Effect of clover species in grass-clover silages and concentrate supplementation on milk fatty acid composition

Summary

The effect of clover species and level of concentrate supplementation on milk fatty acid (FA) composition has been studied. White (WC) and red clover (RC) grown in mixture with grasses were preserved in round bales and fed to autumn calving dairy cows during the first 10 weeks of lactation. Milk FA was higher in linolenic acid, vaccenic acid and rumenic acid for RC than for WC silage (0.90 vs. 0.79 %, 1.52 vs. 1.36 %, 0.90 vs. 0.75 % for these 3 FA, re-spectively), and RC silage gave a higher n-3/n-6 milk FA ratio than WC (0.98 vs. 0.72). Concentrate sup-plementation decreased the level of vaccenic acid (1.21 vs. 1.68 %), linolenic acid (0.63 vs. 1.05 %) and the n-3/n-6 ratio (0.55 vs. 1.16) as compared with no supplementation, and the effect of supple-mentation was similar for the two silages.