Electrophoretic Characterization of Bovine Serum Lipoproteins Throughout Gestation and Lactation

Abstract

The electrophoretic characteristics of the serum lipoproteins of Holstein cows were studied throughout gestation and lactation. The serum lipoproteins were separated into four ultracentrifugal density classes: very low density lipoproteins and chylomicrons ρ < 1.006, low density lipoproteins ρ 1.006 to 1.040, high density lipoproteins sub one ρ 1.040 to 1.063, and high density lipoproteins ρ 1.063 to 1.21. Agarose and polyacrylamide gel electrophoresis were used to analyze the lipoprotein fractions. The electrophoretic patern of blood serum was characterized by a dominant alpha band, a weak beta band, and no detectable pre-beta band. Agarose electrophoresis of the ultracentrifugal density classes demonstrated the association of very low density lipoproteins with pre-beta mobility, low density lipoproteins with beta mobility, and the association of high density lipoproteins sub one and high density lipoproteins with alpha mobility. There was an overlap in density between the lipoproteins demonstrating beta mobility and those with alpha mobility that was unresolvable based on ultracentrifugal separation. Polyacrylamide gel electrophoresis revealed two bands of alpha mobility in the high density lipoproteins sub one throughout lactation, whereas only one alpha band was detected during nonlactation. © 1973, American Dairy Science Association. All rights reserved.