Missing tail feathers on chicks

[Bokbok]

One of my Buff Orpingtons has no tail feathers, while every other chick has plenty. I don't remember if she had them before and now they are gone or what, I just noticed the difference when I was in there a minute ago. The chicks are two weeks old today. Where her tail feathers should be is just this raw looking patch with stubble sticking out.

 

[TheBigWRanch]

The other chicks may be picking at them.

 

[CarriBrown]

They may be picking because of stress or any other number of things. Use a heat lamp that gives off a red light and they will stop picking.