*HELP* VERY Sick Chicken!!!

[sacramento]

Hi I have an americana chicken, about 7 months old, and she has multiple very concerning symptoms. they are:
- vomiting
- droopiness in the head and wings
- head and neck feathers are turning white
- skin is flaking
- out cast from the rest of flock
I have caught some of the other chickens pulling her feathers on her neck and head, and in general pecking at her. Blood has been drawn on her comb from the pecking, so I put her in the 'Isolation Coop' as I call it. She has a heat lamp, which she appreciates, and everything she needs. the coop has a little run on it for her and everything, but in the mean time, i don't know what to do! Help!

 

[Eggcessive]

I think I would do some research on Mareks disease. The vomiting sometimes signals sour crop which can also be part of Mareks along with the flaking and weird feather problem. Click here for some reading:
http://www.the-chicken-chick.com/2012/04/answers-from-chicken-vet-on-impacted.html
http://extension.unh.edu/resources/files/Resource000791_Rep813.pdf
http://partnersah.vet.cornell.edu/avian-atlas/search/disease/502
http://www.examiner.com/article/how...mareks-disease-michigans-small-chicken-flocks

 

[sacramento]

She was vaccinated for it. Does that matter at all? Or could she still have it?

 

[Eggcessive]

If she was vaccinated, I would think not, although a very small percentage can still get it if they have poor immunity or the vaccine was too weak. Check her feather shafts for sings of feathermite eggs. You might want to place her in a cage inside the coop and run so that she doesn't lose her place in the pecking order--even though she seems to be on the bottom. Click here for pictures of http://ohioline.osu.edu/vme-fact/0018.html: