HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Palmquist, D. L. Articles by Mattos, W. Search for Related Content PubMed Articles by Palmquist, D. L. Articles by Mattos, W.

Turnover of Lipoproteins and Transfer to Milk Fat of Dietary (1-Carbon-14) Linoleic Acid in Lactating Cows¹

Department of Dairy Science, Ohio Agricultural Research and Development Center, Wooster 44691

ABSTRACT

Chylomicra and very low density lipoproteins labeled with 1-Carbon-14 linoleic acid were isolated from thoracic duct lymph of a calf fed the labeled fatty acid and injected into lactating cows fed a control diet of hay, grain, and corn silage (Experiments 1 and 3) or a high grain-restricted roughage diet (Experiment 2). Fractional removal rates (min^–1) of lipoprotein fractions were .429, .538, and .280 for very low density lipoproteins (density less than 1.02 g/ml) and .0116, .00186, and .00610 for low density lipoproteins (density 1.04–1.08 g/ml). Particle size of injected material influenced rate of removal of very low density lipoproteins whereas removal of low density lipoproteins was slowest in the cow fed a high grain diet.

In two additional experiments, labeled linoleic acid was placed postruminally through a rumen fistula. Total recovery of radioactivity and curve analysis of radioactivity disappearance in the milk fat of all five trials were used to model lipoprotein metabolism. The model suggests that 76% of absorbed lipid is taken up directly by the mammary gland and that 44% of milk fat is of direct dietary origin.

¹ Approved as Journal Article No. 141–77, Ohio Agricultural Research and Development Center, Wooster 44691.

This article has been cited by other articles:

				A. T. M. van Knegsel, H. van den Brand, E. A. M. Graat, J. Dijkstra, R. Jorritsma, E. Decuypere, S. Tamminga, and B. Kemp Dietary Energy Source in Dairy Cows in Early Lactation: Metabolites and Metabolic Hormones J Dairy Sci, March 1, 2007; 90(3): 1477 - 1485. [Abstract] [Full Text] [PDF]

				S. L. Lake, T. R. Weston, E. J. Scholljegerdes, C. M. Murrieta, B. M. Alexander, D. C. Rule, G. E. Moss, and B. W. Hess Effects of postpartum dietary fat and body condition score at parturition on plasma, adipose tissue, and milk fatty acid composition of lactating beef cows J Anim Sci, March 1, 2007; 85(3): 717 - 730. [Abstract] [Full Text] [PDF]

				B. A. Corl, S. T. Butler, W. R. Butler, and D. E. Bauman Short communication: Regulation of milk fat yield and fatty acid composition by insulin. J Dairy Sci, November 1, 2006; 89(11): 4172 - 4175. [Abstract] [Full Text] [PDF]

				S. M. Carroll, E. J. DePeters, and M. Rosenberg Efficacy of a Novel Whey Protein Gel Complex to Increase the Unsaturated Fatty Acid Composition of Bovine Milk Fat J Dairy Sci, February 1, 2006; 89(2): 640 - 650. [Abstract] [Full Text] [PDF]