i have been caring for our sick chicken since Christmas Eve. She seem lethargic and doesn't want to eat or drink. I have used a syringe to get water in her, I have some antibiotics but not sure how much to give a single chicken. Her bottom ( vent area ) has been poopy and she appears to have diarrhea. I have been giving her a bath to keep bottom clean. She normally eats meal and pellets. I have given her probiotics what else can I do? She's in the house in a kennel away from the other chickens who seem fine.