Early lactation is a challenging and stressful period for dairy cows. Several metabolic diseases happen during this period, which is characterized by a negative energy balance and metabolic imbalance. Most of these issues start as close-ups and result from faulty management and/or feeding practices. Over-conditioning cows during the dry period allows them to mobilize more fat after calving and make them prone to metabolic diseases early in the lactation.
Recently calved cows have reduced appetite and greater energy demands due to the sudden increased milk production. This results in greater fat mobilization and increased hepatic triacylglycerol deposits predisposing to what is known as fatty liver and even ketosis. There are also negative effects of excessive fat mobilization on the metabolism and the immune system (neutrophils). Blood neutrophil phagocytosis has been shown to decrease 14 days post calving in cows overfed during the dry period. Choline helps with lipid transport from the liver in very low-density lipoproteins (VLDL).