Summary. The It is concluded that ketonemia was enhanced in late gestation, particularly with restricted feeding or in fasted animals ; this enhancement was partly related to the increase of plasma NEFA concentrations and partly to the enhancement of hepatic ketogenesis in the mothers. The fact that the rate of hepatic ketogenesis was increased equally with butyrate and oleate indicated that it could not be explained by a modification of acylcarnitine transferase activity as butyrate directly crosses the mitochondrial membrane without using this pathway.Introduction.