Location: Forage and Livestock Production ResearchTitle: Differences in fatty acid composition of milk fat from ruminants of different species and breeds Author
Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 10/15/2009
Publication Date: 11/8/2009
Citation: Peng, Y.S., Brown, M.A., Wu, J.P. 2009. Differences in fatty acid composition of milk fat from ruminants of different species and breeds [abstract]. Journal of Animal Science. Paper No. T274. Available: http://www.asas.org/pacificrim09/ASASCAAV-2009-AbstractBook.pdf. Interpretive Summary: Abstract only.
Technical Abstract: Milk has an important dietary role in rural households in western China and the fatty acid profile of milk is of interest because of the role of different fatty acids in human nutrition. Fatty acid profiles of milk from goats (n=12), Holstein cows (n=12), and yaks (n=12) were compared in one study to evaluate differences in fatty acid profiles when the species were managed according to conventional practices. Yak were managed entirely on pasture, goats were grazed on pasture but lotted at night and fed a supplement, and Holstein cows were managed in drylot and fed corn silage and protein supplement. A second study was done comparing fatty acid profiles of milk from Chinese yellow cattle (n=12) with milk from Simmental cows (n=12) where the Chinese yellow cattle and Simmental were managed on the same farm and fed corn silage and protein supplement. In the first experiment, percent short-chained fatty acids in goats were greater (P < 0.01) than Holstein, especially C8 and C10, which have been implicated in milk flavor. Percent C18 was less (P < 0.01) in goats than Holstein or yak. Percent conjugated linoleic acid isomers (C18:3c9,t11 and C18:3c9, c12, c15) were greater (P < 0.01) in yak (1.47 and 1.55%) than Holstein (0.60 and 0.48%) and goat (1.14 and 0.55%), which probably reflects both species differences and differences in nutritional management. Additionally, the ratio of omega 3 to omega 6 fatty acids was greater (P < 0.01) in yak than goats or Holstein. In the second experiment, percent C18 was greater in Chinese yellow cattle than Simmental cattle but percent conjugated linoleic acid (C18:3c9,t11) was greater (P< 0.01) in milk from Simmental cattle compared to Chinese yellow cattle. Improvements in human nutrition associated with beneficial fatty acids should be achievable through selection of milk from appropriate breeds, species, and management.