Why is my Pekin turning yellow?

[Miss Lydia]

@onaharley had hers turning yellow. Vet said the cause just can't remember what it was but I think feeding corn can cause it too.

 

[casportpony]

@onaharley had hers turning yellow. Vet said the cause just can't remember what it was but I think feeding corn can cause it too.

Was it something about vitamin a? I can't remember. . I have white ducks, white peafowl, and white chickens, and they don't turn yellow, but if they did I would suspect food or a vitamin.

Edited to add:
Too much vitamin a from feeding kale:
https://www.backyardchickens.com/th...yolk-next-to-it.1209393/page-28#post-19339896

 

[chickens really]

I have Healthy Ducks and my two white Hens get yellowish before they molt...