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Changes in the conjugated linoleic acid content of milk from dairy cows throughout the year
Published online by Cambridge University Press: 27 February 2018
Abstract
Conjugated linoleic acid (CLA) is a naturally occurring anticarcinogen found in dairy products which is produced in the rumen as an intermediate in the biohydrogenation of polyunsaturated fatty acids by the bacteria Butyrivibrio fibrivsolvens. An experiment was conducted to examine the changes in CLA concentration in bovine milk throughout the year. 338 milk samples were taken from the University of Nottingham's commercial dairy herd between December 1997 and March 1999. All animals followed the same dietary regime throughout the study. Samples were analysed for fat and CLA content. Morning and evening samples were pooled to calculate daily fat and CLA concentrations and yields. There was a small variation in milk yield (P<0.05) whereas CLA content and yield varied considerably (P<0.001) throughout the year (CLA = 0.91 to 2.81 mg/g of fat). The highest concentrations were found during the summer months when the cows were mainly eating fresh grass as opposed to conserved forages. Fat content and yield followed by the month were the predominant factors affecting CLA output. Results indicate that, if required, CLA in milk could be increased through suitable dietary management practices.
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References
References AOAC
1990. AOAC Official Methods of Analysis: Food Composition; Additives; Natural Contaminants Volume Two: 812–814.Google Scholar
Doll, R.
1992. The lessons of life – keynote address to the Nutrition and Cancer Conference. Cancer Research
52:s2024–s2029.Google Scholar
Ha, Y.L., Grimm, N.K. and Pariza, M.W.
1987. Anticarcinogens from ground beef: heat altered derivatives of linoleic acid. Carcinogenesis
8: 1881–1887.CrossRefGoogle ScholarPubMed
Ha, Y.L., Storkson, J. and Pariza, M.W.
1990. Inhibition of benzo(a)pyrene-induced mouse forestomach neoplasia by conjugated dienoic derivatives of linoleic acid. Cancer Research
50: 1097–1101.Google ScholarPubMed
Jiang, J., Bjoerck, L., Fonden, R. and Emanuelson, M.
1996. Occurrence of conjugated Cis-9, trans-11-octadecadienoic acid in bovine milk: Effects of feed and dietary regimen. Journal of Dairy Science
79: 438–445.CrossRefGoogle ScholarPubMed
Kelly, M.L., Berry, J.R., Dwyer, D.A., Griinari, J.M., Chouinard, P.Y., Van Amburgh, M.E. and Bauman, D.E.
1998. Dietary fatty acid source affects conjugated linoleic acid concentrations in milk from lactating cows. Journal of Nutrition
128: 881–885.CrossRefGoogle Scholar
Kepler, C.R. and Tove, S.B.
1967. Biohydrogenation of unsaturated fatty acids III. Purification and properties of a linoleate cis-12, trans-11 isomerase from Butyrivibrio fibrivsolvens
. Journal of Biological Chemistry
242: 5686–5692.CrossRefGoogle Scholar
Lin, H., Boylston, T.D., Chang, M.J., Luedecke, L.O. and Shultz, T.D.
1995. Survey of the conjugated linoleic acid contents of dairy products. Journal of Dairy Science: 2358–2365.CrossRefGoogle ScholarPubMed
Lough, A.K. and Anderson, L.J.
1973. Effect of ensilage on the lipids of pasture grass. Proceedings of the Nutrition Society
32: 61A–62A.Google Scholar
Parodi, P.W.
1994. Conjugated Linoleic Acid – an anticarcinogenic fatty acid present in milk fat. Australian Journal of Dairy Technology
49: 93–97.Google Scholar
Parodi, P.W.
1997. Cows’ milk fat components as potential anticarcinogenic agents. Journal of Nutrition
127: 1055–1060.CrossRefGoogle ScholarPubMed