Yoke color

[LuciferRoo]

My white leghorn just started laying (her 3rd egg was today).
What I noticed is that the yoke is much lighter in color than my other hens, all of whom lay brown eggs.
The yoke looks like something in a store bought egg. Not that rich, deep golden color I get from my other girls.
They all are pasture raised.
Is this normal or is she lacking nutrition?
Honestly, until 3 days ago I thought she was a young cockerel. She and two of her "roommates" are fed grower crumble. The other two are not laying".

 

[sourland]

Are the other laying hens being fed the grower crumble?

 

[LuciferRoo]

They get the same and also layer crumble.
All others are free ranging in the backyard. I have a mixture of more mature hens (maybe 18 months old), young ones that were hatched in early May and just started laying.
I was trying to give the older ones layer and young ones grow, but they don't seem to care about my efforts to keeps their feed in separate parts of the yard and nears their coops.

 

[sourland]

If they are getting the same feeds, I am not certain what is causing the lighter yolk color. Perhaps it will darken as she gets further into her laying cyle.