High-carotenoid biofortified maize is an alternative to color additives in poultry feed

Abstract

Skin color in poultry is achieved by the addition of natural or synthetic pigments to feed. Crops used routinely in feed formulations offer an alternative cost-effective strategy to replace color additives if they are biofortified with sufficient levels of carotenoids. We tested the hypothesis that high-carotenoid (HC) maize, which was genetically engineered to accumulate high levels of β‐carotene, lutein and zeaxanthin in the endosperm, can replace carotenoid additives in poultry feed by performing two feeding trials using diets incorporating different maize lines with diverse carotenoid compositions: control (wild-type M37W, the parental line), HC, and standard yellow commercial maize supplemented with color additives (marigold flowers and red paprika extracts). The effects of dietary treatments on growth performance, health parameters, color evolution and carotenoid distribution were determined. We found that chickens fed on the HC diet grew normally and developed similar pigmentation to animals fed on a commercial diet supplemented with color additives, although yellowness was significantly higher in the commercial diet due to the high concentration of yellow xanthophylls. Lightness scores in chickens fed on the control, HC and commercial diets were 45.88±1.31, 44.32±1.10 and 44.29±0.99, respectively, in breast muscle, and 51.62±1.33, 49.66±0.96 and 50.10±1.16, respectively, in thigh muscle. Redness scores in chickens fed on the control, HC, and commercial diets were 0.36±0.26, 3.25±0.29 and 3.58±0.29, respectively, in breast muscle, and 1.28±0.37, 4.79±0.39 and 4.85±0.34, respectively, in thigh muscle. Yellowness scores in chickens fed on the control, HC, and commercial diets were 2.45±0.47, 7.61±0.64 and 9.66±0.73, respectively, in breast muscle, and 3.38±0.64, 10.00±1.10 and 12.64±0.97, respectively, in thigh muscle. High-carotenoid maize is therefore a cost-effective alternative to feed supplementation in the poultry industry.