Deposition of Individual Carotenoids in Avian Skin

Abstract

Abstract In a comparison of the skin-pigmenting efficiency of isolated carotenoids during a five week feeding period with male chicks, the carotenediols, lutein and zeaxanthin, were superior to all other materials tested. While lutein was deposited to the same extent as zeaxanthin, the depth of color produced was slightly less intense. Neolutein was nearly as effective as trans-lutein. Yellow corn selections in which either lutein or zeaxanthin was preponderant produced deposits similar to those of the purified pigments. Dietary fat (2% or 10% lard) improved pigmenting efficiency. In a comparison of mono-carotenols, cryptoxanthin was deposited about twice as efficiently as was zeinoxanthin. β-Carotene was ineffective. Synthetic β-apo-8′-carotenal was nearly half as effective as the carotenediols and produced a normal color; canthaxanthin was more efficient but produced an unnatural color. The carotenols deposited in the skin were found to be largely in the ester form. The carotenol fed was in each case the predominant pigment found in the skin.