Tough Yolks?

[JillnJack]

Hi! Wondering if anyone has or knows why sometimes egg yolks are quite firm and tough. Whites are normal but the yolks are so firm that you have to use a blender or mixer to beat the egg yolk down.

When it first happened we figured the eggs had gotten too cold. But our temperatures haven't been freezing for a while already and our egg fridge is set to the "warmest" fridge temp possible.

They get a regular hen feed but we toss in a lot of food scraps and the occasionally they get beef liver. Would too much protein in their diet affect the yolk quality?

Thanks in advance!

 

[aart]

Some are just tougher than others, it's an individual birds thing.
Has nothing to do with feed or temps.