Sickly Chicken Questions and Help?

[Burlinghams]

We got this batch of chickens in october
We have lost a few and they all looked like the chicken below. They have been living in a well insulated shed protecting them from the cold i have checked the for mites because of the lost feathers and have done all the treatment and haven't seen mites
But a few symptoms is they are lethargic, loss of feathers, no balance, usually die within 3 days of looking like this,
We bring them inside away from the others
We have sanitized and cleaned and scrubbed down the shed after one dies but it seems like we are having a terrible time with this batch of chickens
They are 4 months old and this size
Golden Laced Wyandotte

 

[ChickenWhisperer101]

COCCIDIOSIS!!!!!
Symptoms are lose of balance, very lethargic and paralysis or death.
Try medicated feed and the pics below. They’re life saving!!!

for the nutri-drench put it in her water and it’s good for all chickens in general to keep them healthy.
Do they have the option to run around outside? You should let them once their better. It keeps them happy. I really hope this helps.