Postpartum dairy cows experience a nutrient deficit that coincides with damaging inflammation and infectious disease, resulting in reduced animal well-being and production, increased antimicrobial use, and premature culling. Availability and metabolism of nutrients alters immune function and inflammatory profile in other species. We lack a basic understanding of immunometabolism in the bovine species, limiting our ability to resolve postpartum immune dysfunction. We aim to elucidate how nutrient availability (deficit or supplementation) can alter immune function in dairy cows during the transition to lactation. Specifically we propose to evaluate the effects of therapeutic use of calcium on magnitude and resolution of postpartum inflammation.

Our central hypothesis is that activated bovine immune cells exert differential nutrient preferences and that altering nutrient availability can modulate transition cow immune dysfunction. To address this, our objectives are to: 1) Quantify nutrient use, cytokine profile, and measure immune cell function of ex vivo stimulated leukocytes, and 2) Determine whether calcium supplementation alters the magnitude, duration, and resolution of the in vivo inflammatory response in postpartum cows.