A HORMONAL MECHANISM LINKING LIVER DYSFUNCTION, HYPERKETONEMIA AND REDUCED APPETITE IN EARLY LACTATING DAIRY COWS

We will test the hypothesis that the synthesis of the appetite-suppressing hormone GDF15 is increased in hyperketonemic, early lactating dairy cows. We propose two objectives to test our hypothesis. In objective 1, we will measure indices of GDF15 production in early lactating dairy cows during the course of experimentally induced ketosis and following its resolution. In objective 2, we will measure plasma GDF15 in a large cohort of early lactating dairy cows under commercial conditions and categorized on the basis of BHBA plasma concentration as either normal, subclinically ketotic or clinically ketotic.