Dietary fatty acid and protein effects on plasma and liver lipids

Abstract

Groups of six-day-old female chicks fed semi-synthetic diets containing 14% free fatty acid were evaluated for plasma and liver cholesterol (C), phospholipid (PL), and triglyceride (TG) content. Six different fatty acids (lauric, myristic, palmitic, stearic, oleic and linoleic) were tested at two levels (12.8% and 24.8%) of protein for two different treatment periods (15 and 30 days) in the form of a 3 factorial experimental design. Analysis of variance, F test revealed that treatment duration, dietary protein level, and difference in dietary fatty acid all had significant (p<.05) effects on plasma and/or liver lipid. Compared to 15 days of treatment, 30 day treatment reduced plasma C and PL, but increased liver C and PL. Compared to 12.8% dietary protein, 24.8% protein reduced plasma C and PL, but had no effect on liver lipid. Differences between the individual fatty acids tested were elicited primarily in plasma and liver TG and PL; no significant effect was found in plasma C. Multiple comparison of group means revealed that the significant dietary fat effects were due primarily to linoleic and palmitic acid in plasma, and to linoleic and lauric acid in liver.