INFLUENCE OF DIET ON FATTY-ACID COMPOSITION OF DEPOT FAT IN WESTERN SANDPIPERS (CALIDRIS MAURI)

Abstract Western Sandpipers (Calidris mauri) have been previously shown to undergo seasonal changes in the fatty acid composition of their fat stores, even though they do not show the marked seasonal variation in diet common to many migratory passerines. We investigated the effect of dietary fatty acid composition on the fatty acid composition of adipose tissue in captive Western Sandpipers by feeding birds experimental diets with different fatty acid composition. In addition, we determined the effect of total percentage of fat content of the diet (5 vs. 10%) on fatty acid composition of depot fat. Birds maintained normal body mass (24–27 g) throughout all experimental treatments. Most adipose fatty acids were sensitive to dietary manipulation to some extent. Changes in fatty acid composition of the diet had the largest effect on adipose tissue composition for the essential polyunsaturated fatty acid linoleate (18:2), whereas it had the least effect for the monounsaturated fatty acid oleate (18:1). The sa...