Endogenous Synthesis of cis-9, trans-11 Conjugated Linoleic Acid in Dairy Cows Fed Fresh Pasture
Open Access
- 1 February 2004
- journal article
- Published by American Dairy Science Association in Journal of Dairy Science
- Vol. 87 (2), 369-378
- https://doi.org/10.3168/jds.s0022-0302(04)73176-8
Abstract
New Zealand Holstein-Friesian cows (n = 4) were used to quantify the importance of endogenous synthesis of cis-9, trans-11 conjugated linoleic acid (CLA) via Delta(9)-desaturase in cows fed a fresh pasture diet. The experiment was a 4 x 4 Latin square design with treatments arranged in a 2 x 2 factorial. Treatments lasted 4 d and were pasture only, pasture plus sterculic oil, pasture plus sunflower oil, and pasture plus sunflower oil plus sterculic oil. Abomasal infusion of sterculic oil inhibited Delta(9)-desaturase and decreased the concentration of cis-9, trans-11 CLA in milk fat by 70%. Using the changes in cis-9 10:1, cis-9 12:1 and cis-9 14:1 to correct for incomplete inhibition of Delta(9)-desaturase, a minimum estimate of 91% of cis-9, trans-11 CLA in milk fat was produced endogenously in cows fed fresh pasture. Dietary supplementation of a pasture diet with sunflower oil increased the proportion of long chain fatty acids in milk fat; however, the increase in vaccenic acid concentration was small (18%) and there was no increase in cis-9, trans-11 CLA concentration. Overall, results show that endogenous synthesis is responsible for more than 91% of the cis-9, trans-11 CLA secreted in milk fat of cows fed fresh pasture. However, the failure of plant oil supplements to increase the concentration of cis-9, trans-11 CLA in milk fat from pasture-fed cows requires further investigation.Keywords
This publication has 35 references indexed in Scilit:
- The Biology of Conjugated Linoleic Acids in RuminantsPublished by Taylor & Francis ,2003
- The role of Δ9-desaturase in the production of cis-9, trans-11 CLAThe Journal of Nutritional Biochemistry, 2001
- Dietary Influences on Bovine Milk cis‐9,trans‐11‐Conjugated Linoleic Acid ContentJournal of Food Science, 1997
- Lipid metabolism in the rumenPublished by Springer Nature ,1997
- One-Step Lipid Extraction and Fatty Acid Methyl Esters Preparation from Fresh Plant TissuesAnalytical Biochemistry, 1993
- Lipid extraction of tissues with a low-toxicity solventAnalytical Biochemistry, 1978
- Stearyl-CoA desaturase of bovine mammary microsomesArchives of Biochemistry and Biophysics, 1973
- The effect of intravenous infusions of sterculic acid on milk fat synthesisBritish Journal of Nutrition, 1972
- The desaturase activity of goat and sow mammary tissueComparative Biochemistry and Physiology, 1970
- A TWO‐STAGE TECHNIQUE FOR THE IN VITRO DIGESTION OF FORAGE CROPSGrass and Forage Science, 1963