Relationship of fat metabolism to health and performance in dairy cattle

Abstract

Rapid mobilization of adipose fat accompanied by hyperketonemia and fatty liver (FL) is extremely common in peripartum dairy cows. Previous reports indicate an inverse relationship between liver fat concentration and disease resistance. Such a relationship could be mediated through a hyperketonemic suppression of cellular immunity, altered serum lipoprotein concentrations or other effects associated with negative energy balance. Appetite reduction may be associated with fat mobilization and this could be due to FL and the direct effects of the liver on food-intake centers of the brain. Reproductive efficiency is reduced in association with FL; such an association could be due to FL-associated hypolipoproteinemia and the need for serum lipoproteins to support maximal progesterone synthesis by the ovary.