The objectives of this thesis were to 1) evaluate the impact of supplementing omega-3 (n3) fatty acids (FA) using calcium salts enriched in fish oil (Ca-FO) during the early postpartum period on the degree and resolution of inflammation using an induced acute inflammation model, and 2) test whether these effects were from an increased energy density of the diet or were due to the effects of n3 FA on immune cell biology. Supplementing Ca-FO was reflected by changes in the FA composition of plasma, milk, and peripheral blood leukocytes. Increased basal and endotoxin-induced concentrations of IFNγ and MIP1ɑ, reduced body temperature response to the endotoxin challenge, and greater rumen activity one day after induced inflammation suggest that supplementation with n3 FA can modulate postpartum inflammation.