The effect of level of food intake on the incorporation of acetate into lipids and its distribution among various tissues in sheep

Abstract

1. Romney wethers were infused intravenously with [2-¹⁴C]acetate for 5 d during which time they were given, three/group, different amounts of lucerne(Medicago sativa L.) chaff. The groups and the amounts fed were: MS, 700 g but starved during the infusion period; M, 700 g throughout; 1.3 M, 950 g throughout; AL, ad lib. throughout.2. On day 4 of the infusion, the oxygen consumption, and production rate of expired ¹⁴CO₂ were measured. At the end of the infusion, the sheep were killed and the amounts of radioactivity in the lipids of various tissues wre determined.3. Significant differences were present between the specific activities of the tissues. The internal adipose tissues generally had higher specific activities than subcutaneous or intermuscular adipose depots. Although the intramuscular lipid also was highly labelled, the liver had the greatest specific activity.4. Food intake did not significantly affect this pattern of specific activity of labelling of the tissues.5. While most of the total lipid radioactivity was present in adipose tissues, the proportion in the liver increased to 40% during starvation.