Are you talking about the white underfluff on the feathers?Lima damaged her throat when she was at the battery. I mentioned how the feathers were growing back white from her breast to and up her throat.
I'm pretty sure that's normal, and not caused by any kind of damage.
Once she regrows feathers on the bare spot, the white underfluff will not be visible.
If you grab a different sexlink, and part the throat feathers to look at the underfluff, you should find the same white there.