She has what is called stridor, and it could be that she has something in her airway, but also could be a respiratory illness. You can look inside the throat with a flashlight or head lamp for any yellow or grayish patches, or something blocking there. Check her crop for impaction. The feather issue looks little like lice eggs, but it isn't that plain to see. Feather picking aside from lice or mites can cause this. Here is a good link with pictures of lice eggs and treatment suggestions: http://www.the-chicken-chick.com/2012/08/poultry-lice-and-mites-identification.html