Decreased concentration of serum apolipoprotein C-III in cows with fatty liver, ketosis, left displacement of the abomasum, milk fever and retained placenta

Apolipoprotein (apo) C-III is a low molecular mass protein mainly distribut ed in the high-density lipoprotein (HDL) fraction. In cows with postparturi ent diseases such as ketosis, concentrations of cholesterol, phospholipids and apoA-I and the activity of lecithin:cholesterol acyltransfemse, which a re mainly distributed in or functionally associated with HDL, are reduced. The purpose of the present study was to examine whether the serum concentra tion of apoC-III was similarly decreased in the postparturient diseases. Co mpared with healthy controls, the apoC-III concentration was significantly (P<0.01) decreased in cows with fatty liver, ketosis, left displacement of the abomasum, milk fever and retained placenta. Concentrations of apoC-III in the HDL fractions from diseased cows were also lower than in controls. O f the diseased cows, the decreased apoC-III concentration was particularly distinct in cows with milk fever. Increased nonesterified fatty acid and re duced free cholesterol, cholesteryl ester and phospholipid concentrations w ere observed in cows with milk fever, as in the other diseased cows. The de crease in the apoC-III concentration is suggested to be closely associated with the postparturient disorders, in particular with milk fever.