Effects of strain of Holstein-Friesian and concentrate supplementation on the fatty acid composition of milk fat of dairy cows grazing pasture in early lactation
WJ Wales, ES Kolver, AR Egan, JR Roche
Journal of Dairy Science | AMER DAIRY SCIENCE ASSOC-ADSA | Published : 2009
The effect of a grain-based concentrate supplement on fatty acid (FA) intake and concentration of milk FA in early lactation was investigated in grazing dairy cows that differed in their country of origin and in their estimated breeding value for milk yield. It was hypothesized that Holstein-Friesian cows of North American (NA) origin would produce milk lower in milk fat than those of New Zealand (NZ) origin, and that the difference would be associated with lower de novo synthesis of FA. In comparison, increasing the intake of concentrates should have the same effect on the FA composition of the milk from both strains. Fifty-four cows were randomly assigned in a factorial arrangement to trea..View full abstract
The authors acknowledge the technical assistance of Paula Thorne and the contributions of DairyNZ Lye dairy farm staff. This work was funded by New Zealand Dairy Farmers through DairyNZ (Hamilton, NZ) and the Victorian Department of Primary Industries.