Impact of dietary soybean oil versus medium-chain triglycerides on plasma fatty acids in goats

The influence on lipid metabolism of dietary soybean oil with 52.6% linoleic acid (C18:2n-6), was studied in 2-year-old, male-castrated Dutch white goats.Amedium-chain triglycerides-product (MCT) containing 48.9% caprylic (C8:0) and 41.0% capric acid (C10:0)was used as control oil. Six goats were fed the diets containing either soybean oil orMCTaccording to a 21× 21 days cross-over design. The rations contained about 15% crude fat in the dietary dry matter. The soybean oil diet significantly (P < 0.05) increased the absolute amount of linoleic acid in plasma lipids. The plasma contents of heptadecanoic acid (C17:0) and heptadecenoic acid (C17:1) were decreased by feeding the soybean oil diet (P < 0.05). The fatty acid composition of red blood cells was not differently affected by the dietary fats. Dietary soybean oil versus MCT significantly (P < 0.05) increased plasma total cholesterol by 47%, HDL cholesterol by 50% and phospholipids by 39%, but left plasma triglycerides and non-esterified fatty acids unchanged (P > 0.05). This study provides evidence that dietary linoleic acid can escape from biohydrogenation in the rumen of goats and shows that the type of dietary fat has amarked impact on lipid metabolism in goats. © 2003 Elsevier Science B.V. All rights reserved