Abstract DARK colored yolks in eggs were first reported by Roberts and Rice (1891) who described this condition in eggs produced by hens fed cottonseed meal. Altschul et al. (1958) reported eggs from hens fed cottonseed meal usually appear normal when first laid; but when stored for a month or longer, yolk discoloration develops. They further stated that the nutritive value of such eggs is probably not impaired in any way, but their appearance makes them unsalable. Work has been done by Schaible et al. (1934), Heywang et al. (1954), Grau et al. (1955), Cavanagh (1957b) and Dechary et al. (1957) to eliminate the components in cottonseed meal which have a deleterious effect when included in rations of non-ruminants and poultry. Wamble (1958) and Evans et al. (1957) also reported the progress made in eliminating the color problems in stored eggs previously associated with cottonseed meal in the rations of laying…