Pineal gland lipid characterization in the seven-week-old cockerel (Gallus domesticus).

The composition of pineal gland lipid was characterized in young cockerels. The total pineal lipid was 159.7 microgram, which was equivalent to 3.0 and 14.1% of fresh and dry tissue weight, respectively. The major phospholipids were phosphatidyl choline (63.1%), phosphatidyl ethanolamine (16.1%), and sphingomyelin (14.7%). Palmitic, stearic, oleic, and arachidonic acids composed 27.9%, 19.4%, 15.8%, and 13.7% of the phospholipid fatty acid fraction, respectively. Free fatty acids (38.4%), cholesterol (17.6%), and cholesterol ester (17.2%) comprised the major fraction of neutral lipids, while the predominant neutral lipid fatty acids were palmitic (26.0%) and oleic (23.8%). The percentage of wet tissue weight that is lipid in the pineal is considerably less when compared to brain cortex or retina. When chickens are compared to several mammalian species, there is little difference in percent lipid per milligram pineal tissue, but definite differences exist in the percentage of various lipid classes.