Tackling the future challenges of Organic Animal Husbandry - vTI

RAHMANN G & GODINHO D (Ed.) (2012): Tackling the Future Challenges of Organic Animal Husbandry.
Proceedings of the 2 nd OAHC, Hamburg/Trenthorst, Germany, Sep 12-14, 2012
both originate from dietary ALN and LA of which linseed oil supplies 54 % and 16 % respectively
(Glasser et al 2008). The response in ALA was disappointing (+39 %) but background levels were
high, exceeding 8.3 g/kg FA in summer UK organic milk reported by Butler et al., (2011), and 0.6
kg oil is a moderate feed rate. Later unpublished work shows greater increases in ALA from higher
rates. This work shows linseed supplementation of silage based diets for organic cows can lead to
fat quality comparable with summer milk; reducing saturated fats and increasing concentrations of
beneficial fatty acids.
Figure 1 Concentrations of beneficial fatty acids compared with typical levels in summer
milk (Butler et al., 2011) (linseed fed on days between arrows)
Fatty4acid4concentrations44g/kg4total4fatty4acids
27
21
15
9
VA ALA CLA9
summer4VA summer4ALA summer4CLA9
3
13'Jan 19'Jan 25'Jan 31'Jan 06'Feb 12'Feb 18'Feb 24'Feb
Suggestions to tackle the future challenges of organic animal husbandry
There is plenty of evidence organic milk supplies higher levels of beneficial fatty acids than conventional
milk but it can also be higher in saturated fats, especially in winter. This work clearly
shows linseed supplementation of winter silage based diets for organic dairy cows can produce fat
comparable with summer milk; reducing saturated fatty acids and further increasing concentrations
of beneficial fatty acids.
References
Akraim, F., M. Nicot, P. Juaneda, and F. Enjalbert. 2007. Conjugated linolenic acid (CLnA), conjugated
linoleic acid (CLA) and other biohydrogenation intermediates in plasma and milk fat of cows fed raw or
extruded linseed. Animal 1:835-843.
Butler, G., Nielsen, J. H., Slots, T., Seal, C., Eyre, M. D., Sanderson, R. & Leifert, C. 2008. Fatty acid and
fat-soluble antioxidant concentrations in milk from high- and low-input conventional and organic systems:
seasonal variation. Journal of the Science of Food and Agriculture, 88, 1431-1441.
Butler, G., Stergiadis, S., Seal, C., Eyre, M. & Leifert, C. 2011. Fat composition of organic and conventional
retail milk in northeast England. Journal of Dairy Science, 94, 24-36.
Chilliard, Y., Glasser, F., Ferlay, A., Bernard, L., Rouel, J. & Doreau, M. 2007. Diet, rumen biohydrogenation
and nutritional quality of cow and goat milk fat. European Journal of Lipid Science and Technology,
109, 828-855.
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