Fatty acid positional distribution in egg yolk triglycerides from various avain species

• Published in: Lipids Vol. 8; no. 12; pp. 675 - 681
• Main Authors: Couch, J. R., Saloma, A. E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer‐Verlag 01.12.1973
• ISSN: 0024-4201; 1558-9307
• DOI: 10.1007/BF02531833

The fatty acid composition and distribution in egg yolk triglycerides and phosphatides from the turkey, duck, prairie chicken, bobwhite quail, Japanese quail, and inbred‐hybrid and midget mutant hens were determined after all species had been fed diets of similar fat and fatty acid content for 90 days. Total volk lipids were composed of ca. two‐thirds neutral lipids and one‐third polar lipids. The predominant fatty acids were palmitic and stearic. There were statistically significant differences in the my ristic, palmitic, palmitoleic, linoleic, and linolenic acids in the yolk triglycerides and in the proportion of 16∶1, 18∶0, 18∶2, arachidonic, docosanoic, docosahexaenoic, and tetracosanoic acids in the phosphatides among the various species. Linoleic acid predominantly was linked at the 2‐position in the yolk triglycerides followed by the 20∶4 acid. The 18∶1 acid also was found preferentially at the 2‐position. There was a low level of 18∶2 in the yolk triglycerides and phosphatides from the duck and an especially high level of 20∶4 acid in the phosphatides. The triglycerides in the species studied have essentially the same distribution of fatty acids in the 2‐position. In all the species, the affinity for the fatty acids at the 2‐position is in the following order: 18∶2=20∶4>18∶1 =18∶3>18∶0=16∶1>14∶0>16∶0 Differences observed among the various genera did not appear to follow taxonomic boundaries. The duck has an efficient system for converting 18∶2 into 20∶4 by elongation and desaturation. The prairie chicken apparently has a high requirement for 18∶2 but an inadequate system for its conversion into 20∶4.