I thought she had wrye neck. Her neck/head would instantly fold under her chest, and she eventually became non responsive. We put her down about three days ago after about a week of attempted health care. I'm hoping there is nothing contagious in my coop. I don't see anything similar between the way these two birds acted other than they both are / were sick. A few facts about the coop area ... All poop in the coop looks okay/normal. None of the hens are laying eggs yet. I have four other chickens, but they're all about the same age. I just bought a new waterer from Southern States, but I cleaned it pretty good, and keep fresh water in it. The coop area looks like a normal coop ... some of the boards are treated wood, but none appear to be pecked at. We keep if fairly clean, so it doesn't have an overly strong odor. I noticed an average sized rat nearby the other day and it's breaking into my shop where the food is located. My chicken coop/run is built onto the side of my shop so I imagine he's probably eating from the chicken food in my feeder as well as the bags inside the shop. I haven't seen any rat turds inside of my run "yet". I'm feeding all my chickens Chick Starter feed. I do not have any oyster shell inside their area yet for them to eat on. They seem to be munching on the small grains of dirt that are loose in the run. I'd rather loose all of my other chickens than this one, but nature has it's own way. If she has to go, then she has to go ... but I don't want her to suffer for the next week or two before I say "okay, she's had enough". Let me know if there is any other information I can provide. I could even possible upload a video to youtube if it would help. Any ideas?