FATTY-ACID COMPOSITION OF BIOMPHALARIA-GLABRATA (GASTROPODA, PLANORBIDAE) FED HENS EGG-YOLK VERSUS LEAF LETTUCE

1. Gas-liquid chromatographic studies were done to determine the fatty acid composition of Biomphalaria glabrata snails fed either hen's egg yolk or leaf lettuce for 1 week. 2. Oleic (18:1), palmitic (16:0) and linoleic (18:2) accounted for almost 70% of the fatty acids in the yolk-fed snails; palmitic (16:0), linoleic (18:2), arachidonic (20:4), stearic (18:0), isomers of oleic (18:1), eicosanoic (20:1) and oleic (18:1) comprised about 60% of the fatty acids in the lettuce-fed snails. 3. The percentage composition of palmitic (16:0), oleic (18:1) and linoleic (18:2) acids was significantly greater in yolk- versus lettuce-fed snails; the percentage composition of myristoleic (14:1), heptadecanoic (17:0), heptadecenoic (17:1), linolenic (18:3), eicosanoic (20:1), eicosodienoic (20:2), eicosotrienoic (20:3), arachidonic (20:4), docosapentenoic (20:5), docosadienoic (22:2) and docosatrienoic (22:3) was significantly greater in lettuce- versus yolk-fed snails. 4. Dietary lipids influence markedly the fatty acid composition of Biomphalaria glabrata snails.