Brown yolk

[Lizardsped]

What could cause a fresh chicken egg from a white leghorn to have a olive brown yolk? The hen is 18 months old.

 

[Duck_life]

Pictures?

 

[Uff Da]

I've heard of chickens eating something that turns yolks greenish, but I don't remember what it was.

 

[aart]

What could cause a fresh chicken egg from a white leghorn to have a olive brown yolk? The hen is 18 months old.

Pics or egg yolk would help immensely.
Did this just start...or?

Oh, and... Welcome to BYC! @Lizardsped
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