A HIGH OMEGA-3-FATTY-ACID DIET ALTERS FATTY-ACID COMPOSITION OF HEART, LIVER, KIDNEY, ADIPOSE-TISSUE AND SKELETAL-MUSCLE IN SWINE

The fatty acid profiles and total lipid contents of two skeletal muscles, adipose tissue, heart, liver and kidney of swine fed a diet rich in omega 3 (n-3) fatty acids (i.e., 5% fish oil) was investigated. These values were compared to those determined for animals which were fed an equal caloric diet low in n-3 fatty acids (i.e., 5% coconut oil). All supplementations were given over a 13-week period. The lipids were extracted with chloroform-methanol, transesterified and the relative fatty acid methylesters concentrations were determined using capillary gas chromatography. The fish oil diet significantly enhanced the relative amounts of n-3 fatty acids (i.e., eicosapentaenoic acid and docosahexaenoic acid) in all tissues examined. In the heart, liver and kidney, the increases in n-3 fatty acids were compensated by decreases primarily in arachidonic acid, but in the other tissues the contents of lauric and myristic acids were also reduced. In general, the n-3 fatty acid contents were 40-165% higher in the animals fed the fish oil. Supplementation of n-3 fatty acids in swine induced a significant incorporation of these fatty acids throughout the body, however the extent of this incorporation differed between tissues perhaps due to tissue-specific metabolic pathways.