Giving hens certain natural supplements like paprika or marigold extract makes their egg yolks better at neutralizing harmful oxygen, and this works in two different types of chickens after a month.

Giving certain plant and bacterial supplements to two types of chickens—Rhode Island Reds and Silkies—makes their egg yolks richer in colorful nutrients called carotenoids after a month, and Silkies seem to absorb more of these nutrients than the other chickens.

Silky Fowl chickens naturally have eggs with better antioxidant power than Rhode Island Red chickens, even without any special diet — and it gets even stronger when they eat carotenoids.

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.