Updates in transition cow health and nutrition

Abstract

Transition cow nutritional management strategies have evolved significantly over the past 10 years and continue to evolve. Management of subclinical hypocalcemia is important to support high milk yield, excellent reproduction, and decrease subclinical disease. Feeding anionic diets before calving, perhaps using more aggressive strategies, improves blood calcium status post-calving and increases post-calving dry matter intakes and milk yield. Controlling energy intake before calving improves postpartum energy balance and decreases subclinical ketosis; feeding adequate metabolizable protein before calving helps maintain high milk yield after calving. Excellent feeding management (managing chop length of bulky forage and moisture of the (total mixed ration) TMR) of transition rations is critical for on-farm success; many dairy farms have opportunities for improved feeding management. There may be interactions of starch levels pre- and post-calving; cows fed low starch pre-calving rations should be fed lower starch diets after calving, whereas cows fed moderate starch rations pre-calving can likely be fed starch levels more typical of high starch cow rations after calving. Furthermore, there may be opportunities to combine higher fermentability with higher bulk in fresh cow rations to improve feed intakes after calving, as well as to more critically consider metabolizable protein and amino acid formulation of the fresh diet.