Chronic respiratory disease?

[WildWyandott110]

A friend's 7-month old Welsumer hen seems to be exhibiting some, but not all of the symptoms of Chronic Respiratory Disease.
She seems lethargic, droopy, and her breathing sounds thicker than that of their healthy hens. One of her eyes is watering constantly, and both have semi-swollen rings around the eye area. She is not coughing or has any nasal discharge. None of the other 15 chickens are showing any symptoms. She eats and drinks, but rarely lays. She seems lighter than her sister, with a more pronounced breastbone. She apparently got it around the time she began to feather, and never shook it off since.
Neither I, nor my friend have had any experience with anything like this before. Please help.
Thanks.

 

[azygous]

Yep, likely CRD. You can't know which one without tests, but tetracycline or Tylan will both treat CRDs. Ask at your feed store for these, or go online to get them. Dosage instructions should come with the drug. Follow for the full course of treatment.