Influence of Level of Dietary Fat on Adipose Tissue Lipogenesis and Enzymatic Activity in the Pig

Abstract

One of the foremost goals of swine research is the development of methods to decrease the amount of fat in the pork carcass. We have reported previously (O'Hea, Leveille and Sugahara, 1970; Allee, Baker and Leveille, 1971a; Allee et al., 1971b) that the addition of fat to pig diets induces metabolic responses in adipose tissue resulting in a depression in the capacity for fatty acid synthesis. Although the addition of 12% dietary fat resulted in a marked depression of in vitro fatty acid synthesis, carcass fat was not reduced, presumably because the dietary fat was deposited as such in the carcass. Hill et al. (1958) have reported that lipogenesis in rat liver slices was reduced by feeding as little as 2.5% dietary fat. In the present study we have tested the hypothesis that at a certain minimal level of dietary fat, fatty acid synthesis would be markedly reduced. And, although some of the dietary fat would be deposited, the depression in the conversion of carbohydrate to fat could be of such a magnitude that total body fat might conceivably be reduced.