The distribution of sialic acid in the eggs of original Silky fowl was investigated. The sialic acid contents of the yolk, albumen and the chalaza of a single egg were 205.2, 11.96 and 0.83 mg, respectively. 2. The sialic acid content of the yolk of Silky eggs was 11.5-fold higher than that of a conventional domestic fowl yolk. 3. Sialic acid isolated from Silky yolk was entirely N-acetylneuraminic acid (NeuAc). No N-glycolylneuraminic acid or O-acetyl containing sialic acid was observed. 4. The structure of the major sialylglycan in Silky egg yolk was determined to be a disialyl-biantennary chain in which the NeuAc residues were alpha2-6 linked to glucose. No alpha2-3 linkage was observed. 5. Thus, the Silky fowl's egg provides an excellent source of NeuAc and sialylglycan.
