Botanical composition of clover-grass silages affects milk yield in dairy cows

Røjen B.A. and Kristensen N.B.
Jaar van uitgifte: 
2015-06-12 22:15:00

The botanical composition of clover-grass silage is said to affect nutritive value and nutrient degradation kinetics. But does the production response of the cow reflect the standard chemical analysis which underlies the determination of feed value, and the morphological differences between grasses and clover? This study aims to investigate the effect of clover-grass silages differing in botanical composition on feed intake and milk yield. A 4×4 Latin square was carried out with first-cut 2013 silages under controlled conditions. Silage based on perennial ryegrass with white clover gave the highest intake and energycorrected milk (ECM) yield together with a tall fescue-based silage. The latter was surprising, given the general lower organic matter digestibility of tall fescue. Silage based on perennial and hybrid ryegrass with red and white clover produced the lowest intake and ECM. Unexpectedly, the measured variable which correlated best with the results was the content of red clover in the silages: intake and ECM decreased linearly with increasing content of red clover. This may, however, be confounded with effects of grass varieties among treatments. Results indicate that intake and production response may not be described solely by a standard chemical analysis of the silage, and that botanical effects have an effect on the cows.

feed efficiency, forage, clover-grass mixtures, red clover