Identification of the conjugated linoleic acid isomer that inhibits milk fat synthesis
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- 1 January 2000
- journal article
- research article
- Published by American Physiological Society in American Journal of Physiology-Regulatory, Integrative and Comparative Physiology
- Vol. 278 (1), R179-R184
- https://doi.org/10.1152/ajpregu.2000.278.1.r179
Abstract
Conjugated linoleic acids (CLA) are octadecadienoic fatty acids that have profound effects on lipid metabolism. Our previous work showed that CLA (mixture of isomers) markedly reduced milk fat synthesis. In this study, our objective was to evaluate the effects of specific CLA isomers. Multiparous Holstein cows were used in a 3 × 3 Latin square design, and treatments were 4-day abomasal infusions of 1) skim milk (control), 2) 9,11 CLA supplement, and 3) 10,12 CLA supplement. CLA supplements provided 10 g/day of the specific CLA isomer ( cis-9, trans-11 or trans-10, cis-12). Treatments had no effect on intake, milk yield, or milk protein yield. Only the 10,12 CLA supplement affected milk fat, causing a 42 and 44% reduction in milk fat percentage and yield, respectively. Milk fat composition revealed that de novo synthesized fatty acids were extensively reduced. Increases in ratios of C14:0to C14:1and C18:0to C18:1indicated the 10,12 CLA supplement also altered Δ9-desaturase. Treatments had minimal effects on plasma concentrations of glucose, nonesterified fatty acids, insulin, or insulin-like growth factor-I. Overall, results demonstrate that trans-10, cis-12 CLA is the isomer responsible for inhibition of milk fat synthesis.Keywords
This publication has 17 references indexed in Scilit:
- Conjugated Linoleic Acids Alter Milk Fatty Acid Composition and Inhibit Milk Fat Secretion in Dairy CowsJournal of Nutrition, 1999
- Evidence that the trans‐10,cis‐12 isomer of conjugated linoleic acid induces body composition changes in miceLipids, 1999
- Conjugated Linoleic Acid Decreases Hepatic Stearoyl-CoA Desaturase mRNA ExpressionBiochemical and Biophysical Research Communications, 1998
- Trans-Octadecenoic Acids and Milk Fat Depression in Lactating Dairy CowsJournal of Dairy Science, 1998
- Dietary Conjugated Linoleic Acid Normalizes Impaired Glucose Tolerance in the Zucker Diabetic Fattyfa/faRatBiochemical and Biophysical Research Communications, 1998
- The effect of conjugated linoleic acid on fat to lean repartitioning and feed conversion in pigsCanadian Journal of Animal Science, 1997
- Role of Insulin in the Regulation of Mammary Synthesis of Fat and ProteinJournal of Dairy Science, 1995
- Evaluation of interference by insulin-like growth factor I (IGF-I) binding proteins in a radioimmunoassay for IGF-I in serum from dairy cowsDomestic Animal Endocrinology, 1991
- Positional distribution of fatty acids in the triglyceride classes of milk fatJournal of Dairy Research, 1982
- Lipid extraction of tissues with a low-toxicity solventAnalytical Biochemistry, 1978