Variations in serum-magnesium and in the partition of serum-calcium in normal parturition and in milk fever

Abstract
Variations were studied in the blood of [apparently 9] dairy cows at parturition and in milk fever and for certain doubtful cases. Acute symptoms of milk fever were preceded by a much steeper fall than usual in total serum-Ca before and at calving and rose only when there was a simultaneous low level of both the BaSO4 adsorbable Ca complexes and the non-adsorbable Ca. The fall in adsorbable Ca complexes accounts for the major part of the fall in total serum-Ca in cases of milk fever. Serum-Mg and serum-Ca rose together during recovery from milk fever.