Farmers add paprika and marigold to chicken food to make egg yolks look more orange because people think those eggs are healthier—even if they're not.

Giving Japanese quails food with a little bit of paprika or marigold extract makes their egg yolks more colorful, which people usually like better.

Feeding quails natural plant pigments from paprika and marigolds might help keep their eggs fresher for longer by slowing down changes inside the egg as it's stored.

Giving older laying hens paprika extract in their food makes their egg yolks more colorful, especially in Rhode Island Reds — they respond more than Silky Fowl hens when given a higher dose.