Hi all. I'm afraid I might have a sick chicken on my hands. Your opinions are greatly appreciated! Bird: 9 mo Black Cuckoo Marans, approx. 7 lbs (Dolly) Symptoms: Went from laying 6 eggs/wk to laying only 2 paper-thin, nearly shell-less eggs over the last 5 days. Today she's got lots of runny white and brown diarrhea and poo-pasty bottom fluff. Her poo is really sick/sour smelling. Other than these two issues, she looks healthy and active, no signs of trauma, and is eating and drinking OK. The rest of the flock is symptom-free. Flock conditions: We're in Boise, ID and we only keep three chickens. The girls free range in the yard all day when the weather is good, though they are kept in a covered outdoor run when the weather is poor. Their inside coop is equipped with timed christmas lights for 10 hrs/day, with super-dry with soft pine shavings for bedding in the entire coop floor and nest boxes. Everybody eats non-medicated layer mash, oysters and fresh water daily, all kept inside the coop. We worm with DE for 4 days every month or so. Treatment: I brought her in the house for a warm bath to clean and trim the pasted fluff. Now she's isolated in the mud room just off our kitchen with a space heater blowing to dry her off more quickly. She has a yogurt and mash mixture and has eaten a bit. I medicated her water with antibiotics (200 mg tetracycline hydrochloride) and electrolytes. I medicated the other girls' waterer in the coop as a precaution. I'm worried that it's worms, or worse. I'm planning to keep her inside for observation until she begins to poo regularly and lays a healthy egg. Is there anything I'm doing really wrong? Any additional steps/advice? There are some photos below, taken minutes ago, for reference. Do the stools look wormy to you guys? Any advice you've got is super appreciated!