Skin Color Evaluation in Broilers Fed Natural and Synthetic Pigments. the Nutritional Contributions of Animal Prod- Ucts to the Us Diet -the Usda Food Pyramid and Di- Etary Guidelines

Broiler carcass skin color is important in the USA and Mexico. Because pigments are expensive, this study evaluated the use of natural and synthetic pigments in broiler diets at commercial levels. In two trials, 280 chicks were randomly distributed (20 birds each) into seven treatments according to the pigment class (natural or synthetic) and the inclusion level (ppm of pigments) of yellow (apoester) and red (canthaxanthin) pigments. Two treatments were designed to mimic current commercial practices in the USA and Mexico. The treatments were: control (no pigment); natural-low level, natural-high level, synthetic-low level, synthetic-high level, a common USA level, and a natural-synthetic blend used in Mexico. Diets were started at week 3 and feed consumption, body weight, skin color, and blood pigment level were evaluated weekly from weeks 3 to 7. At 49 d of age the birds were processed and skin color was measured after picking and chilling. The natural pigments had consistently greater skin b∗ values (yellowness) than the synthetic pigments. The high levels produced greater skin b∗ values than the low levels, regardless of source. The synthetic pigments had a slower increase in skin b∗ but reached the same level as the natural-low by 7 wks. There was no difference in skin a∗ values (redness) due to pigment source or level or the age of the bird. By 7 wks, all pigment sources approached plateau levels in the blood but the synthetic pigment diet had higher blood levels of both yellow and red pigments than the natural pigment diets. Processing intensified skin yellowness and reduced skin redness. These data suggest that natural pigments were more efficient at increasing skin yellowness and that there were only small differences between high and low levels for each pigment source. This may allow a reduction in pigment use and feed cost to achieve the same skin acceptance by the consumer. color, pigment, carotenoid, skin, broiler