Composition of lipids from the glands of the external ear canal of the adult chicken.

Six classes of neutral lipids, i.e. triacylglycerol (TG), free fatty acids (FFA), monoester waxes (MW), free- and esterified sterols (FST and SE), and squalene (SQ) were identified by thin layer chromatography of the lipid materials extracted separately from the secretion as well as from the isolated whole glands present in the skin of the floor of the external ear canal of the domestic fowl. Secretory lipids contained considerable proportions of MW fractions (17.03%), TG (22.23%), and SQ (14.66%), while TG was the major component (41.10%) in the lipids from the isolated glands. Polar lipids, which comprised about 16-20% of total glandular lipids, were shown to be composed primarily of sphingomyelin.