Milk fatty acid profiles

Synthesis of fatty acids via the malonyl CoA pathway does not proceed beyond palmitic acid (C16 0) and mammary tissue contains an enzyme, thioacylase, capable of releasing the acyl fatty acid from the carrier protein at any stage between C4 and C16. Probable interspecies differences in the activity of thioacylase may account for some of the interspecies differences in milk fatty acid profiles. 

Ward, A.T., Wittenberg, K.M., and Przybylski, R. 2002. Bovine milk fatty acid profiles produced by feeding diets containing solin, flax and canola. J. Dairy Sci. 85, 1191-1196. 

Hermansen, J.E. (1995) Prediction of milk fatty acid profile in dairy cows fed dietary fat differing in fatty acid composition. J. Dairy Sci., 78, 872-879. 

Feeding for Specific Milk Fatty Acid Profiles... 

The earliest efforts to modify the composition of milk fat used an insoluble formaldehyde-crosslinked protein to encapsulate unsaturated vegetable oils. In numerous studies using this approach, linoleic acid was increased to as high as 35%, w/w, of the total milk fatty acids (reviewed by McDonald and Scott, 1977). Bitman et al. (1973) fed increasing amounts of safflower oil encapsulated in formaldehyde-treated casein. The content of milk fat increased linearly from 3.5 to 4.6% as supplemental protected oil was increased from 0 to 1320 g/day per cow. The concentration of linoleic acid increased to 33% of total milk fatty acids, with a compensating decrease in Ci6 o and a smaller decrease in Ci4 0. The concentration of milk fat decreased to lower than pretreatment levels when the supplement was removed, a common observation (Pan et al., 1972). A typical milk fatty acid profile from cows fed a protected sunflower/soybean (70/30) supplement is shown in Table 2.1. 

Loor, J.J., Herbein, J.H. 2001. Alterations in blood plasma and milk fatty acid profiles of lactating Holstein cows in response to ruminal infusion of a conjugated linoleic acid mixture. Anim. Res. 50, 463 476. 

Hayashi, A.A., Medeiros, S.R., and Lanna, D.P.D. (2002) Effects of Conjugated Linoleic Acid (CLA) on Milk Fatty Acid Profiles and Activities of Lipogenic Enzymes in the Mammary Gland, Liver, and Adipose Tissue of Lactating Rats, J. Dairy Sci. 85 (Suppl. 1), 10 (Abstr.). 

Aurousseau et al. 2004 for a review see Scollan et al. 2006) or the effects of lipid-enriched diets (Mele et al. 2007 W sowska et al. 2006 Nod et al. 2007) on ruminal BH and consequently on meat and milk fatty acid profile. However, this extensive topic is out of the scope of the present chapter and will not be further treated. 

Tannins and Meat and Milk Fatty Acid Profile... 

Potkahski A, Szumacher-Strabel M, CieSlak A (2009) Effect of rapeseed and fish oil blend supplementation to dairy cows summer feeding on rumen parameters and milk fatty acid profile. Anim Sci Pap Rep 27 83-93... 

Gomez-Cortes, R, R Frutos, A.R. Manteeon, M. Juarez, M.A. De la Fuente and G. Hervas, 2008a. Addition of olive oil to dairy ewes diets effects on milk fatty acid profile and animal performance. J. Dairy Sci. 91, 3119-3127. 

Toral, P.G., G. Hervas, P. Gomez-Cortes, P. Frutos, M. Juarez and M.A. De la Fuente, 2010b. Milk fatty acid profile and dairy sheep performance in response to diet supplementation with sunflower oil plus incremental levels of marine algae. J. Dairy Sci. 93, 1655-1667. 

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