Lipid of Hilsa Fish (Hilsa ilisa)

Bose Institute, 93/1 Acharya Prafulla Chandra Road, Caloutta-700 009

Manuscript received 10 May 1989, revised 15 December 1989, accepted 1 January 1990

The major fatty acids of the flesh-lipid of hilsa fish (Hilsa ilisa) are 16 : 0 (32.0±5.0%), 18 : 0 (8.2±0.5%), 16 : 1 n7 (17.7±1.0%), 18 : 1 n9 (29.6±1.9%), 20 : 5 n3 (4.9±0.5%), 20 : 4 n6 (1.7±0.3%) and 22 : 6 n3 (1.5±0.6%). In this respect this lipid resembles the dietary fat of the Greenland Eskimos. In fish at minimum egg formation, the flesh contains 15.0±0.7% lipid, composed of neutral (88.4±1.7%), phospho-(5.1 ±1 6%) and glyco-(6.5 ± 1.2%) lipids. Lipid contents and lipid-class compositions of the flesh-lipid of hilsa fish at different degrees of egg maturation apparently indicate that the energy required for upstream migration by this fish, for spawning, is supplied by the oxidation of flesh-lipid without any preference for a particular lipid class.