Controlled experiments suggest that supplemental choline may prevent and alleviate fatty liver in dairy cows. Field studies show increased intake and fat corrected milk production, and decreased incidence of ketosis when cows were fed rumen-protected choline during both close-up period and early lactation. Production responses to dietary supplementation of free niacin are difficult to interpret because there is extensive degradation of niacin in the rumen. Nicotinic acid, a form of niacin, can decrease plasma NEFA concentrations in the bovine under negative energy balance. In the future, nicotinic acid may prove useful in nutritional management of the periparturient dairy cow once a rumen-protected form of nicotinic acid is tested. A rate of nicotinic acid delivery that promotes moderate reduction in NEFA concentrations must first be identified. We also need to define strategies to prevent the occurrence of an exaggerated NEFA rebound once treatment is discontinued. Research is also warranted on potential synergistic effects between nicotinic acid and choline on modulation of lipid metabolism of periparturient cows.