What would cause Olive colored raw yolks?

[EvansChicks]

Some of my hens are laying eggs with greenish/olive colored RAW yolks. They smell fine but just look sick. Ive been throwing them out but Id like to know the cause and if they are ok to eat.
I feed my hens laying pellets but they tend to get in the dog and cat food at times too. I let them free range for a few hours a day also.
Thanks for any help

 

[scratch'n'peck]

That is strange. I have heard that if chickens eat acorns they may have discolored yolks. Check out the link to this thread if you haven't already:

https://www.backyardchickens.com/t/446999/green-yolks-and-shredded-paper

 

[EvansChicks]

Thank you, that may be it their coop is shaded by a large Live Oak tree. I never thought they would eat them tho. The acorns seem like they would be too large but I guess not.
Im guessing they are to eat then??
Thanks again