Age-Class Differences in Lipids from the Paracloacal Glands of the American Alligator (Alligator mississippiensis)

Abstract

Abstract The paracloacal gland secretions of immature and adult American alligators (Alligator mississippiensis) from Louisiana were analyzed by gas chromatography/mass spectrometry and nuclear magnetic resonance spectroscopy to investigate age-class differences in lipid composition. The secretions of both immature and adult alligators contain saturated C14 and C16 free fatty acids and decyl, undecyl, dodecyl, tetradecyl, and hexadecyl acetates. Com­pounds observed only in immature alligators include dodecanoic acid, C12 and C14 alcohols, C10-C14 butanoates, an array of C8-C18 3-methylbutanoates, C12- C15 hexanoates, C12 and C14 octanoates, a C12 decanoate, C10-C14 dodecanoates, C10- C16 tetradecanoates, C12 and C14 hexadecanoates, a C12 octadecanoate, and a diterpene hydrocarbon identified as (E ,E )- 7,11,15-trimethyl-3-methylenehexadeca-1,6,10,14-tetraene (β-springene). Compounds observed only in adults include several C7-C16 free fatty acids and certain C10- C18 acetates. The age-class differences we observe in the paracloacal gland lipids of alligators from Louisiana are similar to those previously reported for alligators from Texas.