title: Characterization of milk fatty acids based on genetic and herd parameters.
abstract: The objective of this study was to characterize the fatty acids (FA) in milk based             on genetic and herd parameters to investigate the origin of the different FA in milk.             Milk samples of 1912 Dutch Holstein-Friesian cows were analysed for 39 different FA             including odd and branched-chain fatty acids. The proportion of variation caused by             genetic and herd effects was calculated. In addition, genetic and herd correlations             among the fatty acids were estimated and a clustering technique was used to visualise             these correlations. The results indicated that in Dutch milk C12:0 is not completely             synthesised de novo but also partly blood derived. It was suggested that C20:0 in milk             is formed from the action of elongase enzymes on C18:0 and that the odd-chain FA             C5:0-C13:0 and a part of C15:0 and C17:0 are synthesised de novo while the             other part of C15:0 and C17:0 is blood derived. Furthermore, this work gives an overview             of the opportunities to change the concentration of individual FA both by breeding and             feeding. It is clearly shown that the extent to which the individual FA can be changed             varies greatly and is dependent on the origin of the different FA in milk.
authors: Dairy Science and Technology group, Wageningen University, PO Box 8129,                     6700 EV Wageningen, The Netherlands.
authors: Jeroen M L
authors: JM
authors: Heck
authors: Hein J F
authors: HJ
authors: van Valenberg
authors: Heim J F
authors: HJ
authors: van Valenberg
authors: Henk
authors: H
authors: Bovenhuis
authors: Jan
authors: J
authors: Dijkstra
authors: Toon C M
authors: TC
authors: van Hooijdonk
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics* / Q000502:physiology*; D016000:Cluster Analysis; D005227:Fatty Acids / Q000737:chemistry* / Q000378:metabolism; D005260:Female; D008892:Milk / Q000737:chemistry* / Q000502:physiology*
chemical_list: D005227:Fatty Acids