MARIGOLD EXTRACTS AND MAIZE GLUTEN MEAL AS BROILER PIGMENT SOURCES IN MAIZE AND WHEAT-BASED DIETS

A 45-day broiler experiment was conducted with three replicate pens of each sex receiving each dietary regimen. Treatments consisted of two basal diets containing either yellow maize or wheat as the principal energy source, supplemented with maize gluten meal (60%), Cromophyl-Oro, Cromophyl-20, Oro Glo, Florafil A-3, or a 40:60 mixture of Hi Glo and Oro Glo as the source of pigmentation. All groups received a total of 22 mg kg- 1 xanthophyll. An additional treatment in each diet series consisted of the same maize gluten meal sample assigned a value of 80% for pigment availability. Maize diets supported significantly better growth and feed efficiency than wheat-based feeds. Readings of dominant wavelength (DWL), excitation purity (EP) and visual shank color scores were highest for birds that received supplements with a yellow maize diet. Good pigmenting efficiency was displayed by maize gluten meal in either dietary regimen, but Oro Glo and Florafil A-3 had equivalent EP: pigment ratios in wheat diets. Cromophyl-Oro was equivalent to both maize gluten treatments with maize in the basal diet. If the pigment of maize gluten meal was considered to be only 80% (vs. 100%) biologically available, there was a significant response of EP in maize but not wheat diets. Visual evaluations were not significantly different. The choice of basal pigment level and source appeared to have a definite influence on the performance of supplemental pigment sources and should be an important consideration in the commercial evaluation process. © 1990.