Stumbling, ataxic pullet - need advice

[houlahoula]

Found my 6 week old EE pullet laying on her side today. At first, I thought she was dust bathing. I lifted the door on the tractor and she stumbled around like she was disoriented, weak, and ataxic. She kept falling over. These symptoms were of sudden onset and all of the other birds are behaving as usual. She is in a mixed group of 8 birds that she has been raised with. Any suggestions as to what may be the cause? I have isolated her and she is eating and drinking well. She is having normal stools, formed and not discolored. No blood observed. She is well-bodied and seemingly healthy otherwise. Please help! I want to keep my flock safe and healthy.

Thanks for any advice.

 

[sevenchickens]

Is she from a hatchery? or did you hatch her?

 

[houlahoula]

purchased at a feed store, she came from "ideal". called to find out marek's vaccine status. will not know until tomorrow