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Seasonal variations in the fatty acid profile of milk from yaks grazing on the Qinghai-Tibetan plateau

Published online by Cambridge University Press:  14 October 2013

Luming Ding
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, Institute of Arid Agroecology, School of Life Sciences, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Yupeng Wang
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, Institute of Arid Agroecology, School of Life Sciences, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Michael Kreuzer
Affiliation:
ETH Zurich, Institute of Agricultural Sciences, Universitaetstrasse 2, 8092 Zurich, Switzerland
Xusheng Guo
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, Institute of Arid Agroecology, School of Life Sciences, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Jiandui Mi
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, Institute of Arid Agroecology, School of Life Sciences, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Yujiao Gou
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, College of Pastoral Agriculture Science and Technology, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Zhanhuan Shang
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, College of Pastoral Agriculture Science and Technology, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Ying Zhang
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, College of Pastoral Agriculture Science and Technology, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Jianwei Zhou
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, College of Pastoral Agriculture Science and Technology, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Hucheng Wang
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, College of Pastoral Agriculture Science and Technology, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
Ruijun Long*
Affiliation:
State Key Laboratory of Grassland Agro-Ecosystem, College of Pastoral Agriculture Science and Technology, International Centre for Tibetan Ecosystem Management, Lanzhou University, Lanzhou 730000, PR China
*
*For correspondence; e-mail: longrj@lzu.edu.cn

Abstract

An experiment was conducted to study the seasonal changes in the fatty acid profile of milk from yaks (Bos grunniens) when kept at altitudes of 3000 m above sea level (a.s.l.) and higher. Data and samples were collected in summer (July), autumn (September), winter (November) and spring (March) from ten lactating yaks (four in spring). The yaks grazed pastures adjacent to the farm building throughout the year. In spring only they received 0·6 kg crop by-products per day (dry matter basis). Fresh alpine grasses, available in summer and autumn, showed high concentrations of α-linolenic acid (46–51 g/100 g lipids) compared with the dry, yellow vegetation of winter and spring (16 g/100 g lipids). In autumn and summer, the milk fat had higher concentrations of polyunsaturated fatty acids than in winter. These polyunsaturated fatty acids were comprised of vaccenic acid, rumenic acid and α-linolenic acid, which are all considered beneficial to human health. The rare fatty acid, γ-linolenic acid, was also detected in yak milk, especially in the milk obtained in spring. The results suggest that yak milk, which is the most important basic food of the Tibetan herders, has the most favourable fatty acid profile when yaks grazed green pasture, which also corresponds to the period of highest milk production.

Type
Research Article
Copyright
Copyright © Proprietors of Journal of Dairy Research 2013 

