Buff orpington tail feather color

[Kaesi2020]

Hi everyone! Of my flock of six 13 week old pullets, I have two buff orpingtons. I notice that their tail feathers are changing color a bit, they now have brownish/blackish marks on them. Is this typical of the breed? I tried taking a close up picture below.

 

[swamphiker]

My buff orpington has darker feathers like this in her tail as well. I think it is common, especially for hatchery birds that are bred for production rather than conforming with breed standards.

 

[MysteryChicken]

A couple of mine have this, but the other two I have don't.

My Orpingtons are larger, & better quality then my last ones.