Condition or illness that would cause a chick to not make feathers?

[wondertwinpower]

Is there a condition/illness that would cause a chick to not make feathers, and at what age should I become worried if she still does not have any feathers? I received her in my 15 Brown Egg Layer assortment (+1 meal maker) from Meyer Hatchery. I received 4 black chicks. Someone suggested this one might be a Jersey Giant since she is feathering in so much slower than the rest (really all of the other 15 are mostly feathered, with a few that have a little bit of fuzz left, but nothing like this). I have a buff laced brahma and a gold laced brahma that I hatched 2 weeks ago that have more feathers than this black chick.
edited to show the photo instead of a link

 

[jdoane]

Have you checked with Meyer. They were actually pretty helpful when I had a question about how fast one of my chicks was getting feathers. I actually just got on their webpage and did the live chat thing.

 

[wondertwinpower]

Here's another picture, next to one of the chicks who hatched at the same time and arrived in the same shipment.