Yes, I see she's all fluffed up. That often means a chicken doesn't feel well. Right now, that's all we have to go on. We need clues.
Has Waffles just completed a tough molt? She hasn’t molted yet but some of the other hens have started molting.
Does Waffles seem to have lost considerable weight? If her breast bone has a knife edge to it, she probably has. She does seem to have lost weight, but she has access to food.
Have you felt Waffles' crop? Is it empty, full, soft and squishy, or lumpy and hard? You need to check it first thing in the morning to see if it's emptying overnight as it should. She could have a crop issue making her sick. Her crop felt normal but a bit smaller than the other hens’. I will check tomorrow morning to see if it’s empty.
Has she been scratching around in a compost area with rotting material? If so, is it deep and slimy underneath? The hens often scratch around on and around the horse manure pile, and in our horse pastures. They all scratch in the manure because there are bugs underneath, but it’s not slimy or anything.
Have you looked Waffles over well for signs of injury or signs of a respiratory infection? Runny eyes, dripping nares. Any sores on her feet? Look inside her mouth to be sure it's clean and pink and there are no crusty lesions. I checked her and she’s all fine exterior wise. Her comb did seem a bit discolored (a really light purple tint) and dry, so I put some bag balm on it.
Have you noticed her poop? Runny, watery, white, green, any red in it?
Her poop seems normal. This was the first day of symptoms and I felt that I should try and get on top of whatever is going on before it gets worse.
It would help you to answer the questions by copying the block above and then answering them one at a time right in the block. That way you won't miss any.