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References

Al Zahal, O, Or-Rashid, MM, Greenwood, SL, Douglas, MS & McBride, BW 2009 The effect of dietary fiber level on milk fat concentration and fatty acid profile of cows fed diets containing low levels of polyunsaturated fatty acids. Journal of Dairy Science 92 11081116Google Scholar
AOAC 1990 Official Methods of Analysis, 15th edition. Arlington, VA, USA: Association of Official Analytical ChemistsGoogle Scholar
Banni, S, Carta, G, Contini, MS, Angioni, E, Deiana, M, Dessi, MA, Melis, MP & Corongiu, FP 1996 Characterization of conjugated diene fatty acids in milk, dairy products, and lamb tissues. Journal of Nutritional Biochemistry 7 150155CrossRefGoogle Scholar
Boufaïed, H, Chouinard, PY, Tremblay, GF, Petit, HV, Michaud, R & Bélanger, G 2003 Fatty acids in forages. I. Factors affecting concentrations. Canadian Journal of Animal Science 83 501511Google Scholar
Couvreur, S, Hurtaud, C, Lopez, C, Delaby, L & Peyraud, JL 2006 The linear relationship between the proportion of fresh grass in the cow diet, milk fatty acid composition, and butter properties. Journal of Dairy Science 89 19561969Google Scholar
Demeyer, D & Doreau, M 1999 Targets and procedures for altering ruminant meat and milk lipids. Proceedings of the Nutrition Society 58 593607CrossRefGoogle ScholarPubMed
Dhiman, TR, Anand, GR, Satter, LD & Pariza, MW 1999 Conjugated linoleic acid content of milk from cows fed different diets. Journal of Dairy Science 82 21462156Google Scholar
Ding, LM & Long, RJ 2010 The use of herbage N-alkanes as markers to estimate the diet composition of yaks on the Qinghai-Tibetan plateau. Asian-Australasian Journal of Animal Sciences 23 6167CrossRefGoogle Scholar
Ding, LM, Long, RJ, Yang, YH & Xu, SH 2007 Behaviour responses by yaks, in different physiological states (lactating, dry or replacement heifer), when grazing natural pasture in spring (dry and germinating) season of Qinghai-Tibetan plateau. Applied Animal Behaviour Science 108 139250CrossRefGoogle Scholar
Guo, XS, Long, RJ, Kreuzer, M, Ding, LMShang, ZH, Zhang, Y, Yang, Y & Cui, GX 2012 Importance of functional ingredients in yak milk derived food on health of Tibetan nomads living under high altitude stress: a review. Critical Reviews in Food Science and Nutrition (doi: 10.1080/10408398.2011.584134), latest articlesGoogle Scholar
Hays, FL, Bianca, JB & Näf, F 1978 Effects of exercise on young and adult cattle at low and high altitude. International Journal of Biometeorology 22 147158Google Scholar
Hermansen, JE, Jonsbo, F & Andersen, JO 1995. On the transfer of gamma-linolenic acid into milk-fat and its possible eclongation to arachidonic-acid by cows. Milchwissenschaft – Milk Science International 50 36Google Scholar
Jensen, RG, Ferris, M & Lammi-Keefe, CJ 1991 Symposium: milk fat composition, function and potential for change. Journal of Dairy Science 74 32283243CrossRefGoogle Scholar
Kelly, ML, Kolver, ES, Bauman, DE, Van Amburgh, ME & Muller, LD 1998 Effect of intake of pasture on concentrations of conjugated linoleic acid in milk of lactating cows. Journal of Dairy Science 81 16301636CrossRefGoogle ScholarPubMed
Kgwatalala, PM, Ibeagha-Awemu, EM, Mustafa, AF & Zhao, X 2009 Stearoyl-CoA desaturase 1 genotype and stage of lactation influences milk fatty acid composition of Canadian Holstein cows. Animal Genetics 40 609615Google Scholar
Khanal, RC & Olson, KC 2004 Factors affecting conjugated linoleic acid (CLA) content in milk, meat, and egg: a review. Pakistan Journal of Nutrition 3 8298Google Scholar
Khiaosa-ard Siepmann, R, Kreuzer, M & Leiber, F 2012 Influence of dietary precursor fatty acid concentrations on linolenic and vaccenic acid concentrations in cow's milk: a meta-analysis. Proceedings of the Society of Nutrition Physiology 21 72Google Scholar
Leiber, F, Kreuzer, M, Nigg, D, Wettstein, H-R & Scheeder, MRL 2005 A study on the causes for the elevated n-3 fatty acids in cows’ milk of alpine origin. Lipids 40 191202Google Scholar
Liu, HN, Ren, FZ, Jiang, L, Ma, ZL, Qiao, HJ, Zeng, SS, Gan, BZ & Guo, HY 2011 Short communication: fatty acid profile of yak milk from the Qinghai-Tibetan Plateau in different seasons and for different parities. Journal of Dairy Science 94 17241731CrossRefGoogle Scholar
Lock, AL & Garnsworthy, PC 2003 Seasonal variation in milk conjugated linoleic acid and Delta(9)-desaturase activity in dairy cows. Livestock Production Science 79 4759CrossRefGoogle Scholar
Long, RJ, Apori, SO, Castro, FB & Ørskov, ER 1999 Feed value of native forages of the Tibetan Plateau of China. Animal Feed Science and Technology 80 101113Google Scholar
Long, RJ, Ding, LM, Shang, ZH & Guo, XS 2008 The yak grazing system on the Qinghai-Tibetan plateau and its status. Rangeland Journal 30 241246Google Scholar
Mel'uchová, B, Blaško, J, Kubinec, R, Górová, R, Dubravská, J, Margetin, M & Soják, L 2008 Seasonal variations in fatty acid composition of pasture forage plants and CLA content in ewe milk fat. Small Ruminant Research 78 5665Google Scholar
Neitz, MH & Robertson, NH 1991 Composition of Milk and Factors that Influence it. Bulletin 421. Pretoria, South Africa: Directorate of Agricultural Information, Department of AgricultureGoogle Scholar
Parodi, PW 1997 Milk fat components as potential anticarcinogenic agents. Journal of Nutrition 10551060Google Scholar
Peng, YS, Brown, MA, Wu, JP, Wei, LX, Wu, JL & Sanbei, DZ 2008 Fatty acid profile in milk fat from Qinghai plateau yak at different altitudes and parities. Professional Animal Scientist 24 479487Google Scholar
Sinclair, AJ, Attar-Bashi, NM & Li, D 2002 What is the role of α-linolenic acid for mammals? Lipids 37 11131123CrossRefGoogle ScholarPubMed
Stanton, C, Lawless, F, Kjellmer, G, Harrington, D, Devery, R, Connolly, JF & Murphy, J 1997 Dietary influences on bovine milk cis-9, trans-11-conjugated linoleic acid content. Journal of Food Science 62 10831086CrossRefGoogle Scholar
Timmen, H & Patton, S 1988 Milk fat globules: fatty acid composition, size and in vivo regulation of fat liquidity. Lipids 23 685689Google Scholar
Wright, T, McBride, B & Holub, B 1998 Docosahexaenoic acid enriched milk. World Review of Nutrition and Diet 83 160165Google Scholar